I have waded through all of the amateur videos, the informed videos and the well informed videos and I have gleaned a little knowledge from them all. Some, more than others ( like testing + and - wires at both ends before frying a new £200 battery) . But now I feel I have arrived at Ebike University. Greatest Ebike channel of them all IMO. Thank you from Ireland and keep up educating the masses.
The Ebike community seems to love the “I could climb a hill” selling point, but I’m over here in Florida getting reminded every couple videos that hills exist. Cheers.
Excellent tutorial. I had to read and study lots of detailed books about this subject to understand the differences and how they related to each other. In less than 11 minutes, you've perfectly, clearly and concisely described and explained what I had to learn the long and hard way. I wish this video had been around when I was learning this stuff.... well done!
Great video... Yes, torque ratio to watts is the most important measure. It's how the bike will perform off the line and up hills. Basically how the bike will 'feel' to the rider. - Sluggish vs muscle.
last but not least wheel diameter (in case of hub motors which put less strain/wear on the mechanical drive train) plays into how efficiently those Newton meters actually propell the vehicle forward. The smaller the wheel the sooner rotation and efficient rpm can be achieved. I have a rickshaw which often amounts to a total system weight of 600+kg, but with a geared hub motor in my 16 inch front wheel I'm getting the most when starting the race at the green light at Octoberfest outrunning my colleagues with 200kg less who are running the same 250W nominal system on slimmer tires but with 26 inch diameter. (it might also have to do with me being the GOAT in rickshaw racing but don't tell them that ; )
Well, for those like me, haha, I was unable after welding batteries purchasing BMS's to be able to understand exactly how that final S series was counted. It finally hit me after going back to basics, watching these very easy to follow builds. That, the final S count that I was always missing was: the very first battery that has both the positive and negative going to it, even though it wasn't exactly making an S series connection, was the very last counted Series battery. Maybe very easy for everyone else, but had been banging my head around that for months. So, Thank you so very much for helping me stop feeling so stupid and knowing for sure I knew how to correctly look for and buy the correct BMS for the battery builds I was doing.
That's not correct. In a series connected set, positive is on one end, negative is on the other. the path of electricity has to travel through each battery one after another.
In UK (and EU) the max continuous power output is 250W for an electrically assisted bicycle but if you want a higher output bike then that is classed as an electrical moped i.e. a motorbike driven by a motor and pedals. The issue with this comes from the requirement that to be an electrical moped it needs to be type approved or to have an 'Individual Vehicle Approval' to show that it complies with UK/EU vehicle build laws and that it will also need to be licenced, taxed and insured for a minimum third party cover. The rider must also wear an approved i.e. motorcycle crash helmet and preferably protective clothing and although not mandatory, the police might pull you over for inappropriate wear if you had classic Lycra shorts and top on.
Thanks, here in the UK, as you say we have 250w continuous, I am very happy for the manufacturers to allow us to overamp their motors for more power, they know we will not burn them out at say 750 watts for a reasonable time. I may be wrong, but I think the Bafang 250, and 350 are the same motor but different controllers to allow more power. It is a way of giving us a good product and stay within regs, a point you made well.
only danger with overamping would be being involved in an accident having your bike looked at by a sworn expert making you liable for operating an illegal motor vehicle. The bike squads in Germany are no fools and are regularly making examples of obviously overpowered "250W"ebikes (which could be legal if they had a moped plate and all the other items required for fast ebikes)
@@velotillthis is why the laws are a bit dumb. What should really happen is there should be a law on use of peak power to allow fast starts and uphill runs tied to the amount of torque provided by the rider. Fast starts for 10 seconds up to 10 kmph on flats (until you pedal past it) and during cornering to get you out of trouble and when hitting an incline allowing the peak power to stay on for as long as you provide enough torque to keep up to the maximum speed llmit of 25 kmph.
1:27 Yep, a big 10 ton trolleybus has an electric motor rated at 100kW. That low! But that is the continuous power. And trust me, during acceleration from standstill, the motor drives much more current than 175A (runs at 600V). That is the reason why there are components limiting maximum current, as the motor would happily take all it can get. And yet, differentials and axle reductions wear out sooner on trolleybuses than on buses. And if the regulator malfunctions, a trolleybus can easily do a burn-out on a dry paved street. Of course, do it three dimes and you can replace the whole axle, if the CV joints on the shaft between the motor and differential do not break sooner. Or you blow the circuit breaker in the trolleybus (should break around 380A, but that is only theoretical) or you trip the breaker in the electrical substation feeding the section where you draw your power from. If you had no protection circuits and a very powerful source, applying 600V directly into the motor would most likely result in lightnings flying out of it and ripping it from the frame of the trolleybus, destroying everything between it and the wheels of the driven axle(s).
WOW, Thanks a lot! As a retired electrician, Your explanation clicked 100%. Something else I see is batteries being rated in watts with no reference to amp hours. Often digging for other sources, I find the '360 watt' battery is 48V and doing the math get 7.5AH which is kinda small... Just liked/subscribed and bookmarking this video!
im unsure tbh 360 watt would refer to the motor power the battery should be rated in AH however what I think might be going on here is for reasons I don't know they could be rating the battery in watts referring to the motor its suitable for for example calling a 32 volt battery a 250-320w battery because that's what you mostly use for those and calling a 42v battery a 500-700 watt battery with a 72v battery being a 1000+ watt battery for reference my bike is specced as follows 350w motor 32v battery 11.5ah battery if we wanna rate my battery in W/h as opposed to A/h my battery is 368W/h in capacity but generally when it comes to ebikes if its talking amps there referring to the AH of the battery if there talking watts its almost always the rating for the motor and volts being what the battery is delivering there's a whole thing for over voting the motors to get a lil extra performance as well as going for higher voltage batterys to reduce charge times as all chargers are limited by there amp ratings so upping the voltage is a easy way to get more watt hours into the battery faster without pushing more amps I've even seen some ellect to install 72v batteries and regulate them down to 32 to benefit from having a smaller battery and faster charge times but still having the range a larger lower volt battery gives them
@@Sarge92 That's a lot to wrap one's head around... I note that 'A' also refers to controller ratings. We could really confuse things saying my T42 is only 1.1 KVA peak... If a controller is rated up to 72V and being used on a 48V hub, what's the risk of going in series with a 12V agm with the 48V li-ion to get 60V operating voltage?
The battery rating in Wh is more honest than giving A*h, as the Wh charge actually defines the amount of energy stored in the battery. A good comparison factor is the battery consumption in Wh/km or Wh/mi. Giving only Ah rating (without the voltage) is deceitful. Giving Wh is honest. Big brands always give the battery rating in Wh as not to deceive the customer.
@@StefanMikulski You say "Giving only Ah rating (without the voltage) is deceitful".... I submit, So is Wh - (without the voltage). 360WH could be 36V 10AH or 48V 7.5AH... Speed comes from voltage. VA's or Watts is actually 'power' giving an idea of how long a load will run. Or, in the case of a motor, it's hp rating since 742W=1hp.
@@johnw65 speed comes from voltage? How comes my 36V Specialized Turbo Vado 6.0 can get at 45 km/h (28 mph) while a derestricted 48 V Specialized Turbo Vado SL can only get at 34 km/h (21 mph)? No, the voltage is irrelevant here. Speed comes from the motor power, which is mechanical 520 W peak in the former and mechanical 240 W in the latter. The speed also affects the battery energy draw. That's why the former battery is 604 Wh (36 V 16.7 Ah) and the latter is 320 Wh (48V 6.6 Ah).
I know most are watching this for the knowledge of the ratings, but this has actually taught me a lot about battery building. A concept I never understood was the max wattage rating, and now I understand, its just the max current the battery will put out multiplied by voltage.
You should run a non profit association that lays out a spread sheet of the bikes and all their true non biased ratings. …you know the truth about these bikes. Well done video!
You forgot to mention that a particular motor designed to go with a specific voltage will not put out more power just by changing the controller, the voltage will have to go up, which means changing the battery as well as the controller. Ohm's law hasn't changed!
That’s totally wrong. Not only have I swapped out batteries from 48V to 52V, I’ve swapped controllers after switching to 52 and my CLyte 3540 (rated at 1000W) and upping my controller from 26A continuous to 35 continuous definitely puts out more power. There are literally thousands of examples of this to choose from, not just my experience of riding my DIY ebike 30,000 miles. Yes, it is more susceptible to heat (loss), but it’s certainly not all lost to heat. I assume you don’t have an ebike. Ebikes.ca has a simple motor calculator and you can input values for many types of motor and controller combinations and see the data yourself.
