alto's carbon clincher shootout test

[ergott]

The brake pad selection must be controlled in order to accurately compare composite structures without introducing rogue variables. For example, the Enve rim may have gone 8 minutes with an Enve pad. We could then test a cheap eBay rim that comes with a cork pad, and it could run 9 minutes. Does this mean that the eBay rim has a better composites structure and resin? It's impossible to know. We would love to run the test again with brand specific pads in order to compare the results, so if anyone has another 9 rims to send us we will be happy to do it!

Rim and pad combinations were designed to work together as a system. It wouldn't be hard for us to understand the results. If the cheap ebay rim lasts 9 minutes and brakes just as well as the Enve they yes, then they would have a better braking system between rim and pad compound. Let us see that information and make the educated choice. Using pads that void the warranty on some of those rims is not useful.

It's surprising that there's not enough emphasis on that issue of pad glazing. That's a real concern in the real world. If controlling temperature is the result of pad glazing then I'll pass. I'd rather have positive braking performance with repeatable results.

As already stated over and over, a proper test would have been repeated stops or at the very least, repeated cycles of bringing down speed to simulate rider on a hairpin descent. It's not hard to look at the kinds of courses that people kill their carbon clinchers on and repeat those circumstances in the lab. That's why everyone is mentioning the Enve test protocol. It better simulates real world conditions.

If there's some magical resin composite combination that's so much better than everything out there, well that's great. You will corner the market and obliterate the competition with that sort of performance difference. I'd love for that to be the case but understanding material properties as much as I do (no expert) I doubt it. I remember when Lew had it all figured out with their Boron rims. They were brittle pieces of junk and didn't last more than a couple months of sales. I'm not saying that's the case here, but engineers tend to be too narrowly focused on one aspect of design and then something else pops up as an issue.

More testing and real world feedback needs to be done to prove this is the case. If you indeed have a winner on your hands it's only a matter of time. The skeptics will be silenced.

[BobbySweeting]

When a brand markets their pad/rim combination as a "system," what do you interpret that as? It's a mechanical system, not a chemical one, so there is no reaction taking place between the pad and the rim. So this means that it is simply friction converting energy to heat. A rim will be made with a resin that has specific glass temperature properties, and then a pad will be assigned to it that has a low enough coefficient of friction so as to not heat the rim passed the resin Tg. This is the "system" you are referring to, nothing more.

This means that an accurate comparison of rims must use all of the same pads, and it can be any pad! If every rim used an Enve pad, that would work just as well and the results would be the same. The test may just take a bit longer to run.

As we mentioned in the disclaimer, we were not trying to emulate Enve's internal test or see how anyone's rims would do with their brand specific pads, we were just trying to get an apples-to-apples comparison of composite quality, and that's what we accomplished. Our internal test is an interval one that includes rest periods so that we can see how our own rim will heat and cool in real world situations, but it's an entirely different protocol.

You're absolutely right, time will convince the naysayers of our rim quality. We try to be as open as possible with information and testing to prove that it isn't marketing, but there will be some people who are never satisfied. That's ok! We are only 3 years old but we have some pretty great engineers, two design patents, completely proprietary manufacturing, and zero recalls to date. That's a challenge for any brand, and our track record of performance and safety will certainly speak for itself.

[Leviathan]

Look, imho you should be applauded for trying to establish some law and order in the wild Wild West of carbon clinchers, and more So for posting her. However, I take issue with the protocol as all you are effectively measuring is how good the friction is between a given brake block and all rims when you hang 7kg off it. To put it another way, your rims may not heat up as much as the competition as the rims simply aren’t braking as much. We’d need to know how much power (for which amps from the motor may be a good proxy) is needed to keep the rims spinning at 20km/hr. Right now all you were measuring was at what temp the rims fail (for which there are better tests), and how they delaminate in one instance (some looks really scary but how sure are you that this is indicative of the norm for a given model). I’m sorry to piss on your fireworks, but right now I’m not sure the testing is anything more than great clickbate. Clickbait

[Imaking20]

When a brand markets their pad/rim combination as a "system," what do you interpret that as? It's a mechanical system, not a chemical one, so there is no reaction taking place between the pad and the rim. So this means that it is simply friction converting energy to heat. A rim will be made with a resin that has specific glass temperature properties, and then a pad will be assigned to it that has a low enough coefficient of friction so as to not heat the rim passed the resin Tg. This is the "system" you are referring to, nothing more.

