#askgmbntech Can anyone explain how e-bike racing works? Are speeds regulated? What tactics come into play when everyone can crank up to the same top speed? Is it simply a case of the lightest rider wins the hills, or a competition of aero and line choice? or are there factors I'm missing?
for the guy with the bad lower back i had a similar issue after a back op and this post saved me .....SR Suntour SP12 NCX seatpost ..... its adjustable to your weight and would totally recommend it
fwiw. regarding the question about Moto vs MTB tyres, there are actually a huge range of off-road Moto tyres from the respective manufacturers - featuring any number of different tread designs/compounds etc. specifically for the conditions you might be riding: soft loose / sand / hard pack / desert / enduro / MX / 'adventure' whether they are also street legal (FIM) or not... I'd suggest there are just as many options out there as MTB tyres, although like anything not all of them may be available in any one particular region/market.
I run an XC set and an Enduro set of wheels on my hardtail and I use the same hubs specifically so I could just pull the cassette each time. Not because I'm clever but because I am cheap. XX1 cassette are pricey!
Dirt bike tire R&D has been around much longer than mountain bikes have existed and is therefore, not surprisingly, more "dialed", and there are tires specifically designed for all kinds of conditions. However, there are also newer innovations all the time (such as newer "gummi" compounds). The differences are, aside from what was mentioned about unsprung weight, is the overall weight, the need for the rear tire to maintain traction under much more forward driving torque (which gives a dirt bike the opposite knob orientation than is usually found on mtn bikes - i. e. the sharp edge always faces forward [as seen from the top of the tire] on a dirt bike), and traction in cornering under much heavier loads. Also, there are many more differences perhaps than what you are noticing if you look closer. Mud tires are a harder compound, and the knobs are spaced farther apart so that they 'self clean' better. Hard terrain tires are a softer compound for grip and the knobs are closer together (for more grip). Racers choose tires relative to the expected conditions of the track/course on race day. The average rider chooses the tire that fit the most common conditions they usually ride in. Some front tires have knobs along the edge that are slightly turned so that tracking is improved while rolling through the turn (helpful in tight hare scramble courses). Also, as with mtn biking, there are different tires for different "disciplines". There are tires specific for Dual Sport that would be more street accommodating. Then there are true Trials tires, and then Enduro set-ups, Hard Enduro set-ups, "Woods" racing, outdoor MX, Super X and so on. Some tires can accommodate a couple different disciplines in the right conditions, but no tire can do all of them, just like in mtn bikes.
Michelin uses similar types of compounds all across the two wheel range, the MTB Gum x compound is soft and extremely sticky like high end front MX ...
My carbon frame had a warning not to clamp the frame. Fitted the starcross 6 MUD tyres to the YZ, and it gives so much confidence when railing it. Been enjoying the channel, Thanks.
Saddles and support is a huge piece of knowledge I don’t have the experience in, have arthritis (RA) In my hips. Support and comfort I would like to understand more about the options, this was really helpful to start, and see what my local bike shop offer 👍
I'd go to a fitter and have your saddle checked out, mine was 20mm too wide and the wrong shape which was causing saddle sores, pain in the perineum and hips.. A narrower saddle with cut out and a slightly different shape stopped this because my sit bones were in the correct place.
Ive always had aluminium frames and clamp on the top tube, you only need to tighten it lightly just to hold it in place. Ive never understood why you would clamp it on the seat post as i would have thought it places alot of stress around the seat tube area, especially with carbon. frames.
Long time bike mechanic here: Idk if I would advise the general public to clamp their bikes on the frame. Pretty sure many less experienced riders with cheaper workstands will just clamp the frame tight to the point of over-compression and damage the frame. As long as the dropper post is fully extended, it should be safe to clamp it. If you’re not sure, you can also clamp directly to the outer shell of the post. But I have seen so many people who broke their bikes by clamping them to the frame… So hard no from me.
@@THRENO82Yeah, I've only ever owned aluminum framed bikes, and just barely clamp onto the top tube at the balance point. I've tried clamping the seat post, but the bike always pivots to a weird angle unless I make the clamp superhumanly tight. I'd much rather barely clamp at the balance point of the top tube than reef the clamp on the seat post. I guess if I ever go carbon I'll have to retrain myself...
6:56 i purchased a pretty cheap "suspension" seatpost on Amazon, it's only got about 5-10mm of travel but it does help. The only thing to lookout for is the intended weight rating for the rider. Most of these seatposts are intended for heavy riders that weigh 250+ lbs. Myself as I guess a light rider coming in at 185lbs found it difficult to find a seatpost that actually had any kind of give when riding. I'm actually planning on overhauling my cheap suspension seatpost later today to hopefully help it get a little smoother. Wish me luck, hopefully I don't end up with a tension loaded spring being shot into my face.