What you call power is the torque which is a function of electric current not voltage. Varying the voltage would vary the speed. Amps = Torque (more powerful), volts = speed (faster)
During my studies for electrical engineering the lecturers told me that the advertised motor power is usually mechanical. the mechanical power is calculated by multiplying angular velocity and torque. Mechanical power is the power you get from motor. The power you were talking about was electrical or the input power.
I love how continuous and peak power has an excellent explanation to them, telling you exactly what they're about, then you get to nominal power and it's basically 'this means nothing. it could be true, it could be false, and even if it is true you won't know "how true" the rating is unless you test it.' It is pretty hilarious and i can see where the frustration can stem from that.
Very good explanation of "power". Keeping it simple using VA can help those not familiar with end to end input to output and the various losses along the way. Something to consider is the fully charged battery versus the nearly discharged battery. Power is greatest when the battery is fully charged and is minimal with a mostly discharged battery.
Sooo.. My Super73 SG1 (EU version of the S1), has a nominal rating of 250W, which is the maximum allowed wattage in Europe. The motor also says 250W etc. However, having a 48V battery, and the controller's current is rated at 10A with a maximum current of 20A, it's very obvious that this is a 500W motor with a peak at almost 1000W, which is the same as the original American S1. The European version is electronically limited though, but I've unlocked it by plugging the US throttle in, and I'll just say that if this is "250W", then it's the most powerful 250W motor in existence 🤣 Ain't complaining though!
This is my first time to one of your videos. I’m subscribed!! I understood everything while you talked, but need to listen a couple more times to really understand. I’m shopping for my first ebike. It isn’t easy. But, you have helped a lot!! Thank you! I’m going back to listen to your other videos! I needed a white board with your numbers on it. Visual learner, here. Good job!
this channel is quickly becoming one of my favorite youtube channels, this video is extremely informative, i dont yet have an ebike but my father and i are both interested in getting an ebike so we have been trying to soak up as much info as we can before purchasing our first ebikes, thanks for the all the informative videos you put out there :)
@@acehighdan sorry to hear that. Hopefully parts will become cheaper in coming months. One price of advice I would give for those just starting out is that if you pick up a Liitokala hoverboard battery from AliExpress for $25 you have got a sufficient battery to get you started with a 36v kit. If you could do a shift extra each week at work, you may be able to save up the $150 needed for the motor and controller in a short time Or wash cars or Windows for money. Or now lawns
Love your channel. Awesone explanations. So look at these stats and tell me if Im right... Motor rated 750 watts. Peak 1000 watts. Battery 48V 20AH (960 WH) lithium battery Controller 48V, 25 ± 1A; 12MOS Am I correct to assume that the controller at 25 plus or minus makes up the difference between continuous and "peak" with the +5 amps beimg pumped into the motor to produce the extra peak 250 watts which ultimately overheats (at duration). If I'm correct, I see why manufacturers are tweeking out another 5 amp controller over 20 amp battery in those (required) situations. Also, ambiemt temperature plays a crucial role.
This is my random comment, The Ultimate Do It Yourself Ebike Guide. Thank you for this video, it explained a few things I was trying to figure out. 500W 32kmh/20mph limit where I live.
Yes & Motors have torque & power curve. A hub motor may find life hard turning slowly on a steep hill & heat up fast, but a mid drive is geared crank speed, so should be in the middle of its design range hill or flat. & its also important to remember the gearing factor difference between Torque for a hub motor & a geared mid drive.
Thanks for your clear explanation of ebike power. I’ve been researching the subject for a couple of weeks, and yours is the best, most straight forward explanation yet. Again, thanks. Please keep up the good work.
First class and full marks - easily one of the best explanatories I've ever seen. Thank you very much and happy travels (remember: "No helmet? NO WAY!").
I have a question About DC power cable? 36v up to 72v, 70ah Must put a fuse on there With a controller from 3000w up to 6000w How can I calculate which fuse should or not Or does the controller do that, protection of + power cable Think this is important Thanks You make good videos and very educational
Thanks for explaining some of these terms as they apply to the ebike market place. I just recieved my T-1 replacement and didn't understand why the new motor was labeled 250w. Now I do.
The basic direct drive hub motors like violamart have the same direct drive hub motor but the controller varies, it could be sold as 500W, 750W, 1000W, 1500W or 2000W with only the controller varying and the hub motor remaining the same. How is that motor rated. Also if you buy lets say a 1000W version and use it with the minimum size battery it will accept about 48V at 12Ah in the road legal mode it is 250W approx (more like 300W) but if you disconnect the wire you get a 50% boost to 450W approx but the battery can peak at about 960W (20A) output for about 60-90 seconds or about 700W in road legal mode. It's confusing as clearly the battery BMS and controller and motor are not at the same level. I guess the BMS dictates the actual power the motor can receive, the controller could handle more and the motor itself could handle much more. I'm not sure what the nominal or continous rating of such a hub motor is but I guess at least 1000W. I've heard of Bosch motors easily peaking over 700W despite being road legal but many would view the Bosch as road legal and the home kits as not and its one factor why people pay more for a Bosch bike as they worry about the legal implications of a crash with a kit motor hub. The law seems a mess. However here in the UK I don't think anyone has been prosecuted with a home kit and you wonder if the police just check that it doesn't assist beyond 15.5mph because its the only simple test they can do.
I have the 1000 watt voilamart hub motor, and it peaks around 1200 watts according to the screen. I bought the voilamart 1500 watt controller instead of trying to play with the internal shunts on the stock controller. It has been sitting on my work bench for over a month now, cause I wasn't sure if the hub motor would take it or not (wire size)... I wish Micah would respond to comments... I think I should be ok as long as I don't full throttle it, I just want some extra torque on take off
@@chrisnmichelle0218 Can I ask what battery you are using both volts and amp hours plus if you know what peak current it can deliver for how long? Which cells are you using if you configured the battery yourself? I have the yosepower 48V 12.5Ah hailong case battery pack which uses Samsung 2500mAh cells which allows a peak current of 20A for 60-90 seconds. As stated above pretty much the minimum the 48V 1000W motor will accept which I think is stated as 48V 11.5Ah minimum battery. I use it in the restricted street legal mode partly due to legality but also because the battery is such a low capacity for this motor.
@@bonzobanana1 16s 1p 48v 20ah lifepo4 BTR power battery (www.ebay.com/itm/282691708617) it is made with lifepo4 pouches, not cells. 50A continuous discharge, 100A max discharge. The battery is great, but it weighs almost 20 lbs and I have to mount it on a rack behind the seat which throws the weight balance off. I have been buying 32700 liitokala lifepo4 (m.aliexpress.com/item/4000073953939.html?pid=808_0000_0109&spm=a2g0n.search-amp.list.4000073953939&aff_trace_key=0f27108c4dae4f51866478090c8a265e-1598364242794-04812-UneMJZVf&aff_platform=msite&m_page_id=6236amp-8afh0fKpUqPr1GppmYPgnw1598364304447&browser_id=3d094fe9d33b4a2fba89779d51150c11&is_c=N) 3.2v 7ah batteries, with continuous discharge rating of 35A per cell. I plan on building a 16s 3p battery with the 32700 batteries, and a 50 amp bms for it. That would get me 51.2v 21ah battery with a continuous output of 50 amps limited by the bms, I plan on using a bms made by Daly, as they have great ratings. I'm kinda sold on lifepo4 batteries because they have a much longer lifespan of 3000 charges (I don't ever drain my batteries dry) and just being a safer and more stable composition where I don't have to worry about thermal runaway if I push the batteries really hard.
Hey, just a heads up. Several of your links to Aliexpress are dead. The 18650 cells link goes to a charger. The 1000 watt complete kit is dead. There are others that are dead, just some housecleaning to do with your links. Thanks for the videos! I'm a fan.
Wouldn't torque increase as you increase the operating voltage though? So the torque rating would only be applicable for the listed controller / battery. If I throw a 52v battery in a 48v controller, the torque produced would increase
The power rating system reminds me of the Japanese gentleman agreement between the Toyota supra and Nissan GTR when it comes to horsepower making in the same
Hi sir, I still new and planning to buy an escooter. Found a escooter with two different model. Which one is you think much better? A. 48v 10ah with 500watts B. 48v 13ah with 1000watts
You talked about this several years ago (I think too, it’s also in your book) good to hear again. I think you put it better here. It’s not as text book more layman’s terms I guess. Same but more relaxed and I think easier to understand. Good to hear again very important. And yes we do benefit if we know how to take advantage. That we can (w/aftermarket controllers) put together a bike that we love to take for a ride!
you can easy put 350watt on a 250watt motor as long as your rides aren't very long(time depending on ambient outdoor temp) my home work rides take max 20 min, about 6km(aprox 4miles)
Very well explained, thank you Sir. Question/s how/where do find the controller max output? where do you find the motor's true continuous output? Could you find out from the components cereal number?