This means that an accurate comparison of rims must use all of the same pads, and it can be any pad! If every rim used an Enve pad, that would work just as well and the results would be the same. The test may just take a bit longer to run.

As we mentioned in the disclaimer, we were not trying to emulate Enve's internal test or see how anyone's rims would do with their brand specific pads, we were just trying to get an apples-to-apples comparison of composite quality, and that's what we accomplished. Our internal test is an interval one that includes rest periods so that we can see how our own rim will heat and cool in real world situations, but it's an entirely different protocol.

You're absolutely right, time will convince the naysayers of our rim quality. We try to be as open as possible with information and testing to prove that it isn't marketing, but there will be some people who are never satisfied. That's ok! We are only 3 years old but we have some pretty great engineers, two design patents, completely proprietary manufacturing, and zero recalls to date. That's a challenge for any brand, and our track record of performance and safety will certainly speak for itself.

This doesn't read like someone who's actually gone out and ridden several different wheels with several different pads.

I'd be more interested in stopping distances with the same force than how long it takes to blow up the rim. Not that I'm interested in carbon clinchers, but I do need to do hard stops on carbon - I have never needed to drag my brakes for even a minute. And having ridden nearly every wheel in your test, my experience with braking power is almost the inverse of your results.

Also, your confidence is great - but zero recalls on a wheel I've never heard of, let alone seen in the wild, doesn't really seem statistically significant.

[TobinHatesYou]

Look, imho you should be applauded for trying to establish some law and order in the wild Wild West of carbon clinchers, and more So for posting her. However, I take issue with the protocol as all you are effectively measuring is how good the friction is between a given brake block and all rims when you hang 7kg off it. To put it another way, your rims may not heat up as much as the competition as the rims simply aren’t braking as much. We’d need to know how much power (for which amps from the motor may be a good proxy) is needed to keep the rims spinning at 20km/hr. Right now all you were measuring was at what temp the rims fail (for which there are better tests), and how they delaminate in one instance (some looks really scary but how sure are you that this is indicative of the norm for a given model). I’m sorry to piss on your fireworks, but right now I’m not sure the testing is anything more than great clickbate. Clickbait

How about watching the entire video before you cry foul? After they pass the 7lb test, they run the 9lb test and the wheel spins at about the same RPM as the best examples in the 7lb test. The rim still doesn’t ail after 20 minutes.

[TobinHatesYou]

I'd be more interested in stopping distances with the same force than how long it takes to blow up the rim. Not that I'm interested in carbon clinchers, but I do need to do hard stops on carbon - I have never needed to drag my brakes for even a minute. And having ridden nearly every wheel in your test, my experience with braking power is almost the inverse of your results.

Anecdotes are not data. Also I can safely say that I live on a road where most people would be effectively dragging their brakes for a minute or pulsing them in a way that heat buildup is still a problem. I live on a 15-16%, windy residential street with lots of driveways that covers 400ft of elevation change.

Also are you denying any of the thousands of personal stories about delaminated or exploded rim-brake carbon clinchers?

[Leviathan]

Look, imho you should be applauded for trying to establish some law and order in the wild Wild West of carbon clinchers, and more So for posting her. However, I take issue with the protocol as all you are effectively measuring is how good the friction is between a given brake block and all rims when you hang 7kg off it. To put it another way, your rims may not heat up as much as the competition as the rims simply aren’t braking as much. We’d need to know how much power (for which amps from the motor may be a good proxy) is needed to keep the rims spinning at 20km/hr. Right now all you were measuring was at what temp the rims fail (for which there are better tests), and how they delaminate in one instance (some looks really scary but how sure are you that this is indicative of the norm for a given model). I’m sorry to piss on your fireworks, but right now I’m not sure the testing is anything more than great clickbate. Clickbait

How about watching the entire video before you cry foul? After they pass the 7lb test, they run the 9lb test and the wheel spins at about the same RPM as the best examples in the 7lb test. The rim still doesn’t ail after 20 minutes.

