Are Big Disc Brakes REALLY Better?
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- Опубліковано 28 вер 2024
- We know that bigger brakes can stop you faster, but what about their efficiency? We went to Girona to find out whether a bigger disc brake rotor will not only have a lower peak temperature, but also dissipate heat faster than a smaller disc brake rotor. It's time for some GCN Science!
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What did you think of the results?
You came to the same conclusions as I gave when selecting rotor size for the weight.
.....not really a scientific test.....you have to measure it permanently and you also have to know the speed, weight, energy which got transfered into heat for one ride and so on.
should try it with an alloy rim brake wheel 😉
Being a mtber and roadie id say fairly predictable, good to see some peak torque recognition tho. Yeah come on let's test some stuff to destruction, get the lathe out. Big brakes are great if you're an aggressive decender theyre always good to go - fade is a thing of the past and in 24hr races having more than enough power is a bonus with tired cold hands. If you're a bit of a panic braker tho good luck, best thing you can do is work on your spacial awareness so things don't suprize you.
The 55ish degrees across the board shows that the experiment probably isn't hard enough to show any difference between the rotors. (Although the faster heat dissapation of the 180mm is a hint at potential superior performance)
Would love to see some more experimentation on the subject :)
If in doubt, ALWAYS get the biggest.
I’ve got a 622mm disc. It’s called rim brakes 😂
@@mondoabz pmsl brilliant
@@mondoabz ... Eroding the structural strength of a rim to us as braking surface is one of the more moronic things the cycling industry has come up with. Thankfully it is going away.
Is the extra stress from a larger rotor on the fork a concern?
As long you don't use Titanium bolts you should be okay.
Love to see this explored more. I built an adapter back in the early 2000s to mount 8" rotors to my MTB as there wasn't anything available at the time and discs were so new. Ran 9" up front and 8" at the rear for literally 20 years now. Love it. Keen to see how a bigger disc works on road bikes as I find my 5" fronts lacking in stopping power to be honest.
I run a gravel bike with mountain bike brakes, using a 180mm rotor upfront and 160 in the back. No stopping issues. Sometimes too much. I love it.
You touched on the real benefit, but wasn't the focus of your test. The biggest benefit is heat recovery in a situation where you have to brake on a continuous basis (same on a car/truck). A long technical descent where you are breaking hard on and off for 10 to 20 mins would be a better test.Also at what temperature do you start to loose breaking power? You could use a lath to perform both test.
I wish they had discussed about the warping being often more prevalent on the larger rotors by comparison (usually due to just larger distance from the center axis).
My front 160mm Shimano definitely causes me considerably more grief than my rear 140mm.
Wouldn't that be down to using the front brake more?
@@SMlFFY85 how much you use the rotor, at least theoretically, shouldn't affect how much the rotor warps. It mainly warps (in the real world) because of the tight spacing along with the regular heat increase and decrease as materials expand and contract (particularly when it comes to bonded materials of different varieties like steel and aluminum). They inevitably tend to not always go back to normal dimensions (when we're talking sub-millimeter) because of these things.
From what I've read, the 140mm rotor is technically thicker by a hair than the 160mm. And since the length of the radius on the 160mm rotor is more, there's more potential for that material to get "out of true" to borrow the phrase, especially given the reduced thickness of the rotor. I'm luckily a smaller rider, so which diameter I use seems to largely be inconsequential, but I've considered running dual 140's to specifically avoid this issue. I pretty much never have rotor rub on my rear 140mm rotor when I have constant squealing and rub on my front 160mm rotor.
It would have been nice to see some of this mentioned in the video!
@@tmswfrkdid you ever try 140/140? How did it go?
@@thedownunderverse yeah it’s what I run now. I’m a lightweight rider, so weight isn’t an issue and I haven’t really experienced any fading.
So far my choice of SRAM rotors has been working without too much squealing, as long as they aren’t contaminated and have been bed in properly. I’ve also started using resin pads again, which I think can quiet things down a bit in some cases.
@@tmswfrk cheers for that! I’m 72kg and considering trying 140/140. Expensive test though
On racing tandems you need the large disc brakes to cope with the extra weight like Ollie saw on my tandem submitted to Nice/Super nice.
My rider/bike weight is 172kg and we have blued the disc’s on a mountain descent.
On our (non-racing) tandem we use either 203mm XT(R) rotors front/rear from spring to fall or 160mm (Ultegra) during winter.