Great info..... What about matching Batteries with controllers regarding Amperage? The battery continuous Amperage should always be higher than controller continuous Amperage rating?
I just ordered a Ristretto 512. Battery is 52v 30Ah. Motor: street legal 750w and race mode 4500w peak, which is claimed to be 40-45mph. 52v x 30Ah = 1560V. Does that mean that this motor can run at 1560V continuously without overheating? Therefore I would not be able to ride the bike at 40-45mph without the motor overheating?
ADO are interesting on this front. The ADO Air 20 has a 250W battery and 350W on the international version. However, both are apparently marked as 250W on the motor. It lists as 9.6 amp hours (36V battery). Which means it is basically closer to 350 watts peak on the international version while artifically limited via the controller on the EU version and does not include the thumb throttle. Their Beast ebike has a 250W motor listed ONLY but is 14.5 amp hours (36V), which means it peaks at around 522 watts. Lots of shennanigans going on with many of the manufacturers especially people like Engwe ;)
Also, a couple other things: European "continuous rated power" isn't continuous power! It is, to quote Regulation EU No 168/2013 Article 3(35): "‘maximum continuous rated power’ means the maximum thirty minutes power at the output shaft of an electric engine as set out in UNECE regulation No 85" And "maximum thirty minutes power" from that UNECE regulation: ""Maximum 30 minutes power" means the maximum net power of an electric drive train at DC voltage as defined in paragraph 5.3.1. of this Regulation, which a drive train can deliver over a period of 30 minutes as an average" Additionally, there's test procedures in that regulation that define it better, and where the loophole comes in - the power level must be the manufacturer's best estimate of maximum 30 minutes power, and the RPM must be in a speed range that allows greater than 90% of maximum peak power (which is determined in a separate test). If the manufacturer estimates too high, of course, it'll fail the test and they'll have to re-run it, but if they estimate too low, it'll pass. The US regulations not actually saying what power rating standard is in use make me think the safest bet is to assume the more (but not the most) restrictive interpretation - 750 W peak output power. I don't think any of the vehicle regulations in the US are actually using continuous power (whether over a specific time or indefinitely), but then the US doesn't usually restrict power output, either, outside of e-bikes and state laws restricting what can be used as a moped/motorized bicycle/scooter without a motorcycle license. Then, there's one problem with your methodology of determining peak power: efficiency. So, just because you've got 36 V, 15 A coming from your battery doesn't mean you have 540 W coming out of your motor. If your motor/inverter system is 85% efficient at peak power, you've got 459 W coming out of the motor (and 81 watts of heat that your controller and your motor need to dissipate), and that's your real peak power. (There's additional drivetrain efficiency considerations downstream if you have a mid-drive, but my understanding is that power regulations care about motor output, not wheel output.)
US goes for Continuous power. Rating the motor by peak, is incorrect for it's performance. Peak is the RPM and torque a motor goes through before it reaches it's end power point, then tapers down in power. So once it's up to speed, it's not at it's peak power anymore. Same as Gas cars,etc. If they ruled for Peak, Electric/Gas devices would suck. It's like saying, This car can only have 500rpm and such % of torque. You realize how SLOW that car would be to get up to speed? It'd be like a snail trying to get up to 40mph, in 20mins. So if a state has a rule of power of a 750watt motor as limited. That is continuous power rule. Not Peak. The motor can have 2x more Peak, because that start power the motor goes through. Again like a gas car,etc. It's the start of the motors run to get whatever it's pulling/pushing up. Then it lowers down to it's continuous power performance which runs at a stable set.
@@TheAvkdutch You're a great example of how dumb the world is. "Will listen to this stupid twit on this epic website that doesn't know crap, But not to someone who knows the truth on a comment." You should've just never commented, Cause you just made yourself look like a fool and just showed everyone else like you how dumb they now can see themselves.
Auto manufacturers underrate their motors too. The 06 Chevy cobalt SS LJS supercharged 2.0l motor is advertised as producing 215 crank hp. I assume this if to keep insurance rates low, because they routinely dyno at 235hp at the wheels before any mods. I'm happy to get an underrated motor in my e-bike because excellent reviewers, such as yourself, make head to head comparisons revealing the "truth in advertising" very quickly.
I have a 500 watt 3 speed 90 pound throttle controlled ebike and a 52 pound 350 watt pedalec fatbike. Both seem to produce about the same power. The fatbike specs say 700 watt peak and goes from 0-30kph in about 7 seconds. Considering the weight of the fatbike tires, it seems to be a stronger motor and the taller gears allow me to reach road bike speeds of around 40 kph under ideal conditions. Had expected the 350 watt to be slower but it is comparable to the 500 watt ebike. The plus side is that I can use the 2 frame mounted fatbike batteries on my 500 watt ebike with a 2 pin DIN plug plus 2 batteries on the 500 watt ebike. This allows me to use 40 pounds of battery on the bike which I expect will give me somewhere around 100 miles range with pedal assist. I have 2 batteries mounted on the frame bags and 2 fatbike batteries in panniers. should provide decent battery range when towing my tent trailer too.
1:38 Wouldnt power be either controller voltage * phase amps OR battery voltage * battery amps? Phase and battery current would only really converge when the controller is at 100% duty cycle at high RPMs where you're back EMF limited At lower speeds youd be limited by either the phase or battery current limits so by definition the voltage at the motor would have to be less than the battery voltage, if we whacked the motor with full battery voltage at 0 RPM, current draw would approach infinity (well it would approach the short circuit current of all the wiring) and fry the controller.
Excellent information, I’ve been using the torque number and 750 W as my comparison point since my neighborhood is hilly. My driveway has 7+ feet rise of elevation 😂
Hi Micah, you have a great chanel, Im looking at building a water jet surfboard using a 300A ESC with a 9000w motor, Im looking at making 24v battery, with 7 cells in series and 8 cells in parallel. Im looking at using 56, 21700 SAMSUNG 40T, 4000mah with a Maximum Continuous Discharge of 30A per cell, I'm hopefully aiming on not pulling no more than 150A, from the pack, would you use say a 200A BMS or would you split the cells into 4 packs and use 4 x 50A BMS's
great info, question I have folding Tesgo ebike and display does not show actual volts can I wire to the backside of battery wire going to controller and out to a voltmeter to see actual volts? My controller is in the frame, and I can take off the matting side and get to the positive and neg cables. I could drill small hole and run wires up to my handle bars.
This is a very helpful video, Thank you! Question, I have a Heybike 500w (48v 12.5 amp battery) Heybike states that my Mars Ebike has a peak power of 1000w and yet when calculating the figures I get 720 watts (a 15 amp controller x 48v=720w) not 1000w? How is this possible? Is Heybike overstating their specs.? The stated torgue rating is 50-60Nm.
Nice informative presentation. A couple comments. 1) Does anyone know if the motor manufactures are specifying a maximum continuous stall torque, something else? 2) In shopping for a ebike, I calculated the miles and elevation I would typically be doing here in Portland Oregon. It came out to 70 miles a week and 4,000' vertical feet. The dealers that addressed that issue were unanimous is saying"you need the biggest motor and battery you can afford", and then advised it will probably come up short on my hilliest days.
Is there a torque rating/watt power chart somewhere? That would be great to know. Also, some guys on the endless sphere forum were telling me that motors have a volt rating of their own. Is this true? Cause I though the voltage was relative to the battery pack you hook it up to? I certainly can never find one when I'm buying or labeled on any of my motors.
Good info, been messing with ebike for a while and came to these ame conclusions. However I have also read that torque numbers can be fudged and interpreted differently so also not a reliable number to focus on. Best bet is to look at all the numbers together and also look through forums etc to see what people are saying about a particular motor you are interested in. Mid drive is tempting me but for reliability I just convertedmy mountain bike with full suspension to 1kw hub drive and it's a nice powerful fast ride.
Super informative, learned bunches. Is it possible to run a controller with a S866 LCD set at 48 volts with a battery that is 36v? Or would having the system set to 24v with a 36 volt battery work at all or make the bike go faster. I have a Bolt Pro with a aftermarket 24/36/48/60 controller and seems like I'm stuck at approx 20mph. And that's with the learning loop disconnected which I was told would free me from those 20mph bonds. I'd appreciate your opinion on what I should do next. Thx in advance, Dan
Imo it really depends where you live, if it's flat-land almost any ebike can push you but if hilly that's a totally different context, I have a bike with a Bafang Ultra that when you give -it the gas draws 4 to 7 times the energy that a typical European bike does, even a big battery pack can't give much range at that rate...