What on earth are you on about??? It makes no difference whether or not your pads are bedded in on your original wheelset. They will require bedding in on the new disc in any case… and then when you swap back to the original you will need to bed them in again.
I ran 2 wheel sets on my old 26" 2x10 stumpy for years. Each had their own cassette and rotors and it worked absolutely fine. That said I started with a new chain and new cassettes on both wheels, and swapped between them quite often (ran 1 set in the week for riding to work, and the other set for actual MTB stuff). About to do the same thing with my new 12sp stumpy, saves trashing expensive mtb tyres riding to work and back with minimum faffing about..
I would have no qualms about swapping wheels and cassettes. And no, I don’t feel the urge to send my chain out to Lawrence Livermore Labs to confirm I’m within in bounds. This is the wild abandon that comes with using mid grade components.
Tire compounds make a huge difference... For hard Enduro moto they use a gummy tire which has a softer tread that transfers the torque more efficiently through an obstacle maneuver like bliping up a rock garden... I don't know if there's an MTB equivalent, but tires for observed trials are usually designed for trials. You don't have to get a trials specific tire, but it's more likely your going to slip out on a precarious obstacle because the sidewall and the compounds didn't respond to the surface in a beneficial way. You can put a grind on the rim or get bigger rotors for better braking but you can't make your tire any more sticky with out making it that way. Watching some of these emtb Enduro racers it's looking like they're going to need a similar range of options. They're really getting after it on those climbs with a much more aggressive attitude than unpowered cross country or Enduro racing. Totally unrelated to MTBs. Semi truck tires being so much larger really illustrate how purpose specific tires behave and wear out much differently than general tires. So much so that you can use the wear patterns to identify other mechanical issues. I've changed enough of both things to appreciate how a $100 dollar tire that's purpose specific on a bicycle is probably worth it over a $20 dollar tire. I've used beach cruiser tires for trials because it was hard to find bicycl trials tires in the US. And the real thing totally changes the behavior of the bike at the back wheel. No more slipping out mid peddle kick when it's a little moist outside. 😂
I'm using 2 wheel sets on my bike and each of them has it's own cassette and brake rotors. I'm paying attention to my chain wear though and never had an issue with this set up.
Ebike specific and certified parts are mostly just a means for the industry to sell more gear. A 70kg rider on a 23kg Ebike is going to stress load the components pretty much the same as a 78kg rider on a 15kg analogue bike, particularly on descents where the motor is largely inactive. The drivetrain is the only area where you can argue the motors could produce more stress.
They’ll be higher stress on the down tube too. Two reasons for this. It is where the weight of the battery is slung. The shape has to change for an integrated battery, doing from a large diameter round or oval (conventional bike) to a flattened, highly irregular shape. The weight of the slung battery along the down tube will add stress at where it meets the head tube and bottom bracket shell. The material in a conventional bike frame can be designed to add stiffness and strength. It’s nigh on impossible to do that with a battery pack, which is not a stressed element and must possess the means for removal and eventual replacement. The comparison you make in overall system weight (rider and bike) isn’t an equal one. Nor are rider weights you quote necessarily indicative in light of statistics. The average weight of a man in the US is 91.5kg. In the UK, it’s 87 kg. Denmark is 86, the Netherlands is 87. Croatia is 92. Canada is 88. Australia is 89.6 (I didn’t want to round up to 90 because it would appear then like I was warping the stats). Not even Japan’s male population has an average weight of 70 kg. It comes in at almost 71 kg (70.7 to be precise). Female weights are closer to 70 kg, but that’s not even the norm in most developed countries. www.worlddata.info/average-bodyheight.php Pro riders are a LOT lighter though.
#askgmbntech seriously, why can't tire manufacturers make tire sizes consistent? I like to run different tire tread designs front and rear but many times (even in the same brand) the actual sizes can differ considerably. I've bought 2.4s that are more like 2.3 and 2.3s that are more like 2.5s. Why can't they just measure the tire and mark it as such?
Hello gmbn crew I have some questions about carbon frames and shock placement I am looking to buy a new bike and it probably will be a carbon frame But in my shed i hang my bike on the wall with an airlock from hiplock Will this damage a carbon frame by hanging it from the top tube ? Also a lot bike i am looking at have the damper placed at the top tube, that wil be hard of impossible to hang like this ? Of so you have ideas or suggestions to work around this ?