What size rotors do you use?
Correct, weight and load will be affecting factors on the conversion of kinetic to thermal energy. Increased weight and higher load transfers will require the highest efficient transfer anticipation mediums.
@@gcntech 200mm front 180mm rear
Captain/Stoker combined weight 270 lbs 123 kg we used 203mm rotors and metal pads on my road racing tandem (200 milers- 500 milers) - but I would never ride disc brakes on my solo road bike.
I use 622mm brake rotors. They're made of carbon and everything.
In my cause change front disc from 160 to 180mm was perfect decision. It cost me around 20usd for disc and adapter. Also when i had in one season Giant Fastroad i changed front one from 140 to 160 and i had not regret it
I weight around 95 kilograms so it is very efficient
I am no road bike cyclist, because I am stuck in the past(xc biker) and I use my old school ht from 2003 or 2005 with xt br785 brakes with 203 up front as ac commuter. swtiched to 203mm rotor up front because I could not stand how bad discbrakes actually were. 160mm rotors glazed my brake-pads very often, even at 203 it was quite common. So I switched to sintered pads and it actually did make a difference but still not as good braking perf as old school v-brakes, especially in combination with ceramic coated rims.
My work college is still a proper xc biker and tested my bike and said it had the best brakes he ever tried, well I have to say that bikers know absolutely nothing about brakes in that case. I still consider my brakes to perform very poorly. Try a motorcycle and see how good they brake or simply a bike with v-brakes :P
to get proper disc brakes we need thicker rotors.
I switched from the supplied 140mm front disc Ultegra R8000, to the same in 160mm. I need much less force to brake equally, hence your idea of less wear is justified. Where I ride there are often stop lights on hills so coming to a complete stop from 70km/h was taxing on a 140mm front rotor, now seems to be less stressful!
12.5%
Much less force is merely a perception, your initial input of Force to the brake lever will be the same no matter what size rotor. Larger rotors can transfer & dissipate thermal energy. There is less fade with larger rotors thereby creating the perception that you need less force on the lever. After initial pull of the lever you need less Force to maintain the same braking power.
@@rider65 of course you need less force with a bigger rotor for the same braking power. its simple physics - bigger lever, less force required.
I ride a very roadbike-esque city bike (700C, no suspension, Tiagra all around) and I regularly tow my twins in a trailer. About 45kg for the whole lot (trailer and kids) switching from 140 to 160 made a significant feelable differece. At least in terms of stopping power and distance.
we’ll see bigger disparity if we were operating at the end of the rotors limitations. Within regular operating temps would be marginal gains.
But if it’s a heavier rider or a steeper descent the benefit of the larger rotors would be more apparent.
The heavier rider thing is key. I'm 85 kg and have descents nearby that are 36% grade in some switchbacks. If I could post a pic of my rear rotor that is blue/brown for an inch from where the pads touch the rotor, I would. I tend to ge really far back behind the saddle when I'm trying to make good use of both brakes descending, which is a technique you have to use when descending steep muddy terrain on a motorbike. If you don't get far back behind the seat, weight transfers to the front wheel until you're doing a "stoppie", which is no bueno. Next test, try out pads with no fins, then Shimano L05A with fins, and throw in some Absolute Black pads for giggles.
I’d love to see GCN/GTN get an electric motorcycle for the camera crew so we don’t hear the exhaust noises. 👌👍
Or the riders have to smell the fumes
I'm surprised the change in modulation between rotor size was not discussed more. It is my understanding that is a big reason for selecting one size rotor over another, since a smaller rotor has more modulation than a larger one - that's the "less input" feeling that was mentioned by Alex.
180mm might not be the best for every situation. In cyclocross, most pros (under 80 kg) use a 140mm to have better modulation and control of the grip their tires have with the ground. The same can be said for an lighter rider on the road too: a larger rotor could be harder to control and make it easier to slide out. SRAM takes this into account in their rotor recommendations chart.
From my experience you won't slide out at the front even with a 180 rotor (in the dry, with good tires), the tire always has so much grip that the bike will want to somersault if you overdo it, but not slide. In the rear though there is really no need for more than 140/160mm on a road bike because you simply can't transfer much energy there without locking the wheel.
The weight of the rider and a more controlled scenario of constant breaking would give a better result. Also using a FLIR camera would give a good insight of the heat buildup and heat disapation
You need to test some MTB 220mm rotors
I've noticed that 160 mm disc's work better than 140 mm. However a 700mm disc works better. All are aluminum. Carbon doesn't work anywhere near as good.