Hi Micah, would you agree then that a 500 watt motor in the rear wheel with (usually) 7 gears is going to perform the same as a 500 watt mid drive motor also with 7 gears & all other things being equal as well? There seems to be this belief that mid drives perform better than rear hub motors but I believe that is only true if you are comparing a Mid Drive to a Direct Drive Motor without the same gearing. Your opinion please.
Great video very informative. I will be looking into this further.So i should be looking for continuous power.1200 watt motor ,with a 15 amp controller equals 18,000 or1200 times 48 battery volts equals 57,600 . What am i really needing to know here? I ran my battery down with an incident i had with a flat tire an i would like to no why that happened also?
Your calculations are way off. A 48V battery at fully charged is 54.6V. Suppose somehow your 15A controller draw max current that would equal to 819 Watts, so if you have a motor capable of 1200 watts continuous it can never get the juice to run at 1200 Watts, unless you upgrade your controller to a 25A one.
I can't seem to find the answer to How can you determine/verify the exact rated watts of a controller?? If I buy a 1000 watt controller how can I be sure it is what is says it is. What electronic components dictate the watts of the controller? amps I can check with a ammeter. Watt output is amps x volts. That can vary regardless of the watts of the controller.
If you can physically gain access to the controller, it's printed on a sticker. It depends on where it's located and the difficulty in getting to it. To get to mine, all l had to do was remove 6 screws and the controller was right there, but protected from the elements. Hope that helps.
I hope you will answer my question Should the controller be equal in? Amp Matched on battery of, Quantity in amperes What is the correct ratio in amps On 2 motors from 3000w up to 6000w Can you help me with this I do not know ?
Good day to you as far i can understand on your explanation tha combination i have to run a motor hub is way not to good, i purchase a 48v 350 motor hub and using a 48v 500w controller and power it with 48v 13s 4p 16850 battery, please recommend the good combination with this voltage. Thank you
That is going to be my winter project, I have been ordering LiFePo4 32700 batteries, to make a 16s 3p battery pack. Probably will go with a Daly BMS. I'm also curious what welder you got, and what thickness of nickel you plan on using
Here are results of that tab welder. Now im not an expert on welding but maybe someone can answer my question on it. Again this is a first time thing for me and maybe I bought a bad welder but if anyone know's more about how good or bad I did id love to know. Thanks again! ua-cam.com/video/LERZ14QSksE/v-deo.html
It's have a bafang 750w motor and 48v 17ah battery setup. I was running it on a single speed drivetrain 44/14. I have been told it will damage the motor and is putting to much strain on it. Would this be the case?
Maybe you can help i have a Super73 RX and every time we do this huge bike ride all over NYC im getting range anxiety and everyone fights for the electrical outlet that's available. My question is can i put an additional aftermarket battery and will my bike recognized the BMS on it? thank you in advance
So over what period of time does the motor have to get max 250 watt according to EU regulations? And how do Bosch and others follow that when their max power is 600-800 watts? For how long will it stay on max power until it limits the power to comply with the regulations? Or do they just ignore the regulations and downrate the "nominal power" while the continues power in reality is much higher?
Hi Micah, just a little bit of clarity please on power. Isn't this based on what cells you have rather than the controller? For example an E-Bike with a pack 37V, 17Ah, gives 630W max. The controller might be rated to handle 750W but it would never receive that amount right?
So when i buy a battery and it reads 72v 33ah. The 33ah is the size of the controller it can handle. 72 x 33 = 2,376 . I have 2x 5000watt motors with two 50a controllers. I can use a 96v but that’s just to much power.
Does it matter if you run a motor at a higher voltage than intended though? Aside from cooling the total power I can't see any reason a simple electric motor would mind more voltage - within reason obviously. All the sensitive electronics are in the controller as far as I understand. In the extreme the engine parts might not tolerate the extra physical strain of more torque, but I doubt that 250w and 750w notors are much different in physical construction. I'd love the input of an experienced builder here. This is not advice - just a hypothetical based on my understanding of simple electric motors.
Pretty good. I find it helpful though to go to the next stage as what we are trying to do is compare the human power at the back wheel compared to the assistance power at the back wheel. And for that we need to talk about temperature and efficiency, as obviously not all motors and controllers are the same, plus of course efficiency is a map rather than a fixed number. If we know the efficiency at say 25C of the individual components and calculate the battery to wheel serial efficiency by multiplying each component by the next we end up with the actual power at the back wheel. Volts x Amps at battery x serial efficiency. If I had the spare cash it would be fun to use a powertap hub to see the combined rider and assist output at the wheel and a powertap or similar at the pedal crank to measure rider input. With a few simple sums we’d be able to genuinely determine the total and rear world power split. Enjoyed your battery book. Thanks.
I have been watching your videos for a long time and thanks for your information I learned a lot throughout time!!! I became scooter technician and a lot of information came of watching your videos!!! Thank you my brother as always! Great content!!!
why torque gets so much attention? you can anyway use a gearbox and increase your torque as much as you wish (unless you do with wheelhub motor) . I'd be more interested in efficiency of a motor in various working conditions
A good tutorial. However, there is one thing that has been slightly overlooked, which is the electrical vs. mechanical power. The 250 W continuous power is not the electrical power (V*A) but mechanical power, that is, (V*A) * mechanical efficiency. Contrary to what was said in this video, the mechanical efficiency would rather be up to 80% (not 90% as it was explained here). Let us take one of the few big brand motors with actually low power, which is Specialized SL 1.1 motor by Mahle, with torque of 35 Nm. The continuous power of that specific motor is equal to the peak power, and it is 240 W MECHANICAL power. It is possible to digitally measure the electrical peak power of that motor, which is 303 W. Meaning, the mechanical efficiency of that motor is 240/303 W = 0.792 (79.2%). Now, if a cheap motor manufacturer claims 750 W of continuous power, they probably mean the ELECTRICAL power. Hence, those cheap motors probably deliver far less of mechanical power than advertised.
I am new at E biking. I just now put a 118 miles on my bike. I'm still trying to figure out maintenance. Where do you get spare parts we bought cheap E bikes? Walmart specials $500 Hurley K.
May I ask, What would be a good size (Battery/Controller) for me (237 LBS) with 1000W befang front hub motor. Want max of 28 mph but will not be going that fast 99%.?
Question.. does enabling dual motors on a scooter uses less battery? Because if the front motor is off, it create drag so the back motor uses more power? Is this myth true? ty
It's a blessing this channel exists to give answers about these things. This guy just get straight to the point and explains everything in detail.
And i was waiting for someone to come and sit on left side of that couch lol
Lol
@G MONEY They are bots, I don't know why you are yelling at bots but ok.
Rule of thirds, baby.
@G MONEY BEEEAAAANNNNSSSS
@G MONEY BEEEAAANNNNNSSSSSS
I have waded through all of the amateur videos, the informed videos and the well informed videos and I have gleaned a little knowledge from them all. Some, more than others ( like testing + and - wires at both ends before frying a new £200 battery) . But now I feel I have arrived at Ebike University. Greatest Ebike channel of them all IMO. Thank you from Ireland and keep up educating the masses.
The Ebike community seems to love the “I could climb a hill” selling point, but I’m over here in Florida getting reminded every couple videos that hills exist. Cheers.
Excellent tutorial. I had to read and study lots of detailed books about this subject to understand the differences and how they related to each other.
In less than 11 minutes, you've perfectly, clearly and concisely described and explained what I had to learn the long and hard way.
I wish this video had been around when I was learning this stuff.... well done!
Great video... Yes, torque ratio to watts is the most important measure. It's how the bike will perform off the line and up hills. Basically how the bike will 'feel' to the rider. - Sluggish vs muscle.
last but not least wheel diameter (in case of hub motors which put less strain/wear on the mechanical drive train) plays into how efficiently those Newton meters actually propell the vehicle forward. The smaller the wheel the sooner rotation and efficient rpm can be achieved.
I have a rickshaw which often amounts to a total system weight of 600+kg, but with a geared hub motor in my 16 inch front wheel I'm getting the most when starting the race at the green light at Octoberfest outrunning my colleagues with 200kg less who are running the same 250W nominal system on slimmer tires but with 26 inch diameter.