#AskGMBNTech Hey you beautiful people over at GMBN Tech, I have a question regarding tire wear. Hear me out please: I am currently running my bike on Assegai 2.5 Double Down and DHF 2.5 Double Down tires. I have used my bike in the winter in very cold weather a few times and I have noticed that the top layer is covered is short cracks. I am inclined to assume the damage is solely to the soft layer of the 3 compound and not to the double casing layers. I haven't lost any side knobs which is a clear indication to me that the tire is holding up very well. My question is, since both tires are holding pretty well and have double down construction, is it safe to continue using them for 1 more summer? The rationale behind my thinking is that bike parks ofter rent out mountain bikes to guests that have worse tire conditions than my current setup. If they are willing to continue using those tires on their bikes and continue renting them to guests where liability is much greater than someone who's riding on their own, then why shouldn't I?
#askgmbntech - let's talk about the dark art of wheel building - is it something the 'average joe' should ever attempt? what is the minimum kit you need and what should you pay attention to?
I gave it a go during covid lockdown just for something to do. It's actually pretty easy, wheels stayed true and round until the bike got nicked earlier this year. All I had tools wise was a decent spoke key. I used the cable tie trick to true the wheel, and the stack of coins / cups trick to dish it, both of which were outlined in the Ali Clarkson video I used as a tutorial. Took me about 3h to do a complete wheel.
#askgmbntech on long climbs I get some lower back discomfort whilst sitting down. I just recently got my new bike and it’s an extra large which I’m just tall enough for ( maybe should of went for a larger ) is there any setup changes I can make to reduce this discomfort. Thanks
#AskGMBNTech I recently rebuilt my Rockshox fork thanks to the help of your videos! The service manual said to use Sram Butter on the inside of the wiper seals when putting the fork back together. Do you think this means Sram Butter would be best to use on the stanchions to pull up dirt that gets trapped under the wiper seals after a ride? Or would a silicone fork spray be better?
Regarding helmets why wouldn't you get the most protective, surely DH spec is the best due to speed and obstacle impact? Making stuff like helmets bike type specific is a bit daft because any bike can reach 45kph in certain circumstances. It would be interesting to see how many viewers actually know what Cat their bike is and what type of trail its suitable for? Finally does upgrading suspension improve the Cat of a bike?
I may be thinking complete BS, but I understand the helmet can work better when it is designed to withstand the type of impact; e.g. DH at speed hitting a tree would need a different rate of slow down than a regular trail rider hitting a rock, so a over-rated lid might not be suitable?
I may be thinking complete BS, but I understand the helmet should be designed for the type of impact; a fast DH hitting a tree would need a different rate of deceleration and penetratation resistance to a slower trail rider hitting a rock?
Where are those pristine and dry fire road trails you’re riding on? I went out for a run last night and almost ran into a thunderstorm…. and the trails are basically still swamps! 😂
😂 the cassette chain not matching 😂 i have the same chain since i bought my bike 14 years ago and changed the cassette without changing the chain and still use it after 8 years no jokes on a 2×9 setup. I climb very steep hills still the chain doesn't slips. I had a brand new bike, new gears and new chains slips it happened to me on the road my foot went under the back wheel of my bike and I opened my leg
@gmbntech yes it happened over 20 years ago. My calf caught in the gears. There was no infection and no scars left now. I was lucky. Thanks for asking 🙂
#askgmbntech Is the maximum user weight rating on bikes something to go by? Is it mostly tested on the frame or the suspension components? Would upgrading suspension from stock to something stiffer, say 34mm to 38mm raise the max user weight? Thanks
@OwenBikeNerd for reference I just bought an ebike from Cube. Mine is rated for 137kg with fox 34 rhythm forks whereas my wife's team action 140 is rated for 150kg with kashima suspension around. Same frames, same brakes, same drive train and same (ish) 29er wheels... If I went kashima 38 would the bike be capable of more weight.. You probably understood me but reference always helps... right? Thanks Owen
#askgmbntech what’s the safety difference between a dh certified lightweight enduro full face and a standard dh “full fat” full face helmet? Are they equally as safe specifically when it comes to bike park riding?
#AskGMBNTech Hey, I have an old Dirtjumper where i upgraded the crankset to a shimano 12x. I also have an 12x Chain… Can this fit on a single speed cog, or can i get a 12x single speed cog? #AskGMBNTech?
#askgmbntech Hello gmbn crew I have some questions about carbon frames and shock placement I am looking to buy a new bike and it probably will be a carbon frame But in my shed i hang my bike on the wall with an airlock from hiplock Will this damage a carbon frame by hanging it from the top tube ? Also a lot bike i am looking at have the damper placed at the top tube, that wil be hard of impossible to hang like this ? Of so you have ideas or suggestions to work around this ?