There's nothing on that run needs braking unless you are trying to keep below the speed limit.
I have a rotor that is about 700c--rim brakes are state of the art tech.
Rim brakes for the win.
Another silly remark by somebody who is completely uninformed. A 700c rim is not a brake rotor. You're breaking surface is limited to the breaking track not the entire wheel. There is no swept area on a spoked rim. The spokes and the Hub are unable to absorb and dissipate any energy and heat. Whereas a disc rotor it's absolutely designed to do that. And is much more efficient. Physics does not care about your opinion or your feelings the fact is that a disc rotor is far more efficient and has far more performance than any rim brake. If you understood the basics of physics then you wouldn't make such a silly statements. Again the mechanical laws of physics do not care about your opinion or your feelings Fozzie Bear. Now do us a favor and pull your thumb out
...in 1980
Agree. A rim brake is after all a disc brake that uses the rim as the rotor. A rim brake probably never gets to 54C.
@@andredegraaf1643 I love rim brake! But I am curious for this experiment!
Like rim brakes because it’s a cheaper option but I’ve noticed over the last week due to an awful lot of rain I’ve been breaking much earlier and been a lot more careful than other riders I’ve been cycling with who have disk breaks
No big deal. Seriously, how often are you descending, in the rain, under race conditions? Almost never? Then just anticipate early braking like you just described. No need to add a squealing kilo to your bike for the maybe what if moments.
I think I’m going to steal that from you. “squealing kilo” 😂 and don’t forget the additional cost of buying a disc brake equipped bike
That 180 looks sooooo good! Put on a 203!!!
When a loaded tandem could easily go 200kg, it makes sense to make larger discs for road groupsets.
I weigh a 100kg and the stopping power is very noticable for a 180mm disc. For comparison i did the test on a roadbike(140,160,180) and my downhill bike(160,180,203), both in Belgium and the alps.
Would love to see a graph of the rate of cool down for each disc size. Great video!
Being rubbish at decent and 80kg I got a heat temper blue purple 160mm rotor on my tcr and have broken cables on mechanical disc setups and sheared the friction material off the pads. The hydraulic is better but still need more stopping power.
In my opinion. Which is the most important opinion. The Only good rim brakes. Have been melted down and recycled into baked been tins. I have always had a passionate hatred of rim brakes. Even that substandard tat was the only brakes you could get. As for disc size. Both my 27.5" full sus and my 29er mountain bikes have 203mm front and 180mm rear. Both have 4 pot calipers. As my hybrid on had 32mm tyres. Not the 2.3" on the full sus and 2.6" on the hard tail. My hybrid only has 180mm front and 160 rear. With 2 pot calipers.
If only there was a way to get a larger rotor than 140, 160 or 180 on your bike OH YEAH a 622mm rotor called rim brake bike technology!
220 mm with 4 pot calipers have sufficient stopping power to rip fragile Road bike forks apart ;-)
🤘🤘 cool bike nice channel watching from Philippines
Thanks for watching!
Even as a light-ish rider, I use 160mm front and rear for two reasons.
1) easy to swap wheels between bikes by having consistent across all bikes.
2) reduced leverage. I've not got massively strong hands sue to injury. If I. Can reduce the strength needed to achieve adequate braking.
the part where this test fell short was not measuring the rear rotors. On a long decent, you tend to hold the rear.
90kg and on deeps descents with switchbacks my breaks are sometimes overheating. Would like so see the temperature for heavier riders on steep descent... guess there would be a difference in peak temperature depending on the rotor size
What about different discs and pads, eg. EBC discs and pads (instead of stock ones). Will they also help reduce the stopping distance…???
Short answer: Yes, with massive caveats.
Physics says that disc size/surface don't have anything with stopping power: F= μ x N (Amount of friction = coefficient of frictions X force pressing the object against the surface). That's why are all disc are heated to the same temp. Disc size/surface matters for cooling - bigger disc avoid overheating.
Premise wrong, conclusion (luckily) correct. :-)
Certainly for mountain and other offroad bikes I will always stay with disc brakes. There is just not substitute in my experience. I rode with rim brakes for YEARS and the first time I rode with a disc it was a revelation. The bike actually stopped in the heavy rain/mud and the front end felt more controllable. Not to mention my hands wouldn't tire after a long technical and cold/wet decent. For road it isn't as important but in the rain coming downhill on a long ride I'm sure it makes a difference.