(it might also have to do with me being the GOAT in rickshaw racing but don't tell them that ; )
Well, for those like me, haha, I was unable after welding batteries purchasing BMS's to be able to understand exactly how that final S series was counted. It finally hit me after going back to basics, watching these very easy to follow builds. That, the final S count that I was always missing was: the very first battery that has both the positive and negative going to it, even though it wasn't exactly making an S series connection, was the very last counted Series battery. Maybe very easy for everyone else, but had been banging my head around that for months. So, Thank you so very much for helping me stop feeling so stupid and knowing for sure I knew how to correctly look for and buy the correct BMS for the battery builds I was doing.
That's not correct. In a series connected set, positive is on one end, negative is on the other. the path of electricity has to travel through each battery one after another.
Can a maximum current ina. Battery be 32a&72v? Is that correct???
your channel has been immeasurably useful in getting into ebikes!
In UK (and EU) the max continuous power output is 250W for an electrically assisted bicycle but if you want a higher output bike then that is classed as an electrical moped i.e. a motorbike driven by a motor and pedals. The issue with this comes from the requirement that to be an electrical moped it needs to be type approved or to have an 'Individual Vehicle Approval' to show that it complies with UK/EU vehicle build laws and that it will also need to be licenced, taxed and insured for a minimum third party cover. The rider must also wear an approved i.e. motorcycle crash helmet and preferably protective clothing and although not mandatory, the police might pull you over for inappropriate wear if you had classic Lycra shorts and top on.
Thanks, here in the UK, as you say we have 250w continuous, I am very happy for the manufacturers to allow us to overamp their motors for more power, they know we will not burn them out at say 750 watts for a reasonable time.
I may be wrong, but I think the Bafang 250, and 350 are the same motor but different controllers to allow more power.
It is a way of giving us a good product and stay within regs, a point you made well.
only danger with overamping would be being involved in an accident having your bike looked at by a sworn expert making you liable for operating an illegal motor vehicle.
The bike squads in Germany are no fools and are regularly making examples of obviously overpowered "250W"ebikes (which could be legal if they had a moped plate and all the other items required for fast ebikes)
@@velotillthis is why the laws are a bit dumb. What should really happen is there should be a law on use of peak power to allow fast starts and uphill runs tied to the amount of torque provided by the rider. Fast starts for 10 seconds up to 10 kmph on flats (until you pedal past it) and during cornering to get you out of trouble and when hitting an incline allowing the peak power to stay on for as long as you provide enough torque to keep up to the maximum speed llmit of 25 kmph.
1:27 Yep, a big 10 ton trolleybus has an electric motor rated at 100kW. That low! But that is the continuous power. And trust me, during acceleration from standstill, the motor drives much more current than 175A (runs at 600V). That is the reason why there are components limiting maximum current, as the motor would happily take all it can get. And yet, differentials and axle reductions wear out sooner on trolleybuses than on buses. And if the regulator malfunctions, a trolleybus can easily do a burn-out on a dry paved street. Of course, do it three dimes and you can replace the whole axle, if the CV joints on the shaft between the motor and differential do not break sooner. Or you blow the circuit breaker in the trolleybus (should break around 380A, but that is only theoretical) or you trip the breaker in the electrical substation feeding the section where you draw your power from. If you had no protection circuits and a very powerful source, applying 600V directly into the motor would most likely result in lightnings flying out of it and ripping it from the frame of the trolleybus, destroying everything between it and the wheels of the driven axle(s).
The first time I watched it I didn't understand, I had many doubts about... . now it became clear as water. thanks a million
WOW, Thanks a lot! As a retired electrician, Your explanation clicked 100%. Something else I see is batteries being rated in watts with no reference to amp hours. Often digging for other sources, I find the '360 watt' battery is 48V and doing the math get 7.5AH which is kinda small... Just liked/subscribed and bookmarking this video!
im unsure tbh
360 watt would refer to the motor power the battery should be rated in AH
however what I think might be going on here is for reasons I don't know they could be rating the battery in watts referring to the motor its suitable for for example calling a 32 volt battery a 250-320w battery because that's what you mostly use for those and calling a 42v battery a 500-700 watt battery with a 72v battery being a 1000+ watt battery
for reference my bike is specced as follows
350w motor
32v battery
11.5ah battery
if we wanna rate my battery in W/h as opposed to A/h my battery is 368W/h in capacity
but generally when it comes to ebikes if its talking amps there referring to the AH of the battery
if there talking watts its almost always the rating for the motor
and volts being what the battery is delivering
there's a whole thing for over voting the motors to get a lil extra performance as well as going for higher voltage batterys to reduce charge times as all chargers are limited by there amp ratings so upping the voltage is a easy way to get more watt hours into the battery faster without pushing more amps I've even seen some ellect to install 72v batteries and regulate them down to 32 to benefit from having a smaller battery and faster charge times but still having the range a larger lower volt battery gives them
@@Sarge92 That's a lot to wrap one's head around... I note that 'A' also refers to controller ratings. We could really confuse things saying my T42 is only 1.1 KVA peak... If a controller is rated up to 72V and being used on a 48V hub, what's the risk of going in series with a 12V agm with the 48V li-ion to get 60V operating voltage?
The battery rating in Wh is more honest than giving A*h, as the Wh charge actually defines the amount of energy stored in the battery. A good comparison factor is the battery consumption in Wh/km or Wh/mi. Giving only Ah rating (without the voltage) is deceitful. Giving Wh is honest. Big brands always give the battery rating in Wh as not to deceive the customer.
@@StefanMikulski You say "Giving only Ah rating (without the voltage) is deceitful".... I submit, So is Wh - (without the voltage). 360WH could be 36V 10AH or 48V 7.5AH... Speed comes from voltage. VA's or Watts is actually 'power' giving an idea of how long a load will run. Or, in the case of a motor, it's hp rating since 742W=1hp.
@@johnw65 speed comes from voltage? How comes my 36V Specialized Turbo Vado 6.0 can get at 45 km/h (28 mph) while a derestricted 48 V Specialized Turbo Vado SL can only get at 34 km/h (21 mph)? No, the voltage is irrelevant here. Speed comes from the motor power, which is mechanical 520 W peak in the former and mechanical 240 W in the latter. The speed also affects the battery energy draw. That's why the former battery is 604 Wh (36 V 16.7 Ah) and the latter is 320 Wh (48V 6.6 Ah).
I know most are watching this for the knowledge of the ratings, but this has actually taught me a lot about battery building. A concept I never understood was the max wattage rating, and now I understand, its just the max current the battery will put out multiplied by voltage.
Thank you for your clear explanation of the power levels that’s really been a great help. Thank you so much
🌝🌚
You should run a non profit association that lays out a spread sheet of the bikes and all their true non biased ratings. …you know the truth about these bikes. Well done video!
Finally a honest and clear picture for a newbie!
My head hurts
The ultimate ebike guide please,if I do not win a book this time I will buy it. Great video
Finally, someone explained those rating, thanks
This would be a great tutorial lesson put into a full series. Explains things in an everyday way of understanding.
Thank you! I'm getting a DUAL motor, DUAL battery E-Cell Monarch 1500 and now I know how to find the real power of each motor.
You forgot to mention that a particular motor designed to go with a specific voltage will not put out more power just by changing the controller, the voltage will have to go up, which means changing the battery as well as the controller. Ohm's law hasn't changed!
That’s totally wrong. Not only have I swapped out batteries from 48V to 52V, I’ve swapped controllers after switching to 52 and my CLyte 3540 (rated at 1000W) and upping my controller from 26A continuous to 35 continuous definitely puts out more power. There are literally thousands of examples of this to choose from, not just my experience of riding my DIY ebike 30,000 miles. Yes, it is more susceptible to heat (loss), but it’s certainly not all lost to heat. I assume you don’t have an ebike. Ebikes.ca has a simple motor calculator and you can input values for many types of motor and controller combinations and see the data yourself.
I will increase the current from 48v×10a eg..to 48v×25a
What you call power is the torque which is a function of electric current not voltage. Varying the voltage would vary the speed. Amps = Torque (more powerful), volts = speed (faster)
During my studies for electrical engineering the lecturers told me that the advertised motor power is usually mechanical. the mechanical power is calculated by multiplying angular velocity and torque. Mechanical power is the power you get from motor. The power you were talking about was electrical or the input power.