Sorry but Im not sure how this negates the point that without knowing what the relative stopping forces are youre just working out which brake and rim combination heats faster, independent of how big a weight? BUt perhaps Ive misunderstood how a bigger weight changes the dynamic variables at play.

[TobinHatesYou]

Sorry but Im not sure how this negates the point that without knowing what the relative stopping forces are youre just working out which brake and rim combination heats faster, independent of how big a weight? BUt perhaps Ive misunderstood how a bigger weight changes the dynamic variables at play.

You’re putting a static 1200W into spinning a wheel. Your brake is slowing the wheel down to 19.5mph. There’s nothing relative about the stopping distance or the amount of heat being generated. In the 9lb test, the Alto isn’t subject to less heat, it is merely conducting it better. Understand now?

[wingguy]

Anecdotes are not data. Also I can safely say that I live on a road where most people would be effectively dragging their brakes for a minute or pulsing them in a way that heat buildup is still a problem. I live on a 15-16%, windy residential street with lots of driveways that covers 400ft of elevation change.

Heat buildup on a 400ft descent is not a problem

[Imaking20]

I'd be more interested in stopping distances with the same force than how long it takes to blow up the rim. Not that I'm interested in carbon clinchers, but I do need to do hard stops on carbon - I have never needed to drag my brakes for even a minute. And having ridden nearly every wheel in your test, my experience with braking power is almost the inverse of your results.

Anecdotes are not data. Also I can safely say that I live on a road where most people would be effectively dragging their brakes for a minute or pulsing them in a way that heat buildup is still a problem. I live on a 15-16%, windy residential street with lots of driveways that covers 400ft of elevation change.

Also are you denying any of the thousands of personal stories about delaminated or exploded rim-brake carbon clinchers?

And data using completely unrealistic inputs is also not useful.

I didn't even hint at the word "delamination". But I would love to see any evidence you have of this occurring from pulsing the brakes.

It is a little entertaining that you criticize my anecdote then respond immediately with one of your own. What percentage grade does your street have to be to result in 1200w of force that can't be stopped in less than 2 minutes?

[TobinHatesYou]

Anecdotes are not data. Also I can safely say that I live on a road where most people would be effectively dragging their brakes for a minute or pulsing them in a way that heat buildup is still a problem. I live on a 15-16%, windy residential street with lots of driveways that covers 400ft of elevation change.

Heat buildup on a 400ft descent is not a problem

It gets my disc calipers burning hot on the days I don’t feel like blitzing down the street, actually. Also we were using the example of a 1 minute interval.

[TobinHatesYou]

I'd be more interested in stopping distances with the same force than how long it takes to blow up the rim. Not that I'm interested in carbon clinchers, but I do need to do hard stops on carbon - I have never needed to drag my brakes for even a minute. And having ridden nearly every wheel in your test, my experience with braking power is almost the inverse of your results.

Anecdotes are not data. Also I can safely say that I live on a road where most people would be effectively dragging their brakes for a minute or pulsing them in a way that heat buildup is still a problem. I live on a 15-16%, windy residential street with lots of driveways that covers 400ft of elevation change.

Also are you denying any of the thousands of personal stories about delaminated or exploded rim-brake carbon clinchers?

And data using completely unrealistic inputs is also not useful.

I didn't even hint at the word "delamination". But I would love to see any evidence you have of this occurring from pulsing the brakes.

It is a little entertaining that you criticize my anecdote then respond immediately with one of your own. What percentage grade does your street have to be to result in 1200w of force that can't be stopped in less than 2 minutes?

I’m not disputing actual measured data with my anecdote, unlike you.

Also amplifying parameters is fine in a vacuum. As long as heat in is greater than heat out, it’s only a matter of time before the same destructive result. You can choose to interpret the data how you want, but we all know rim-brake carbon clinchers are borderline unsafe on long technical descents. The exploded Knight Composites rim at Phil’s Fondo I linked earlier for example. The numerous other people stopped along the side of Deer Creek at the same fondo waiting for their rims to cool as I flew by on my disc bike...