Ebike certified is all a load of marketing bull. For example I have friends that ride ebikes and their total weight on the bike is 75-80kg. I'm 127kg with my bike and gear and I ride normal components with no issues. Suddenly you have flyweights buying all this "ebike certified" crap when my physical frame and riding style would exert far more stresses onto the bike than any small motor or battery with a 40kg lighter rider. Im 45kg heavier than them and dont need "heavy person certified" parts. They have all lapped up the "ebike certified" crap and loaded their bike with parts that are the same bar a certification stamp. If I can stop an enduro bike on cheap clarks 4 piston brakes at 120kg and 57kph, someone at nearly half the weight can stop an ebike without the need for a logo on their brakes. I'm doing far higher speeds down the trails than them as well due to a skill gap so the Idea that a 75kg setup needs special components simply due to the existence of a motor is just plain bizarre from an engineering point of view. Christs sake, I can hold my throttle on my ebike full on and hit the brakes and still lock both wheels with ease so why would I need a stamp on the product to verify that?
GB #askgmbntech. any idea where I can get 150mm cranks for my specialized turbo levo sl gen 2, it'd be nice if i dident have to sell a kidney to buy them!
#AskGMBNTech I saw a chart from the pros closet and it showed that 54% of XC World Cup wins are riders using RockShox suspension. For the Downhill world cups 68.2% of the winners are using Fox suspension. I this is the case for these two disciplines then why aren’t riders using the more commonly winning brand? I know sponsorships happen and all but don’t the racers want every performance gain that they can get?
Why talk about Ebike standards here? @embn I skip all the parts you blab about Ebikes. These other commenters look like Ebike riders. 11:00 referencing Ebike tires in relation to moto vs bike tires is acceptable, otherwise leave it to EMBN
many ebikes are still just mountain bikes with a kick. it was a question by a viewer asking it to gmbn, they can do what they want? why are you so upset about it? just skip ahead
Let’s be honest. The vast majority of e-bike riders aren’t going to tackle any serious trails. A more sensible answer is that the standards are probably oriented to ensuring the frames stand up to high rider weight. A standard bike frame is usually good for a total of 300 lbs. This includes bike, rider, and gear, so we’re probably talking about a rider weight of 260 lbs on a heavier framed bike with a few add ons, multiple full water bottles, helmet, clothing etc. That all works without a vertical drop. In situations like that, the practical limit is probably far less. Strap on a batter, motor etc., and the bike itself might tip 40-50 lbs. plus, most e-bikes don’t have fully triangulated frames. It gets in the way of some riders’ ability to swing a leg up and over. So introducing some kind of standard for frame strength is probably a good thing for the consumer. Hopefully, those same consumers will progressively challenge themselves by progressively turning the electric assist down as part of a structured fitness programme to shed any unnecessary weight. Saying this as a guy who could lose 10# so rides 4+ hours a week on road and trails completely unassisted.
The question is completely relevant - as Owen pointed out, increasingly shared aftermarket products (suspension, brakes, drivetrain, wheels etc.) are labelled as 'eMTB rated' - which means they tend to be longer lasting and capable of handling the higher torque/power transmission loads that you'd get with an assisted bike. Generally speaking, eMTB 'rated' parts are going to be a similar specification as Enduro or DH components, for the same reasons.
Just the word eMTB ruined my day. Why in the world they can just stick to old trusty 100% human powered bike! If your old and can't ride, then stop! You're a liability to the trail. Im not a hater, its just not right!
Do you have a question for us here at GMBN Tech? Ask away in the comments, and be sure to use #AskGMBNTech for a chance to be featured! 👇
#askgmbntech Can anyone explain how e-bike racing works? Are speeds regulated? What tactics come into play when everyone can crank up to the same top speed? Is it simply a case of the lightest rider wins the hills, or a competition of aero and line choice? or are there factors I'm missing?
for the guy with the bad lower back i had a similar issue after a back op and this post saved me .....SR Suntour SP12 NCX seatpost ..... its adjustable to your weight and would totally recommend it
fwiw. regarding the question about Moto vs MTB tyres, there are actually a huge range of off-road Moto tyres from the respective manufacturers - featuring any number of different tread designs/compounds etc. specifically for the conditions you might be riding: soft loose / sand / hard pack / desert / enduro / MX / 'adventure' whether they are also street legal (FIM) or not... I'd suggest there are just as many options out there as MTB tyres, although like anything not all of them may be available in any one particular region/market.
⬆️⬆️⬆️ This guy gets it, loads of different MX tyres out there just like mtb 🙌🙌
Availability makes life painful sometimes. 😂
I run an XC set and an Enduro set of wheels on my hardtail and I use the same hubs specifically so I could just pull the cassette each time. Not because I'm clever but because I am cheap. XX1 cassette are pricey!