140 front & rear on my Ritchey Outback. Looks sweet, have Klamper brakes so no issues! Well proportioned with my 10-42 cassette. I learned how to brake on a Beetle with 4 drum brakes😜
How Ollie said ,,we are talking about discbreakrouters,, in the Intro, so sweet
Yes, let’s get some glowing rotors please! Great video. I hope you had a great time in Spain!
Glad you enjoyed it!
The best braking effectiveness would be achieved by a solid rotor, but its heat dissipation efficiency would be woeful. That's why even decent automotive disks, whose weight matters a lot less, are vented.
got 240mm prototype rotors last week and can't wait to test them
"better"? At what metric?
"Small" discs have enough leverage to lock the brakes. Bigger discs can carry more heat because it has more material and can dissipate it easier by having more surface area. The same is true for car brakes: big brake kits are used to stave off brake fade not for stopping power, stock brakes are sized to be able to lock the brakes (hence why ABS is needed).
Force required at the lever and modulation. Softer levers are way better to use and allow way more control, allowing to get closer to the locking up point without crossing it.
At normal temperatures braking performance is dictated by tyres more than rotor size; if you can lock the wheel or do an endo, the rotors are big enough..... with the caveat being that of heat dissipation. If you have trouble with overheating (big rider and/or nervous descender and/or riding long fast technical descents) then bigger rotors make sense. But if you don't tend to over heat your brakes there's no need to go large. One of my buddies is 90kg when in top shape but a very capable descender so runs 140mm discs.
Happy New Year you disc-loving For Cars!!!
Do the same on a downhill MTB 😄
I would like to see a 15-20% decend with 250lb rider. I agree that for light/ moderate riders going down moderate declines, it doesn't matter. But i recently did the tripple bypass in colorado. And 20 mile 10-15% declines at 30-40 and sometimes 50mph decents scared me to death.
What would also be nice is to know how things go bad. Do the brakes fade. Do they make sounds then warp. Or do they break and bind. I mean, if you have to push them, then they will rub a little thats one thing. If they lock up at 40mph on the side of a mountain thats another story.
now I want a video where you test how much decending is required to delaminate carbon rims with rimbreaks
The secret is not to have carbon rims. Gee, d'ya think perhaps a metal layer could be bonded to carbon? Think about it...
@@stephensaines7100 It'd be better to have an actual aluminium rim with a carbon fairing (like how HED does it), but at the cost of weight.
IR thermometers are calibrated to work on a blackbody. Human skin is a good approximation. A steel rotor is not. It is reflective of IR, corrrspondingly less emissive, and specular. Which means your measurement depends, perhaps very sensitively, on the angle of measurement. This was not controlled among several other factors
You can get a much better measurement if you put some black paint on a piece of the rotor
Measuring heat with infrared sensor on a metal is VERY inaccurate. Most of the reading will be the reflected infrared emission of the surrounding enviroment and since it is even a polished material it won't even be the average of it but dependant of the angle how you hold the tool and the angle of the brake disc too.
The reason why the size of rotors doesn't really affect price is that the cost to the manufacturer is almost identical.
R&D, tooling, the time it takes for something to be produced, shipping and distribution are all costs that remain effectively the same no matter the size. The material cost does change but the final price is almost always rounded up to some X0,99 price which covers up all those differences.
There are so many different brake pad formulations with copper or alloys and fiber combinations all of which will give different breaking performance's what about all that tech please .
I have a disc(160) and rim brake bike and never really had an issue with my rim brake set-up compared to the disc brake bike. However, recently going out to Spain at Christmas and using a hired (Orbea) rim braked (105) carbon bike, I had less confidence in the brakes. Even though it was alloy rimmed with decent tyres. Granted I got mixed up with front and rear brakes early on (swapped over on bikes on the continent), I either locked up the rear too easily or didn’t feel I had enough stopping power on the steepest descents. Not sure if I was the pads or what, but my own rim brakes bike has much more modulation and control. Maybe I’m just used to the setup more. But it did make me appreciate the arguments for discs more.
The pads and rims make a huge difference, as they would on any vehicle, as they do on discs. With the right pads and rim surface, you'll get as much stopping power as discs if your calipers meet a given standard.