[wingguy]

It gets my disc calipers burning hot on the days I don’t feel like blitzing down the street, actually.

1 hard stop gets disc rotors burning hot.

[Imaking20]

I'd be more interested in stopping distances with the same force than how long it takes to blow up the rim. Not that I'm interested in carbon clinchers, but I do need to do hard stops on carbon - I have never needed to drag my brakes for even a minute. And having ridden nearly every wheel in your test, my experience with braking power is almost the inverse of your results.

Anecdotes are not data. Also I can safely say that I live on a road where most people would be effectively dragging their brakes for a minute or pulsing them in a way that heat buildup is still a problem. I live on a 15-16%, windy residential street with lots of driveways that covers 400ft of elevation change.

Also are you denying any of the thousands of personal stories about delaminated or exploded rim-brake carbon clinchers?

And data using completely unrealistic inputs is also not useful.

I didn't even hint at the word "delamination". But I would love to see any evidence you have of this occurring from pulsing the brakes.

It is a little entertaining that you criticize my anecdote then respond immediately with one of your own. What percentage grade does your street have to be to result in 1200w of force that can't be stopped in less than 2 minutes?

I’m not disputing actual measured data with my anecdote, unlike you.

Also amplifying parameters is fine in a vacuum. As long as heat in is greater than heat out, it’s only a matter of time before the same destructive result. You can choose to interpret the data how you want, but we all know rim-brake carbon clinchers are borderline unsafe on long technical descents. The exploded Knight Composites rim at Phil’s Fondo I linked earlier for example. The numerous other people stopped along the side of Deer Creek at the same fondo waiting for their rims to cool as I flew by on my disc bike...

Wait, so are you for Alto or against carbon clinchers altogether? All of the sudden I'm not sure why you're arguing so much (but I am proud of you for making it down your street safely thanks to discs). I am talking about stopping power. Saying these brakes will die last doesn't not mean they will stop the fastest. That is my point. I am not "disputing actual data with anecdotes" (especially since the testing criteria is based on anecdotal numbers in the first place). If Alto has a new way to stop carbon better than anyone else - I'm interested in that. Sincerely. And it'd be bigger than just clinchers.

Then again, perhaps Alto's intent is just to market their wheels as the last to fail catastrophically for dentists with poor riding habits - instead of focusing on speed and weight like everyone else. If that's the case, I can accept it and move on.

[TobinHatesYou]

Wait, so are you for Alto or against carbon clinchers altogether? All of the sudden I'm not sure why you're arguing so much (but I am proud of you for making it down your street safely thanks to discs). I am talking about stopping power. Saying these brakes will die last doesn't not mean they will stop the fastest. That is my point. I am not "disputing actual data with anecdotes" (especially since the testing criteria is based on anecdotal numbers in the first place). If Alto has a new way to stop carbon better than anyone else - I'm interested in that. Sincerely. And it'd be bigger than just clinchers.

Then again, perhaps Alto's intent is just to market their wheels as the last to fail catastrophically for dentists with poor riding habits - instead of focusing on speed and weight like everyone else. If that's the case, I can accept it and move on.

I am for everyone making the switch to disc braking. I am also for improvements to rim-brake clinchers since people will keep buying them. I am also for transparency from the manufacturers...rim-brake carbon clinchers straddle the line between acceptable and unacceptable failure modes.

Thanks for your sarcasm, but descending a busy extremely steep and windy residential street safely would force me to stay around 20-25mph. I have the KOM at 40s (34mph) and the next fastest time is 47s. Gravity would easily accelerate me to 55+ mph, which is equivalent to a bit more energy over ~1min than in the Alto test.

Nobody is arguing that the Alto wheels will stop fastest, so grats on your strawman. What is clear from the test though is that 2lbs more brake force makes them stop in the same distance with better heat dissipation. In fact I’ll point out that at 7lbs force, the Alto rim is clearly conducting less heat than any other because the wheel is spinning faster. That’s why the second test is important and I don’t mind the results.

Alto’s intent doesn’t matter as long as their methodology is sound. It’s your interpretation of the results and objective facts that ultimately matter, not marketing.