Dirt bike tire R&D has been around much longer than mountain bikes have existed and is therefore, not surprisingly, more "dialed", and there are tires specifically designed for all kinds of conditions. However, there are also newer innovations all the time (such as newer "gummi" compounds).
The differences are, aside from what was mentioned about unsprung weight, is the overall weight, the need for the rear tire to maintain traction under much more forward driving torque (which gives a dirt bike the opposite knob orientation than is usually found on mtn bikes - i. e. the sharp edge always faces forward [as seen from the top of the tire] on a dirt bike), and traction in cornering under much heavier loads.
Also, there are many more differences perhaps than what you are noticing if you look closer. Mud tires are a harder compound, and the knobs are spaced farther apart so that they 'self clean' better. Hard terrain tires are a softer compound for grip and the knobs are closer together (for more grip). Racers choose tires relative to the expected conditions of the track/course on race day. The average rider chooses the tire that fit the most common conditions they usually ride in. Some front tires have knobs along the edge that are slightly turned so that tracking is improved while rolling through the turn (helpful in tight hare scramble courses).
Also, as with mtn biking, there are different tires for different "disciplines". There are tires specific for Dual Sport that would be more street accommodating. Then there are true Trials tires, and then Enduro set-ups, Hard Enduro set-ups, "Woods" racing, outdoor MX, Super X and so on. Some tires can accommodate a couple different disciplines in the right conditions, but no tire can do all of them, just like in mtn bikes.
Michelin uses similar types of compounds all across the two wheel range, the MTB Gum x compound is soft and extremely sticky like high end front MX ...
My carbon frame had a warning not to clamp the frame. Fitted the starcross 6 MUD tyres to the YZ, and it gives so much confidence when railing it.
Been enjoying the channel, Thanks.
Saddles and support is a huge piece of knowledge I don’t have the experience in, have arthritis (RA) In my hips. Support and comfort I would like to understand more about the options, this was really helpful to start, and see what my local bike shop offer 👍
I'd go to a fitter and have your saddle checked out, mine was 20mm too wide and the wrong shape which was causing saddle sores, pain in the perineum and hips.. A narrower saddle with cut out and a slightly different shape stopped this because my sit bones were in the correct place.
Ive always had aluminium frames and clamp on the top tube, you only need to tighten it lightly just to hold it in place. Ive never understood why you would clamp it on the seat post as i would have thought it places alot of stress around the seat tube area, especially with carbon. frames.
No where near as much stress as the rider sat on it! It's totally fine... In fact best to clamp via the post... Workstands are all designed for that
Long time bike mechanic here: Idk if I would advise the general public to clamp their bikes on the frame. Pretty sure many less experienced riders with cheaper workstands will just clamp the frame tight to the point of over-compression and damage the frame. As long as the dropper post is fully extended, it should be safe to clamp it. If you’re not sure, you can also clamp directly to the outer shell of the post. But I have seen so many people who broke their bikes by clamping them to the frame… So hard no from me.
I have always clamped to the seatpost. Much cheaper to replace if I bend it
All mechanics I’ve seen clamp the seatpost not the frame. Don’t know why they would say that
I have a couple of old rigid seatposts to work on bikes I don't usually hang them by the droppers just by principle...
I clamp my alloy frame 😮
@@THRENO82Yeah, I've only ever owned aluminum framed bikes, and just barely clamp onto the top tube at the balance point. I've tried clamping the seat post, but the bike always pivots to a weird angle unless I make the clamp superhumanly tight. I'd much rather barely clamp at the balance point of the top tube than reef the clamp on the seat post. I guess if I ever go carbon I'll have to retrain myself...
6:56 i purchased a pretty cheap "suspension" seatpost on Amazon, it's only got about 5-10mm of travel but it does help. The only thing to lookout for is the intended weight rating for the rider. Most of these seatposts are intended for heavy riders that weigh 250+ lbs. Myself as I guess a light rider coming in at 185lbs found it difficult to find a seatpost that actually had any kind of give when riding. I'm actually planning on overhauling my cheap suspension seatpost later today to hopefully help it get a little smoother. Wish me luck, hopefully I don't end up with a tension loaded spring being shot into my face.
Another consideration for swapping out wheel sets is, how well are your pads bedded into the disk on the original wheel relative to the new one.
Great point!
What on earth are you on about??? It makes no difference whether or not your pads are bedded in on your original wheelset. They will require bedding in on the new disc in any case… and then when you swap back to the original you will need to bed them in again.
I ran 2 wheel sets on my old 26" 2x10 stumpy for years. Each had their own cassette and rotors and it worked absolutely fine. That said I started with a new chain and new cassettes on both wheels, and swapped between them quite often (ran 1 set in the week for riding to work, and the other set for actual MTB stuff). About to do the same thing with my new 12sp stumpy, saves trashing expensive mtb tyres riding to work and back with minimum faffing about..