Can you test rim brakes with differs surfaces? Carbon, aluminum and coated aluminum like DT Swiss Oxic.
I'm old enough that I got into cycling before disc brakes were even available. Rim brake bikes are lighter. I bought my first new mountain bike with cantilever center pull rim brakes. I eventually upgraded to V-brakes. I bought my first disc brake bike back in 99'. I could feel the difference immediately. I had a friend who had cable disc, which weren't quite as powerful or as good modulation as my Hayes hydraulic ones. After going from 6 inch rotors to 8 inch rotors I could feel the brakes were so powerful enough to put me over the handlebars if I wasn't careful. With 6in rotors no mater how hard I braked I wouldn't ever go over the handlebars. I know from personal experience that bigger brake rotors really DO make a Big noticeable difference! That said, most won't agree with me but, I believe that disc brakes belong on mountain bikes and not on road bikes. I've never been interested in adding any weight or complexity to any road bike I've owned. Thank you.
I have to buy a new bike because of an international move. All the manufacturers have moved away from rim brakes to disc, especially my first choice Canyon, so now I'm moving to disc brakes for the first time. I'm really worried about the longevity of these things, especially after Peak Torque claimed that you can go through two pairs of rotors per year. That's a very high cost.
Your place in their religion is just to Buy. Not think.
@@stephensaines7100 that's not what I asked
If only there were a disc, with a lever arm the same as the radius of the wheel for maximum leverage.
I'd like to see a test on a 15% downhill with sharp turns where you have to repeatedly brake hard with little time for brakes to cool. Doesn't even need to be a heavy rider but that would make it a tougher test. I get brake fade with a front 180 mm ice rotor on my local hill.
Ha ha hello Larry I know you’re describing a local mountain (Baldy ski lifts) to us but that’s not what the rest world has available to them. We are spoiled in Southern California with our mountains. If they performed the test as you outlined there would be barely 5% of the cycling population that would encounter that scenario
@@SeeYouUpTheRoad haha, I was actually thinking of Crownview Dr in Palos Verdes, but Baldy descent from the ski lift parking lot is nasty, too. It's amazing how quickly you pick up speed before hitting the brakes at Mankar Flat.
@@larrylem3582 I’ll have to come up and climb that one sounds fun!
Statements & Questions... Statements: 1. Larger discs provide more leverage, more surface area for heat dissipation, AND, more mass for Heat Soak... 2. Added leverage requires less force on the brake lever for the same amount of brake braking power(as a smaller rotor), OR more brake power for the same amount of lever force(with a larger rotor)... Questions: 1. Is using brake discs with cooling fins only a fair test? How would non finned discs perform? >.> P.S. What's that bulge on 'Not Ollie's'(I don't know his name)down tube? (I have one on MY bike - but's it's custom\I put it there) O.O & rim brakes are dead to me as their performance fades when riding in the wet(not that I condone riding in the wet - lol)...
I've got a gravel bike with 160mm rotors and an xc hard tail that's basically set up as a slightly more hardy gravel bike up with 180mm rotors and fast tires.
Descending on the 180 rotors feels so much better. The 160s start to noticeably fade on high gradients and I have to be mindful of how much I'm riding them. Both are using shimano resin pads, and both rotors are shimano rotors.
I'm 88kg. if I was 60kg I'm sure the 160s would feel fine :D
Swapped from resin to metallic pads while keeping the 160mm diameter, the difference is like night and day!
I've always wanted a slightly bigger disc.. and thicker.. to prevent flex
So disk rotors that are larger require less effort to create the same braking effect. Agreed, that's just physics. However, a rim brake is just a very big disk, so following the same physics principal, a rim brake requires less effort to produce the same braking effect. Let's see a test of that if you're brave enpugh to upset all the manufacturers ;-)
Interesting experiment but no mention of brake pad area. Brakes convert kinetic energy to heat and noise via friction. The pad area has not changed regardless of rotor diameter, so assuming the rider mass and velocity was consistent between tests, I don’t expect any differences in rotor temperature. Increasing diameter will dissipate heat quicker and change braking force/feel.
Cool Glasses Alex
I think the real question is which would prefer to have when you want/need to stop. We use 203 mm rotors front and rear on our tandem (160 kilo team) These work really well wet or dry. They are mechanical. I have noticed especially when in Europe in the Mountains that the pads wear quite quickly. Let's see the test in the real world with heavier riders.
700c rotor crew - Rim brakes for the win in 23.
