Please don’t make this a rim vs disc bloodfest. Stage 17 won with rim brake

[tomato]

Proof

[The drag data represents that both road bikes and tri bikes have increased drag with the use of disc brakes with products currently available on the market.

Use your eyes better or buy glasses.

The article is 8 years old, and used a hodgepodge of equipment, including a bizarre frame that can use both rim and disc brakes.

• Culprit believe that disc brakes can be designed to be more aerodynamically efficient than they are at present.

• Culprit also believe that manufacturers will be able to improve the aerodynamic efficiency of currently available disc brake hubs and rims.

[cveks]

You have link here so read

The drag data represents that both road bikes and tri bikes have increased drag with the use of disc brakes with products currently available on the market.

https://road.cc/content/feature/83327-d ... -more-aero

With products currently available on the market, says an article from eight years ago

Nothing changed in recent years. They still did not invented discs which are more aero than rim brakes.

Also GCN says their test in wind tunnel proved that rim brake bike is more aero. You are losing up to 16 watts if you ride disc brake bike instead rim brake bike.

Thats why Ollie ride Pinarello Dogma F12 with RIM BRAKES , and not with disc brakes

https://www.youtube.com/watch?v=SPhDQeQlzLg

They still bash rim brakes because they sponsors want them to do that. But cant deny that rim brake bikes are more aero.

What if someone say you that you can increase your FTP by 16 watts if you take rim brake bike instead disc brake bike?

Thats why disc brake major brand are hiding this information like snake hides its legs

[spartacus]

cveks I'm not sure if you are trolling? New bikes that are designed to have disc brakes have narrowed the gap versus the best of the rim brake aero bikes. In fact, I would argue that something like an SL7 is more aero than most rim brake bikes ever made except for a few. Honestly at this point I would assume it's a toss up. The weight difference maybe is undeniable though, but still, 500g/1lb of weight difference isn't very significant especially if you get some added benefit for the extra weight.

Lastly I think if you look at some of the more busy strava leaderboards, I don't think there's a correlation between ranking and brake type.

[cveks]

cveks I'm not sure if you are trolling? New bikes that are designed to have disc brakes have narrowed the gap versus the best of the rim brake aero bikes. In fact, I would argue that something like an SL7 is more aero than most rim brake bikes ever made except for a few. Honestly at this point I would assume it's a toss up. The weight difference maybe is undeniable though, but still, 500g/1lb of weight difference isn't very significant especially if you get some added benefit for the extra weight.

Lastly I think if you look at some of the more busy strava leaderboards, I don't think there's a correlation between ranking and brake type.

No mate.

GCN did test in wind tunnel with same bike and same rider. Only difference between two were brakes.

Bike used in test was Pinarello Dogma F12. That is almost best bike which industry can offer.

Thats bike which most successful team in recent years use it in pro peloton. Team Sky/Ineos.

And conclusion was that with disc brakes you lose 16 watts on 45 km/h . On 50+ even more. That is A LOT. If you ask me.

Especially in pro peloton where races are decided by slight margins.

You can find it here:

https://www.youtube.com/watch?v=SPhDQeQlzLg



I hope you believe to your own eyes?

Who's trolling now and who have facts?

[mgrl]

Also GCN says their test in wind tunnel proved that rim brake bike is more aero.

They specifically do not say that.

"This sort of difference in drag isn't that much, and is also within the realms of experimental error"
"We can't generalise with this result and say all rim brake bikes are faster"
"[Xavier Disley from Aerocoach] found they came out roughly the same, or within experimental error of each other, suggesting there wasn't any substantial difference between the two"
"It could well swing the opposite way on a different design"
"What we can say from this testing is that any difference between the rim brake and disk brake models aren't likely to be hugely significant"
- Oliver Bridgewood, in that video

Who's trolling now? You, still.

[tomato]

Also GCN says their test in wind tunnel proved that rim brake bike is more aero. You are losing up to 16 watts if you ride disc brake bike instead rim brake bike.

No, they didn't. 6 minutes into video:

"I was intrigued by the results, and I was aware of the limitations of testing just one bike, because all bikes are different. We can't generalize with this result and say all rim brake bikes are faster than all disc brake bikes because, well, they're all different bikes with different shapes. So, I reached out to Xavier (?) of Aerocoach and asked if he tested any disc brake bikes versus rim brake bikes himself, and he said that he had. He tested a Scott Foil that was set up identically, both rim brake and disc brake, and the results he found when testing them around the velodrome were that they came out roughly the same, or within experimental error of each other, suggesting that there wasn't really any substantial aerodynamic difference between the two."

On edit: Sorry for repeating stuff -- I'm a slow typist.

[cveks]

Weight difference between two bikes same gear - one is rim brake other is disc brake version.

Canyon Ultimate CF SL 8 = 7.02kg
Canyon Ultimate CF SL 8 disk = 7.57kg

weight difference 550 grams between rim brake and disc brake version of same bike.

Thats like almost difference between Dura Ace and Tiagra.

Facts are here.

[cveks]

Also GCN says their test in wind tunnel proved that rim brake bike is more aero.

They specifically do not say that.