I would have no qualms about swapping wheels and cassettes. And no, I don’t feel the urge to send my chain out to Lawrence Livermore Labs to confirm I’m within in bounds.
This is the wild abandon that comes with using mid grade components.
@@paulgrimshaw8334 Ha HA
Good tips about the dual wheels never thought of it like that with a cassette
I had the same idea with duel wheels but just got a second bike in the end.
Well thats another solution too!
Tire compounds make a huge difference... For hard Enduro moto they use a gummy tire which has a softer tread that transfers the torque more efficiently through an obstacle maneuver like bliping up a rock garden... I don't know if there's an MTB equivalent, but tires for observed trials are usually designed for trials. You don't have to get a trials specific tire, but it's more likely your going to slip out on a precarious obstacle because the sidewall and the compounds didn't respond to the surface in a beneficial way. You can put a grind on the rim or get bigger rotors for better braking but you can't make your tire any more sticky with out making it that way. Watching some of these emtb Enduro racers it's looking like they're going to need a similar range of options. They're really getting after it on those climbs with a much more aggressive attitude than unpowered cross country or Enduro racing.
Totally unrelated to MTBs. Semi truck tires being so much larger really illustrate how purpose specific tires behave and wear out much differently than general tires. So much so that you can use the wear patterns to identify other mechanical issues. I've changed enough of both things to appreciate how a $100 dollar tire that's purpose specific on a bicycle is probably worth it over a $20 dollar tire. I've used beach cruiser tires for trials because it was hard to find bicycl trials tires in the US. And the real thing totally changes the behavior of the bike at the back wheel. No more slipping out mid peddle kick when it's a little moist outside. 😂
I'm using 2 wheel sets on my bike and each of them has it's own cassette and brake rotors. I'm paying attention to my chain wear though and never had an issue with this set up.
Ebike specific and certified parts are mostly just a means for the industry to sell more gear. A 70kg rider on a 23kg Ebike is going to stress load the components pretty much the same as a 78kg rider on a 15kg analogue bike, particularly on descents where the motor is largely inactive. The drivetrain is the only area where you can argue the motors could produce more stress.
They’ll be higher stress on the down tube too. Two reasons for this. It is where the weight of the battery is slung. The shape has to change for an integrated battery, doing from a large diameter round or oval (conventional bike) to a flattened, highly irregular shape.
The weight of the slung battery along the down tube will add stress at where it meets the head tube and bottom bracket shell.
The material in a conventional bike frame can be designed to add stiffness and strength. It’s nigh on impossible to do that with a battery pack, which is not a stressed element and must possess the means for removal and eventual replacement.
The comparison you make in overall system weight (rider and bike) isn’t an equal one. Nor are rider weights you quote necessarily indicative in light of statistics. The average weight of a man in the US is 91.5kg. In the UK, it’s 87 kg. Denmark is 86, the Netherlands is 87. Croatia is 92. Canada is 88. Australia is 89.6 (I didn’t want to round up to 90 because it would appear then like I was warping the stats).
Not even Japan’s male population has an average weight of 70 kg. It comes in at almost 71 kg (70.7 to be precise).
Female weights are closer to 70 kg, but that’s not even the norm in most developed countries.
www.worlddata.info/average-bodyheight.php
Pro riders are a LOT lighter though.
Wasn't the question about bike storage about bike stand, not work stand.... So stress on the wheel mainly?
#askgmbntech seriously, why can't tire manufacturers make tire sizes consistent? I like to run different tire tread designs front and rear but many times (even in the same brand) the actual sizes can differ considerably. I've bought 2.4s that are more like 2.3 and 2.3s that are more like 2.5s. Why can't they just measure the tire and mark it as such?
Ooo this is a great question!
We'll try and cover this on an Ask GMBN Tech soon!
Cheers
Owen
Hello gmbn crew
I have some questions about carbon frames and shock placement
I am looking to buy a new bike and it probably will be a carbon frame
But in my shed i hang my bike on the wall with an airlock from hiplock
Will this damage a carbon frame by hanging it from the top tube ?
Also a lot bike i am looking at have the damper placed at the top tube, that wil be hard of impossible to hang like this ?
Of so you have ideas or suggestions to work around this ?