Drum brakes rule 🤘
Lol at the opening scene
What I’ve heard most is that “it’s how you use it, that matters.”
The temperature going down rapidly isn't because of heat dissipation to the air, it's going into the brake disk. When you brake the outer surface gets hot, then over time that heat is conducted into the rest of the disk. Maybe a better temperature test would be 30 or 60 seconds after breaking when the temp has averaged through the material.
You do love spanish weather
As someone who still owns three rim brake bikes, I wouldn't want more braking power than the already sensitive 160mm hydraulic options. I would expect more modulation with brakes that require more lever pressure, and if we already have the ability to lock up a wheel with one finger, why would we want easier braking? although the temperature theory didn't pan out, the 160's should last 14% longer.
I enjoy disc brakes, but there is something so simple about caliper rim brakes on a road bike. I built a bike with ceramic rim material with matching brake pads had better braking performance than any disc brake.
As a 110KG mountain biker, the larger rotors really have made a huge difference for me. That being said, would love to see a 203 (or dare someone find a way to put a 220) on one of these bikes!
220 mm would probably tear the fragile road bike fork apart ;-)
What temperature will disc brakes fail?
You get some fading if it's above 300° C, but it still works then. The first thing which happens is the pads will burn away, but there's almost no chance to achieve this on a bike (it was once tested on a lathe)
Happy New Year!!!
What would be interesting is to see the difference in speed for different rotors. Theoretically, you can brake later before going into a turn.
Interesting, but almost impossible to conduct as a controlled experiment. There are too many other factors -- human factors -- to conclude anything that's not already obvious.
i'm a 95kg rider. I don't feel like 160mm rotors give me anywhere near enough braking power. i felt safer with rim brakes
you guys should do a bike check of your camera motos, that would be really interesting.
Size matters in everything. Basic knowledge
Don't know about the disc brake size experiment, but I do know that Ollie looks much more comfortable (physically and visually), wearing kit that's sized correctly for him. (in re Amazon cheap kit video)
Do on a dynamometer with a thermal camera, not with the temperature gun.
Makes sense that you’d have the same temps at the end as the same amount of kinetic energy is getting transfer thermal energy. As for shorter stopping, it’s incorrect to say that the larger rotors stop faster and have more leverage. See this engineering video ua-cam.com/video/CyH5xOcsXxs/v-deo.html Larger rotors will give you more braking performance over repeated heavy use and reduce the risk of exceeding the brake system
Ah the peak torque bbc
Big rotors should be standard, I am a frankly short fat bicyclist person, Manufacturers are sucked into the black hole that is lightweight and sized for skinny tall or tallish blokes , because that's what pros use so that's what flies off the shelves. its like XXL cycle clothing is about L for any other garment. (where did I leave my heavy duty soap box). Harumph.
Yes please……. Cook those rotors (in the name of science, obviously 🤣)
Non-issue. From full chat to stopped, you're not getting anywhere near the temperature at which the rotors would warp. Maybe if you weren't so skinny... 😁
Also yes please. Throw it on a lathe.
It’s not all about size it’s how you use it
160 front and rear for gravel, 160 front and 140 rear for alpine roads (perfect for my 68kgs)
That 700c disc the tires are mounted on
Will manufacturers have to beef up the forks to handle the greater peak strains of the 180s?
Yes, even MTB forks have limits here. The XCR 32 (32 mm stanchions) for example has a limit of 180 mm, while the XCR 34 (34 mm stanchions) is allowed for 203 mm rotors
How many scripts did Ollie pitch to be able to use his heat gun again?
I’m 88kgs and run 160F/140R on my road bike. On my MTB I run 203 F & R.
Yea let's blow up some ROTORS
#askgcntech. Hey guys (and Manon), do saddles “wear out”? I’ve had the same one on my bike for 5 years/30k+ km, but it looks the same as ever. I’m spending a lot of time this winter on the trainer and I’m finding it quite uncomfortable. Is it the style of riding I’m doing (ie trainer trekking v out on the road), or do I need to spend some money on a new one?
Here is the experiment you should be doing. Disc brake vs rim brake with alloy wheels with your heat gun.
Measure the temperature of the alloy rim when you come to a stop just like you did on the rotor. Time the cool down time from hottest to a baseline. Just as a curiosity time the run. On a sunny day because the mass population of the world wouldn’t go down a mountain in the rain.