I love how continuous and peak power has an excellent explanation to them, telling you exactly what they're about, then you get to nominal power and it's basically 'this means nothing. it could be true, it could be false, and even if it is true you won't know "how true" the rating is unless you test it.' It is pretty hilarious and i can see where the frustration can stem from that.
nominal is just a label to please lawmakers
Very good explanation of "power". Keeping it simple using VA can help those not familiar with end to end input to output and the various losses along the way. Something to consider is the fully charged battery versus the nearly discharged battery. Power is greatest when the battery is fully charged and is minimal with a mostly discharged battery.
Sooo.. My Super73 SG1 (EU version of the S1), has a nominal rating of 250W, which is the maximum allowed wattage in Europe. The motor also says 250W etc. However, having a 48V battery, and the controller's current is rated at 10A with a maximum current of 20A, it's very obvious that this is a 500W motor with a peak at almost 1000W, which is the same as the original American S1. The European version is electronically limited though, but I've unlocked it by plugging the US throttle in, and I'll just say that if this is "250W", then it's the most powerful 250W motor in existence 🤣 Ain't complaining though!
3 people bought an underpowered bike.
lol!
This is my first time to one of your videos. I’m subscribed!! I understood everything while you talked, but need to listen a couple more times to really understand.
I’m shopping for my first ebike. It isn’t easy. But, you have helped a lot!! Thank you! I’m going back to listen to your other videos! I needed a white board with your numbers on it. Visual learner, here. Good job!
Thank you this clear explanation! Usually, when people ask for the power of a bike (or car), they want the max (peak) power, like with petrol engines.
Wish this video was there 3 months ago when I was struggling to understand these things, thank you! :)
this channel is quickly becoming one of my favorite youtube channels, this video is extremely informative, i dont yet have an ebike but my father and i are both interested in getting an ebike so we have been trying to soak up as much info as we can before purchasing our first ebikes, thanks for the all the informative videos you put out there :)
Build one. It's cheaper and you get to know how they work
@@marcus.H that would be nice, however that's not currently financially viable for us
@@acehighdan sorry to hear that.
Hopefully parts will become cheaper in coming months.
One price of advice I would give for those just starting out is that if you pick up a Liitokala hoverboard battery from AliExpress for $25 you have got a sufficient battery to get you started with a 36v kit.
If you could do a shift extra each week at work, you may be able to save up the $150 needed for the motor and controller in a short time
Or wash cars or Windows for money. Or now lawns
Love your channel. Awesone explanations.
So look at these stats and tell me if Im right...
Motor rated 750 watts.
Peak 1000 watts.
Battery
48V 20AH (960 WH) lithium battery
Controller
48V, 25 ± 1A; 12MOS
Am I correct to assume that the controller at 25 plus or minus makes up the difference between continuous and "peak" with the +5 amps beimg pumped into the motor to produce the extra peak 250 watts which ultimately overheats (at duration).
If I'm correct, I see why manufacturers are tweeking out another 5 amp controller over 20 amp battery in those (required) situations. Also, ambiemt temperature plays a crucial role.
Customer:How many watts?
Manufacturers: it's complicated...
I mean i would make the motor faster than needed too and then use that for acceleration with speed limiter 😂 it just makes sense🤷
This is my random comment, The Ultimate Do It Yourself Ebike Guide.
Thank you for this video, it explained a few things I was trying to figure out. 500W 32kmh/20mph limit where I live.
Yes & Motors have torque & power curve. A hub motor may find life hard turning slowly on a steep hill & heat up fast, but a mid drive is geared crank speed, so should be in the middle of its design range hill or flat. & its also important to remember the gearing factor difference between Torque for a hub motor & a geared mid drive.
Thanks for your clear explanation of ebike power. I’ve been researching the subject for a couple of weeks, and yours is the best, most straight forward explanation yet. Again, thanks. Please keep up the good work.
With motors I just look at the newton meters of torque and the Rpm’s after checking the volts and amps. Thanks for the video
Very enjoyable and clear explanations of a topic that is usually portrayed as confusing and impenetrable.
Looking forward to your DIY motorcycle conversion book and video series!
First class and full marks - easily one of the best explanatories I've ever seen. Thank you very much and happy travels (remember: "No helmet? NO WAY!").
I have a question
About DC power cable? 36v up to 72v, 70ah
Must put a fuse on there
With a controller from 3000w up to 6000w
How can I calculate which fuse should or not
Or does the controller do that, protection of + power cable
Think this is important
Thanks
You make good videos and very educational
Thanks for explaining some of these terms as they apply to the ebike market place. I just recieved my T-1 replacement and didn't understand why the new motor was labeled 250w. Now I do.
The basic direct drive hub motors like violamart have the same direct drive hub motor but the controller varies, it could be sold as 500W, 750W, 1000W, 1500W or 2000W with only the controller varying and the hub motor remaining the same. How is that motor rated. Also if you buy lets say a 1000W version and use it with the minimum size battery it will accept about 48V at 12Ah in the road legal mode it is 250W approx (more like 300W) but if you disconnect the wire you get a 50% boost to 450W approx but the battery can peak at about 960W (20A) output for about 60-90 seconds or about 700W in road legal mode. It's confusing as clearly the battery BMS and controller and motor are not at the same level. I guess the BMS dictates the actual power the motor can receive, the controller could handle more and the motor itself could handle much more. I'm not sure what the nominal or continous rating of such a hub motor is but I guess at least 1000W. I've heard of Bosch motors easily peaking over 700W despite being road legal but many would view the Bosch as road legal and the home kits as not and its one factor why people pay more for a Bosch bike as they worry about the legal implications of a crash with a kit motor hub. The law seems a mess. However here in the UK I don't think anyone has been prosecuted with a home kit and you wonder if the police just check that it doesn't assist beyond 15.5mph because its the only simple test they can do.
I have the 1000 watt voilamart hub motor, and it peaks around 1200 watts according to the screen. I bought the voilamart 1500 watt controller instead of trying to play with the internal shunts on the stock controller. It has been sitting on my work bench for over a month now, cause I wasn't sure if the hub motor would take it or not (wire size)... I wish Micah would respond to comments... I think I should be ok as long as I don't full throttle it, I just want some extra torque on take off
@@chrisnmichelle0218 Can I ask what battery you are using both volts and amp hours plus if you know what peak current it can deliver for how long? Which cells are you using if you configured the battery yourself? I have the yosepower 48V 12.5Ah hailong case battery pack which uses Samsung 2500mAh cells which allows a peak current of 20A for 60-90 seconds. As stated above pretty much the minimum the 48V 1000W motor will accept which I think is stated as 48V 11.5Ah minimum battery. I use it in the restricted street legal mode partly due to legality but also because the battery is such a low capacity for this motor.
@@bonzobanana1 16s 1p 48v 20ah lifepo4 BTR power battery (www.ebay.com/itm/282691708617) it is made with lifepo4 pouches, not cells. 50A continuous discharge, 100A max discharge. The battery is great, but it weighs almost 20 lbs and I have to mount it on a rack behind the seat which throws the weight balance off. I have been buying 32700 liitokala lifepo4 (m.aliexpress.com/item/4000073953939.html?pid=808_0000_0109&spm=a2g0n.search-amp.list.4000073953939&aff_trace_key=0f27108c4dae4f51866478090c8a265e-1598364242794-04812-UneMJZVf&aff_platform=msite&m_page_id=6236amp-8afh0fKpUqPr1GppmYPgnw1598364304447&browser_id=3d094fe9d33b4a2fba89779d51150c11&is_c=N) 3.2v 7ah batteries, with continuous discharge rating of 35A per cell. I plan on building a 16s 3p battery with the 32700 batteries, and a 50 amp bms for it. That would get me 51.2v 21ah battery with a continuous output of 50 amps limited by the bms, I plan on using a bms made by Daly, as they have great ratings. I'm kinda sold on lifepo4 batteries because they have a much longer lifespan of 3000 charges (I don't ever drain my batteries dry) and just being a safer and more stable composition where I don't have to worry about thermal runaway if I push the batteries really hard.
In finland can be 1000w but 25/kmh. But you have to pay insurance if the bike's power exceeds 250w or if it goes pedalless.
Hey, just a heads up. Several of your links to Aliexpress are dead. The 18650 cells link goes to a charger. The 1000 watt complete kit is dead. There are others that are dead, just some housecleaning to do with your links. Thanks for the videos! I'm a fan.
Wouldn't torque increase as you increase the operating voltage though? So the torque rating would only be applicable for the listed controller / battery. If I throw a 52v battery in a 48v controller, the torque produced would increase
Thanks
Reminds me of some lakes will have a limit of 10horse motors. But some people will put a 10h cover on a 15h motor.
The power rating system reminds me of the Japanese gentleman agreement between the Toyota supra and Nissan GTR when it comes to horsepower making in the same
Hi sir, I still new and planning to buy an escooter. Found a escooter with two different model. Which one is you think much better?