#AskGMBNTech Hey you beautiful people over at GMBN Tech, I have a question regarding tire wear. Hear me out please: I am currently running my bike on Assegai 2.5 Double Down and DHF 2.5 Double Down tires. I have used my bike in the winter in very cold weather a few times and I have noticed that the top layer is covered is short cracks. I am inclined to assume the damage is solely to the soft layer of the 3 compound and not to the double casing layers. I haven't lost any side knobs which is a clear indication to me that the tire is holding up very well. My question is, since both tires are holding pretty well and have double down construction, is it safe to continue using them for 1 more summer? The rationale behind my thinking is that bike parks ofter rent out mountain bikes to guests that have worse tire conditions than my current setup. If they are willing to continue using those tires on their bikes and continue renting them to guests where liability is much greater than someone who's riding on their own, then why shouldn't I?
Ooo good question - We'll try and cover this in a forthcoming Ask GMBN Tech soon!
Cheers
Owen
#askgmbntech - let's talk about the dark art of wheel building - is it something the 'average joe' should ever attempt? what is the minimum kit you need and what should you pay attention to?
I gave it a go during covid lockdown just for something to do. It's actually pretty easy, wheels stayed true and round until the bike got nicked earlier this year. All I had tools wise was a decent spoke key. I used the cable tie trick to true the wheel, and the stack of coins / cups trick to dish it, both of which were outlined in the Ali Clarkson video I used as a tutorial. Took me about 3h to do a complete wheel.
#askgmbntech on long climbs I get some lower back discomfort whilst sitting down. I just recently got my new bike and it’s an extra large which I’m just tall enough for ( maybe should of went for a larger ) is there any setup changes I can make to reduce this discomfort. Thanks
#AskGMBNTech I recently rebuilt my Rockshox fork thanks to the help of your videos! The service manual said to use Sram Butter on the inside of the wiper seals when putting the fork back together. Do you think this means Sram Butter would be best to use on the stanchions to pull up dirt that gets trapped under the wiper seals after a ride? Or would a silicone fork spray be better?
Regarding helmets why wouldn't you get the most protective, surely DH spec is the best due to speed and obstacle impact? Making stuff like helmets bike type specific is a bit daft because any bike can reach 45kph in certain circumstances.
It would be interesting to see how many viewers actually know what Cat their bike is and what type of trail its suitable for?
Finally does upgrading suspension improve the Cat of a bike?
I may be thinking complete BS, but I understand the helmet can work better when it is designed to withstand the type of impact; e.g. DH at speed hitting a tree would need a different rate of slow down than a regular trail rider hitting a rock, so a over-rated lid might not be suitable?
I may be thinking complete BS, but I understand the helmet should be designed for the type of impact; a fast DH hitting a tree would need a different rate of deceleration and penetratation resistance to a slower trail rider hitting a rock?
Where are those pristine and dry fire road trails you’re riding on?
I went out for a run last night and almost ran into a thunderstorm…. and the trails are basically still swamps!
😂
😂 the cassette chain not matching 😂 i have the same chain since i bought my bike 14 years ago and changed the cassette without changing the chain and still use it after 8 years no jokes on a 2×9 setup. I climb very steep hills still the chain doesn't slips. I had a brand new bike, new gears and new chains slips it happened to me on the road my foot went under the back wheel of my bike and I opened my leg
That sounds like a strong chain if it lasted you 8 years! 👏 We're sorry to hear that and hope your leg is all good now 🤙
@gmbntech yes it happened over 20 years ago. My calf caught in the gears. There was no infection and no scars left now. I was lucky. Thanks for asking 🙂
#askgmbntech Is the maximum user weight rating on bikes something to go by? Is it mostly tested on the frame or the suspension components? Would upgrading suspension from stock to something stiffer, say 34mm to 38mm raise the max user weight? Thanks
Great question - we'll try and answer this on forthcoming Ask GMBN Tech!
Cheers
Owen
@OwenBikeNerd for reference I just bought an ebike from Cube. Mine is rated for 137kg with fox 34 rhythm forks whereas my wife's team action 140 is rated for 150kg with kashima suspension around. Same frames, same brakes, same drive train and same (ish) 29er wheels...
If I went kashima 38 would the bike be capable of more weight..
You probably understood me but reference always helps... right? Thanks Owen
ASTM. I believe is the standards acronym
American Society for Testing and Materials
#askgmbntech what’s the safety difference between a dh certified lightweight enduro full face and a standard dh “full fat” full face helmet? Are they equally as safe specifically when it comes to bike park riding?
These questions are getting really bad. 😂
They don't always get it right. That's even funnier to me 😂
I love this show 😄
Or just put new casset on the new wheel and change the chains every time
#askgmbntech
Why is it called "crankset" and not just cranks. Because BB and chainrings are individual parts I suppose.
#AskGMBNTech
Hey, I have an old Dirtjumper where i upgraded the crankset to a shimano 12x. I also have an 12x Chain… Can this fit on a single speed cog, or can i get a 12x single speed cog?
#AskGMBNTech?