Alloy wheels not carbon wheels because we all know they brake better but more importantly they represent the largest segment of the viewing and riding population.
Ahhhh you're one of those!! I'm assuming you hate tubeless and electronic shifting too 😂😂.
Discs are just better dude. I commute all year round. I wouldn't swap hydraulic for anything. Not to mention the only maintenance I've had to do in 5000 miles is one set of pads. Which took about 3 minutes. Less fade, better in all weather, less maintenance, more modulation and probably cheaper in the long run given maintenance is almost non existent and it doesn't destroy your rims.
@@jesmondo5785 absolutely think tubeless sucks. I made a video on my channel with 25 reasons why tubeless road sucks you should watch it. I’ve been trying to make tubeless work for 14 years and ridden over 100,000 miles on it - it sucks! Disc brakes suck too! Di2 I had it back from 2009-2018. It’s great but unnecessary. And now with the release of 105 Di2 it has put it out of reach for the average rider.
Incorrect assumption of cheaper long term. Here in my shop I am replacing disc brake pads every 2-3 months for my real riders and rotors every other brake pad swap. That will cost you more than an alloy set of wheels WHICH I’ve never had to replace. I ride at least 10,000 miles per year. I climb AND descend 1,000,000 feet per year I’ve never had to replace worn alloy wheels that is total bullshit “dude”
Do the math brake pads $20-$40 for each set of pads. Rotors $50-$90 for each rotor over and over and over again for the life of your bike - rim brake pads $10 and they last years and rims don’t wear out like people like to exaggerate that they do.
But even if wheels wore out look at the escalation of the arms race between these component manufactures every 3-4 years we have a new drivetrain speed - 10, 11, 12 and 13 speed drivetrain speeds. You need new wheels anyway. Come on your argument is moot in every possible way. Additionally, you don’t ride much so you don’t have enough real world experience to embarrass yourself Worldwide in the UA-cam world.
@@jesmondo5785 keep in mind I own a shop I see thousands of bikes per year and many are my repeat customers so I see all the issues my real riders will have throughout the year (tubeless, disc brakes) - your sample size is n=1.
@@SeeYouUpTheRoad been running tubeless from 32mm to 44mm for well over 50k miles. Literally 0 issues. Sooo yeah... You don't really have to try and make it work. It just works 😂. Maybe hire a mechanic for your tubeless setups 😂
So these 10k+ riders take their bikes to you to have rotors and pads changed? I don't think so 😂😂 it's a 5 minute job for a monkey. Ultegra level pads are literally £10 and have lasted me I do at least 100 miles a week. I'd say that's some pretty heavy mileage. That's also on rough as fuck terrain for about 50% as i live in the sticks.
I've cycled, road, trail & dh since I was 12. I'm 30 now. I have plenty of experience thank you.
I've ruined multiple sets of rims via rim brakes. Rotors last forever, I'd guess at least 10k on my current mileage. The reality is it's mainly front, rotors are £40.
There's a reason mtb have used discs and tubeless for years. Because or works.
@@jesmondo5785 ahhh see you ride clown car tires on your bike 32mm and 44mm 🤡
So years of experience from the auto/motorbike racing industry does not apply to bicycles?
Rim what? So, on my MTB I have 203mm Hope rotors and Hope E4 4-pot brakes. They're incredibly powerful. So powerful that they'll easily lock either wheel with one finger. However, my road bike has bigger wheels, goes faster and has more consistent traction but small feeble brakes. Why??? Surely the road racing bike should have massive brakes and the MTB that is traction-limited should have smaller brakes?
A big rotor starts at 203mm. Noticably less heat/glazing.
I'm no engineer, but doesn't it mostly have to do with thermal mass more so than leverage? You're converting inertia into heat, so more rotor mass = the rotors ability to retain heat longer? Idk I've never fully understood brakes.
That's cool. I've had an idea 💡. Imagine a 700c size rota, massive. You could integrate it onto the rim for better areo gain. With the mechanical advantage of a large Rim disc you could probably get away with using rubber pads on a caliper. 😂😂😂
would like to see rotor being dragged to the max temperature (preferably until red hot) and then release.
I thought smutty innuendo died out in the 70s. It wasn’t funny then and is bordering on offensive these days. In a sport that needs to increase its appeal to all riders this is poor. Their are many fit larger riders that are over 100kg riding (will hoy is one) but this decent technical argument is lost with the inclusion of out of date clichés.