A. 48v 10ah with 500watts
B. 48v 13ah with 1000watts
ok, i have a Addmotor trike M-340, 48V 17.5 ah battery with a 48V 25A controller, could i upgrade this and if i can what too ?
You talked about this several years ago (I think too, it’s also in your book) good to hear again. I think you put it better here. It’s not as text book more layman’s terms I guess. Same but more relaxed and I think easier to understand. Good to hear again very important. And yes we do benefit if we know how to take advantage. That we can (w/aftermarket controllers) put together a bike that we love to take for a ride!
you can easy put 350watt on a 250watt motor as long as your rides aren't very long(time depending on ambient outdoor temp) my home work rides take max 20 min, about 6km(aprox 4miles)
Very well explained, thank you Sir. Question/s how/where do find the controller max output? where do you find the motor's true continuous output? Could you find out from the components cereal number?
Great info.....
What about matching Batteries with controllers regarding Amperage?
The battery continuous Amperage should always be higher than controller continuous Amperage rating?
Micah-this was helpful regarding power, with good examples. I would be interested in hearing a similar approach to torque ratings. Thanks!
I just ordered a Ristretto 512. Battery is 52v 30Ah.
Motor: street legal 750w and race mode 4500w peak, which is claimed to be 40-45mph.
52v x 30Ah = 1560V. Does that mean that this motor can run at 1560V continuously without overheating? Therefore I would not be able to ride the bike at 40-45mph without the motor overheating?
Thanks Peter for clarifying electrical power ratings and some extra tips (torque).
I love you dude you've taught me so much and getting all this info makes me knowledgeable enough to build an ebike
ADO are interesting on this front. The ADO Air 20 has a 250W battery and 350W on the international version. However, both are apparently marked as 250W on the motor. It lists as 9.6 amp hours (36V battery). Which means it is basically closer to 350 watts peak on the international version while artifically limited via the controller on the EU version and does not include the thumb throttle. Their Beast ebike has a 250W motor listed ONLY but is 14.5 amp hours (36V), which means it peaks at around 522 watts. Lots of shennanigans going on with many of the manufacturers especially people like Engwe ;)
Also, a couple other things:
European "continuous rated power" isn't continuous power! It is, to quote Regulation EU No 168/2013 Article 3(35): "‘maximum continuous rated power’ means the maximum thirty minutes power at the output shaft of an electric engine as set out in UNECE regulation No 85"
And "maximum thirty minutes power" from that UNECE regulation: ""Maximum 30 minutes power" means the maximum net power of an
electric drive train at DC voltage as defined in paragraph 5.3.1. of this Regulation, which a drive train can deliver over a period of 30 minutes as an average"
Additionally, there's test procedures in that regulation that define it better, and where the loophole comes in - the power level must be the manufacturer's best estimate of maximum 30 minutes power, and the RPM must be in a speed range that allows greater than 90% of maximum peak power (which is determined in a separate test). If the manufacturer estimates too high, of course, it'll fail the test and they'll have to re-run it, but if they estimate too low, it'll pass.
The US regulations not actually saying what power rating standard is in use make me think the safest bet is to assume the more (but not the most) restrictive interpretation - 750 W peak output power. I don't think any of the vehicle regulations in the US are actually using continuous power (whether over a specific time or indefinitely), but then the US doesn't usually restrict power output, either, outside of e-bikes and state laws restricting what can be used as a moped/motorized bicycle/scooter without a motorcycle license.
Then, there's one problem with your methodology of determining peak power: efficiency. So, just because you've got 36 V, 15 A coming from your battery doesn't mean you have 540 W coming out of your motor. If your motor/inverter system is 85% efficient at peak power, you've got 459 W coming out of the motor (and 81 watts of heat that your controller and your motor need to dissipate), and that's your real peak power. (There's additional drivetrain efficiency considerations downstream if you have a mid-drive, but my understanding is that power regulations care about motor output, not wheel output.)
US goes for Continuous power. Rating the motor by peak, is incorrect for it's performance. Peak is the RPM and torque a motor goes through before it reaches it's end power point, then tapers down in power. So once it's up to speed, it's not at it's peak power anymore. Same as Gas cars,etc. If they ruled for Peak, Electric/Gas devices would suck.
It's like saying, This car can only have 500rpm and such % of torque. You realize how SLOW that car would be to get up to speed? It'd be like a snail trying to get up to 40mph, in 20mins.
So if a state has a rule of power of a 750watt motor as limited. That is continuous power rule. Not Peak. The motor can have 2x more Peak, because that start power the motor goes through. Again like a gas car,etc. It's the start of the motors run to get whatever it's pulling/pushing up. Then it lowers down to it's continuous power performance which runs at a stable set.
Nobody cares and no one reads your comment, stop looking for validation of your knowledge level in UA-cam comments, it's very sad and childish.
@@TheAvkdutch You're a great example of how dumb the world is. "Will listen to this stupid twit on this epic website that doesn't know crap, But not to someone who knows the truth on a comment."
You should've just never commented, Cause you just made yourself look like a fool and just showed everyone else like you how dumb they now can see themselves.
Auto manufacturers underrate their motors too. The 06 Chevy cobalt SS LJS supercharged 2.0l motor is advertised as producing 215 crank hp. I assume this if to keep insurance rates low, because they routinely dyno at 235hp at the wheels before any mods. I'm happy to get an underrated motor in my e-bike because excellent reviewers, such as yourself, make head to head comparisons revealing the "truth in advertising" very quickly.
One of your best videos! Very well explained, I wish I knew this before I bought my first ebike a few years ago.
I have a 500 watt 3 speed 90 pound throttle controlled ebike and a 52 pound 350 watt pedalec fatbike. Both seem to produce about the same power. The fatbike specs say 700 watt peak and goes from 0-30kph in about 7 seconds. Considering the weight of the fatbike tires, it seems to be a stronger motor and the taller gears allow me to reach road bike speeds of around 40 kph under ideal conditions. Had expected the 350 watt to be slower but it is comparable to the 500 watt ebike. The plus side is that I can use the 2 frame mounted fatbike batteries on my 500 watt ebike with a 2 pin DIN plug plus 2 batteries on the 500 watt ebike. This allows me to use 40 pounds of battery on the bike which I expect will give me somewhere around 100 miles range with pedal assist. I have 2 batteries mounted on the frame bags and 2 fatbike batteries in panniers. should provide decent battery range when towing my tent trailer too.
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Wouldnt power be either controller voltage * phase amps OR battery voltage * battery amps?
Phase and battery current would only really converge when the controller is at 100% duty cycle at high RPMs where you're back EMF limited
At lower speeds youd be limited by either the phase or battery current limits so by definition the voltage at the motor would have to be less than the battery voltage, if we whacked the motor with full battery voltage at 0 RPM, current draw would approach infinity (well it would approach the short circuit current of all the wiring) and fry the controller.
Excellent information, I’ve been using the torque number and 750 W as my comparison point since my neighborhood is hilly. My driveway has 7+ feet rise of elevation 😂
Hi Micah, you have a great chanel, Im looking at building a water jet surfboard using a 300A ESC with a 9000w motor, Im looking at making 24v battery, with 7 cells in series and 8 cells in parallel. Im looking at using 56, 21700 SAMSUNG 40T, 4000mah with a Maximum Continuous Discharge of 30A per cell, I'm hopefully aiming on not pulling no more than 150A, from the pack, would you use say a 200A BMS or would you split the cells into 4 packs and use 4 x 50A BMS's
great info, question I have folding Tesgo ebike and display does not show actual volts can I wire to the backside of battery wire going to controller and out to a voltmeter to see actual volts? My controller is in the frame, and I can take off the matting side and get to the positive and neg cables. I could drill small hole and run wires up to my handle bars.
This is a very helpful video, Thank you!
Question, I have a Heybike 500w (48v 12.5 amp battery) Heybike states that my Mars Ebike has a peak power of 1000w and yet when calculating the figures I get 720 watts (a 15 amp controller x 48v=720w) not 1000w? How is this possible? Is Heybike overstating their specs.? The stated torgue rating is 50-60Nm.
Nice informative presentation. A couple comments.
1) Does anyone know if the motor manufactures are specifying a maximum continuous stall torque, something else?
2) In shopping for a ebike, I calculated the miles and elevation I would typically be doing here in Portland Oregon. It came out to 70 miles a week and 4,000' vertical feet. The dealers that addressed that issue were unanimous is saying"you need the biggest motor and battery you can afford", and then advised it will probably come up short on my hilliest days.