"This sort of difference in drag isn't that much, and is also within the realms of experimental error"
"We can't generalise with this result and say all rim brake bikes are faster"
"[Xavier Disley from Aerocoach] found they came out roughly the same, or within experimental error of each other, suggesting there wasn't any substantial difference between the two"
"It could well swing the opposite way on a different design"
"What we can say from this testing is that any difference between the rim brake and disk brake models aren't likely to be hugely significant"
- Oliver Bridgewood, in that video

Who's trolling now? You, still.

16 watts on 45 kmh is not much?

Maybe for you , maybe your FTP is 1000 watts. But mine is much much lower so for me its a lot

And in pro peloton 16 watts is insane difference . Thats why nobody YET won grand tour on disc brakes only.

[cveks]

13 watts difference between rim brake and disc brake bike at 35 km/h an hour is massive! Everyone who thinks otherwise is out of their mind. Using any wattage estimator you can find that you need about 200-250W (depending on weight, bike, position etc.) to maintain 35 km/h on a completely flat and well maintained road. Thus, 13 Watts is more than 5% of the power you need to output! And honestly, on a real course the difference will be even bigger! On slight down gradients and/or headwinds the aerodynamics get more important & uphills you have the weight advantage as well. To conclude in a real live scenario at 250 watts the difference is at least 5% or put in other words instead of producing 250W you only need to produce 237W (& if you ever used a power meter or Zwift you know that this is very significant).

Difference is even bigger if we know that some rim brake bikes have hidden rim brakes behind fork eg. so they are yet more aero than bikes with regular road rim brakes.

[TobinHatesYou]

Come to California cveks. I'll race you on my 8kg Madone SLR Disc (or my 6.4kg Emonda SLR Disc.) Any segment length, uphill, downhill, whatever you like.

[tomato]

Yawn. You need a new schtick -- this one is boring.

[spartacus]

Weight difference between two bikes same gear - one is rim brake other is disc brake version.

Canyon Ultimate CF SL 8 = 7.02kg
Canyon Ultimate CF SL 8 disk = 7.57kg

weight difference 550 grams between rim brake and disc brake version of same bike.

Thats like almost difference between Dura Ace and Tiagra.

Facts are here.

Disc brakes are heavier but when you do the math it doesn't save that much time. Sure technically it could be a few seconds on a long climb. But in this case it's not completely one sided since disc brakes offer the advantage of lighter lever feel and outright more powerful braking, not to mention vastly superior braking in the wet. Even if the different comes down to comfort and placebo effect and the brakes don't make you faster, they just feel nicer to ride with and that's worth it for some people.

The second thing is for better or worse how light you can get the bike really comes down to $$$. If cost is an object then yes I agree that a rim brake bike is a better value.

That said when you look at actual race results, there are plenty of 17lb disc brake bikes out there doing just fine. If every scenario called for a weight weenie rim brake bike there would be more people doing it - but it turns out aero is the most important thing with weight and brakes as distant 2nd and 3rd factors.

Anyway that's just what I think. No need to keep repeating myself after this

[mgrl]

Weight difference between two bikes same gear - one is rim brake other is disc brake version. [...]

weight difference 550 grams between rim brake and disc brake version of same bike.

A bike designed for rim brakes which then needs to be retrofitted to disc is going to have a chunk of extra weight, for sure. This generation of the Ultimate has been around for 6 years. The difference between the SL6 disc and SL6 rim, on the other hand, was more like 200g. The difference between the new Dogma F's even less, as noted below.

16 watts on 45 kmh is not much?

Maybe for you

It may surprise you to learn that I am not Ollie Bridgewood, the person who said those things in the video you linked.

In addition, the F12 isn't the newest Dogma. Pinarello claim that the Dogma F is more aerodynamic in the disc brake version than the rim brake version, and the difference in claimed frame weight is only 5g between rim and disc.

[spartacus]

Come to California cveks. I'll race you on my 8kg Madone SLR Disc (or my 6.4kg Emonda SLR Disc.) Any segment length, uphill, downhill, whatever you like.

But you're gonna lose 13 watts to him because of your brakes how will you keep up?

[cveks]

Weight difference between two bikes same gear - one is rim brake other is disc brake version. [...]

weight difference 550 grams between rim brake and disc brake version of same bike.

A bike designed for rim brakes which then needs to be retrofitted to disc is going to have a chunk of extra weight, for sure. This generation of the Ultimate has been around for 6 years. The difference between the SL6 disc and SL6 rim, on the other hand, was more like 200g. The difference between the new Dogma F's even less, as noted below.

16 watts on 45 kmh is not much?

Maybe for you

It may surprise you to learn that I am not Ollie Bridgewood, the person who said those things in the video you linked.

In addition, the F12 isn't the newest Dogma. Pinarello claim that the Dogma F is more aerodynamic in the disc brake version than the rim brake version, and the difference in claimed frame weight is only 5g between rim and disc.

I dont believe to any claim until I dont see wind tunnel independent test.

Also bike brands compare always new bike with same type of old bike eg. new disc brake bike with old disc brake bike.

Reason is simple - they want to convince us to trash our old bike and spend lot of money on new one.

Claim is claim and real test is real test.

And as I can see - false marketing works great on some ppl. Not me. I believe in numbers. Not claims.