#askgmbntech Hello gmbn crew
I have some questions about carbon frames and shock placement
I am looking to buy a new bike and it probably will be a carbon frame
But in my shed i hang my bike on the wall with an airlock from hiplock
Will this damage a carbon frame by hanging it from the top tube ?
Also a lot bike i am looking at have the damper placed at the top tube, that wil be hard of impossible to hang like this ?
Of so you have ideas or suggestions to work around this ?
Ebike certified is all a load of marketing bull. For example I have friends that ride ebikes and their total weight on the bike is 75-80kg. I'm 127kg with my bike and gear and I ride normal components with no issues. Suddenly you have flyweights buying all this "ebike certified" crap when my physical frame and riding style would exert far more stresses onto the bike than any small motor or battery with a 40kg lighter rider. Im 45kg heavier than them and dont need "heavy person certified" parts.
They have all lapped up the "ebike certified" crap and loaded their bike with parts that are the same bar a certification stamp. If I can stop an enduro bike on cheap clarks 4 piston brakes at 120kg and 57kph, someone at nearly half the weight can stop an ebike without the need for a logo on their brakes. I'm doing far higher speeds down the trails than them as well due to a skill gap so the Idea that a 75kg setup needs special components simply due to the existence of a motor is just plain bizarre from an engineering point of view.
Christs sake, I can hold my throttle on my ebike full on and hit the brakes and still lock both wheels with ease so why would I need a stamp on the product to verify that?
I think the case to completely separate the Analog, acoustic human powered biking channel and an E-bike channel has reached a critical point !!! 😳
My new cubes cat 4
It means you've given up
GB
#askgmbntech. any idea where I can get 150mm cranks for my specialized turbo levo sl gen 2, it'd be nice if i dident have to sell a kidney to buy them!
Ooo good question
We'll try and cover this on Ask GMBN Tech soon!
Cheers
Owen
Holland is a provincie in the Netherlands not a land so just the Netherlands
Hi GMBN!!
Is Christina in a mood today? She seems real irritated with her cohost!!
Sending good Vibes. Shaka bra.
Pinkbike has called they didn't agree to the wife swap episode
Anna is flustered;)
Who?
#AskGMBNTech I saw a chart from the pros closet and it showed that 54% of XC World Cup wins are riders using RockShox suspension. For the Downhill world cups 68.2% of the winners are using Fox suspension. I this is the case for these two disciplines then why aren’t riders using the more commonly winning brand? I know sponsorships happen and all but don’t the racers want every performance gain that they can get?
🧠 use it sometime. Maybe it's just about who sponsors who and the suspension manufacturer doesn't actually make much of, if any, difference
Why talk about Ebike standards here?
@embn
I skip all the parts you blab about Ebikes.
These other commenters look like Ebike riders.
11:00 referencing Ebike tires in relation to moto vs bike tires is acceptable, otherwise leave it to EMBN
many ebikes are still just mountain bikes with a kick. it was a question by a viewer asking it to gmbn, they can do what they want? why are you so upset about it? just skip ahead
Leave it to Motorcycle Monthly, they’re motorcycles, pathetic little mopeds!! 🛵
Let’s be honest. The vast majority of e-bike riders aren’t going to tackle any serious trails.
A more sensible answer is that the standards are probably oriented to ensuring the frames stand up to high rider weight. A standard bike frame is usually good for a total of 300 lbs. This includes bike, rider, and gear, so we’re probably talking about a rider weight of 260 lbs on a heavier framed bike with a few add ons, multiple full water bottles, helmet, clothing etc. That all works without a vertical drop. In situations like that, the practical limit is probably far less.
Strap on a batter, motor etc., and the bike itself might tip 40-50 lbs. plus, most e-bikes don’t have fully triangulated frames. It gets in the way of some riders’ ability to swing a leg up and over.
So introducing some kind of standard for frame strength is probably a good thing for the consumer. Hopefully, those same consumers will progressively challenge themselves by progressively turning the electric assist down as part of a structured fitness programme to shed any unnecessary weight.
Saying this as a guy who could lose 10# so rides 4+ hours a week on road and trails completely unassisted.
The question is completely relevant - as Owen pointed out, increasingly shared aftermarket products (suspension, brakes, drivetrain, wheels etc.) are labelled as 'eMTB rated' - which means they tend to be longer lasting and capable of handling the higher torque/power transmission loads that you'd get with an assisted bike. Generally speaking, eMTB 'rated' parts are going to be a similar specification as Enduro or DH components, for the same reasons.
Just the word eMTB ruined my day. Why in the world they can just stick to old trusty 100% human powered bike! If your old and can't ride, then stop! You're a liability to the trail. Im not a hater, its just not right!
anna........it's "Heather"