A really useful tutorial/vlog. I had wondered why there is so many different claimed power outputs
Is there a torque rating/watt power chart somewhere? That would be great to know.
Also, some guys on the endless sphere forum were telling me that motors have a volt rating of their own. Is this true? Cause I though the voltage was relative to the battery pack you hook it up to? I certainly can never find one when I'm buying or labeled on any of my motors.
Good info, been messing with ebike for a while and came to these ame conclusions.
However I have also read that torque numbers can be fudged and interpreted differently so also not a reliable number to focus on.
Best bet is to look at all the numbers together and also look through forums etc to see what people are saying about a particular motor you are interested in.
Mid drive is tempting me but for reliability I just convertedmy mountain bike with full suspension to 1kw hub drive and it's a nice powerful fast ride.
Super informative, learned bunches. Is it possible to run a controller with a S866 LCD set at 48 volts with a battery that is 36v? Or would having the system set to 24v with a 36 volt battery work at all or make the bike go faster. I have a Bolt Pro with a aftermarket 24/36/48/60 controller and seems like I'm stuck at approx 20mph. And that's with the learning loop disconnected which I was told would free me from those 20mph bonds. I'd appreciate your opinion on what I should do next. Thx in advance, Dan
Imo it really depends where you live, if it's flat-land almost any ebike can push you but if hilly that's a totally different context, I have a bike with a Bafang Ultra that when you give -it the gas draws 4 to 7 times the energy that a typical European bike does, even a big battery pack can't give much range at that rate...
Hi Micah, would you agree then that a 500 watt motor in the rear wheel with (usually) 7 gears is going to perform the same as a 500 watt mid drive motor also with 7 gears & all other things being equal as well? There seems to be this belief that mid drives perform better than rear hub motors but I believe that is only true if you are comparing a Mid Drive to a Direct Drive Motor without the same gearing. Your opinion please.
Great video very informative. I will be looking into this further.So i should be looking for continuous power.1200 watt motor ,with a 15 amp controller equals 18,000 or1200 times 48 battery volts equals 57,600 . What am i really needing to know here? I ran my battery down with an incident i had with a flat tire an i would like to no why that happened also?
Your calculations are way off. A 48V battery at fully charged is 54.6V. Suppose somehow your 15A controller draw max current that would equal to 819 Watts, so if you have a motor capable of 1200 watts continuous it can never get the juice to run at 1200 Watts, unless you upgrade your controller to a 25A one.
This is the most in-depth explanation on this topic to date.
I can't seem to find the answer to How can you determine/verify the exact rated watts of a controller?? If I buy a 1000 watt controller how can I be sure it is what is says it is. What electronic components dictate the watts of the controller? amps I can check with a ammeter. Watt output is amps x volts. That can vary regardless of the watts of the controller.
If you can physically gain access to the controller, it's printed on a sticker. It depends on where it's located and the difficulty in getting to it. To get to mine, all l had to do was remove 6 screws and the controller was right there, but protected from the elements.
Hope that helps.
I hope you will answer my question
Should the controller be equal in? Amp
Matched on battery of,
Quantity in amperes
What is the correct ratio in amps
On 2 motors from 3000w up to 6000w
Can you help me with this
I do not know ?
Good day to you as far i can understand on your explanation tha combination i have to run a motor hub is way not to good, i purchase a 48v 350 motor hub and using a 48v 500w controller and power it with 48v 13s 4p 16850 battery, please recommend the good combination with this voltage. Thank you
Just got my first spot welder from banggood. Tried it out and love it already. Cant wait to make my first pack thanks to your books!
Which one did you get?
That is going to be my winter project, I have been ordering LiFePo4 32700 batteries, to make a 16s 3p battery pack. Probably will go with a Daly BMS. I'm also curious what welder you got, and what thickness of nickel you plan on using
Here are results of that tab welder. Now im not an expert on welding but maybe someone can answer my question on it. Again this is a first time thing for me and maybe I bought a bad welder but if anyone know's more about how good or bad I did id love to know. Thanks again!
ua-cam.com/video/LERZ14QSksE/v-deo.html
It's have a bafang 750w motor and 48v 17ah battery setup. I was running it on a single speed drivetrain 44/14. I have been told it will damage the motor and is putting to much strain on it. Would this be the case?
Just bought my first ebike. Waiting to get it. Looking to buy solar next to go totally green.
Micah, I've been looking for an explanation of what "nominal" really means, thanks!
I still did not get it🥲
Maybe you can help i have a Super73 RX and every time we do this huge bike ride all over NYC im getting range anxiety and everyone fights for the electrical outlet that's available. My question is can i put an additional aftermarket battery and will my bike recognized the BMS on it? thank you in advance
You will be able to make a video where you show how to connect a standard ebike monitor to two controllers?
Great explanation of ratings on the electric motors. Easy and clear.
So over what period of time does the motor have to get max 250 watt according to EU regulations? And how do Bosch and others follow that when their max power is 600-800 watts? For how long will it stay on max power until it limits the power to comply with the regulations? Or do they just ignore the regulations and downrate the "nominal power" while the continues power in reality is much higher?
Hi Micah, just a little bit of clarity please on power. Isn't this based on what cells you have rather than the controller? For example an E-Bike with a pack 37V, 17Ah, gives 630W max. The controller might be rated to handle 750W but it would never receive that amount right?
So when i buy a battery and it reads 72v 33ah. The 33ah is the size of the controller it can handle. 72 x 33 = 2,376 . I have 2x 5000watt motors with two 50a controllers. I can use a 96v but that’s just to much power.
Pleasant surprise, companies delivering more power than they are promising on paper. :)
Does it matter if you run a motor at a higher voltage than intended though? Aside from cooling the total power I can't see any reason a simple electric motor would mind more voltage - within reason obviously. All the sensitive electronics are in the controller as far as I understand. In the extreme the engine parts might not tolerate the extra physical strain of more torque, but I doubt that 250w and 750w notors are much different in physical construction. I'd love the input of an experienced builder here. This is not advice - just a hypothetical based on my understanding of simple electric motors.
Pretty good. I find it helpful though to go to the next stage as what we are trying to do is compare the human power at the back wheel compared to the assistance power at the back wheel. And for that we need to talk about temperature and efficiency, as obviously not all motors and controllers are the same, plus of course efficiency is a map rather than a fixed number. If we know the efficiency at say 25C of the individual components and calculate the battery to wheel serial efficiency by multiplying each component by the next we end up with the actual power at the back wheel. Volts x Amps at battery x serial efficiency.
If I had the spare cash it would be fun to use a powertap hub to see the combined rider and assist output at the wheel and a powertap or similar at the pedal crank to measure rider input. With a few simple sums we’d be able to genuinely determine the total and rear world power split.
Enjoyed your battery book. Thanks.
I have been watching your videos for a long time and thanks for your information I learned a lot throughout time!!! I became scooter technician and a lot of information came of watching your videos!!! Thank you my brother as always! Great content!!!
why torque gets so much attention? you can anyway use a gearbox and increase your torque as much as you wish (unless you do with wheelhub motor) . I'd be more interested in efficiency of a motor in various working conditions
A good tutorial. However, there is one thing that has been slightly overlooked, which is the electrical vs. mechanical power. The 250 W continuous power is not the electrical power (V*A) but mechanical power, that is, (V*A) * mechanical efficiency. Contrary to what was said in this video, the mechanical efficiency would rather be up to 80% (not 90% as it was explained here). Let us take one of the few big brand motors with actually low power, which is Specialized SL 1.1 motor by Mahle, with torque of 35 Nm. The continuous power of that specific motor is equal to the peak power, and it is 240 W MECHANICAL power. It is possible to digitally measure the electrical peak power of that motor, which is 303 W. Meaning, the mechanical efficiency of that motor is 240/303 W = 0.792 (79.2%). Now, if a cheap motor manufacturer claims 750 W of continuous power, they probably mean the ELECTRICAL power. Hence, those cheap motors probably deliver far less of mechanical power than advertised.
Very well written - that is the most misunderstood part.
Always great!!!
I am new at E biking. I just now put a 118 miles on my bike. I'm still trying to figure out maintenance. Where do you get spare parts we bought cheap E bikes? Walmart specials $500 Hurley K.
May I ask, What would be a good size (Battery/Controller) for me (237 LBS) with 1000W befang front hub motor. Want max of 28 mph but will not be going that fast 99%.?
Question.. does enabling dual motors on a scooter uses less battery? Because if the front motor is off, it create drag so the back motor uses more power? Is this myth true? ty