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TECH NEWS

Trek: Road disc brakes are a Good Thing. Sometimes.

US brand explains when it believes disc brakes are a good idea, and when they're not

Trek has produced a short video explaining the brand’s views on disc brake road bikes, reiterating that it’s the Domane that it sees as the most suitable home for discs.

Trek divides its higher level road bikes into three families: Madone, Emonda and Domane.

Madone has an emphasis on aerodynamic efficiency, the Emonda is all about light weight, and the Domane has a focus on comfort and ride quality. 

Check out our guide to Trek’s 2017 road bike range here. 

In the video – which has actually been around for a couple of weeks but we’ve been really sloooooow to share it – Trek’s Road Product Manager Anders Ahlberg says, “Disc brakes have more power and better modulation. They work better in all conditions – wet, dry, dirt, pavement; they’re just better brakes.

“Disc brakes really free us up in terms of frame design. When we don’t have a rim brake calliper sitting right on the tyre, we don’t have the frame needing to be really close to the wheel, so we have a lot more tyre clearance which means you can run bigger tyres for more comfort or traction.”

The brand sees the Domane (S 5 Disc pictured below) as the natural home for road disc brakes.

Trek Domane_S_5_Disc 2017.jpg

When we’ve spoken to Trek before, the brand has been lukewarm at most about disc brakes on bikes used for road racing, and that remains the case. 

“There definitely are some disadvantages to disc brakes – weight being one of them and aerodynamics being the second one," says  Anders Ahlberg.

For these reasons there are no disc brake versions of either the Emonda – the lightweight road bike in Trek’s range – or the Madone – the aerodynamic one. It doesn’t sound like you should hold out much hope for disc brake versions of either arriving any time soon.

www.trekbikes.com

Mat has been in cycling media since 1996, on titles including BikeRadar, Total Bike, Total Mountain Bike, What Mountain Bike and Mountain Biking UK, and he has been editor of 220 Triathlon and Cycling Plus. Mat has been road.cc technical editor for over a decade, testing bikes, fettling the latest kit, and trying out the most up-to-the-minute clothing. We send him off around the world to get all the news from launches and shows too. He has won his category in Ironman UK 70.3 and finished on the podium in both marathons he has run. Mat is a Cambridge graduate who did a post-grad in magazine journalism, and he is a winner of the Cycling Media Award for Specialist Online Writer. Now over 50, he's riding road and gravel bikes most days for fun and fitness rather than training for competitions.

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12 comments

Avatar
Fish_n_Chips | 7 years ago
0 likes

Hill climbers use rim brakes.

Downhilling use disc brakes.

Using 140mm and loving it except in crosswinds.

Avatar
andyp | 7 years ago
3 likes

Wow. Bike manufacturer in 'spend your money on our marketing guff' shocker. Who'd have thought it. Anyone would think they have profits to think about.

Avatar
Jharrison5 | 7 years ago
1 like
Avatar
rct replied to Jharrison5 | 7 years ago
0 likes

Jharrison5 wrote:

Disc brakes create more drag? http://www.slowtwitch.com/Tech/Disc_and_Rim_Brake_Aero_Drag_6073.html

 

Not exactly a valid test protocol.

Avatar
joules1975 replied to rct | 7 years ago
2 likes

rct wrote:

Jharrison5 wrote:

Disc brakes create more drag? http://www.slowtwitch.com/Tech/Disc_and_Rim_Brake_Aero_Drag_6073.html

 

Not exactly a valid test protocol.

 

it may not be the best test, but the points made tie in with other tests results - namely that disc drakes don't increase drag that much. I agree with the article that given a bit of time, the designers new freedom to design rims without braking surfaces should result in wheels that more than cancel out any drag increase caused by discs. Plus so far discs and associated hubs ha be basically bean mtb hubs, with no attention on aero considerations, so I expect rotor and hub design to change and aero drag there to also drop. Upshot? disc brake bikes will probably become as or more aero than rim brake bikes, and the improved ride comfort will reduce suspension losses meaning that overall the bikes will be faster.

Avatar
tritecommentbot replied to rct | 7 years ago
1 like

rct wrote:

Jharrison5 wrote:

Disc brakes create more drag? http://www.slowtwitch.com/Tech/Disc_and_Rim_Brake_Aero_Drag_6073.html

 

Not exactly a valid test protocol.

 

Good place to start though. Clearly basic assumptions that most of us have, myself included, need put under the microscope.

 

Anyone seen more tests like this on disc brakes? Genuinely surprised by Jharrison5's linked test.

Avatar
earth replied to tritecommentbot | 7 years ago
1 like

unconstituted wrote:

rct wrote:

Jharrison5 wrote:

Disc brakes create more drag? http://www.slowtwitch.com/Tech/Disc_and_Rim_Brake_Aero_Drag_6073.html

 

Not exactly a valid test protocol.

 

Good place to start though. Clearly basic assumptions that most of us have, myself included, need put under the microscope.

 

Anyone seen more tests like this on disc brakes? Genuinely surprised by Jharrison5's linked test.

 

There have been  few tests so far, here's one:

 

http://velonews.competitor.com/2014/12/bikes-and-tech/discs-drag-wind-tu...

Avatar
tritecommentbot replied to earth | 7 years ago
0 likes

earth wrote:

unconstituted wrote:

rct wrote:

Jharrison5 wrote:

Disc brakes create more drag? http://www.slowtwitch.com/Tech/Disc_and_Rim_Brake_Aero_Drag_6073.html

 

Not exactly a valid test protocol.

 

Good place to start though. Clearly basic assumptions that most of us have, myself included, need put under the microscope.

 

Anyone seen more tests like this on disc brakes? Genuinely surprised by Jharrison5's linked test.

 

There have been  few tests so far, here's one:

 

http://velonews.competitor.com/2014/12/bikes-and-tech/discs-drag-wind-tu...

 

Interesting, 1 to 3 watts at most yaw angles, which is probably closeable over time. But at extreme yaw -20 or so, then it's up to as much as 8 watts. Ouch.

 

How did that test above with Cannondale get such different results. Must be something to do with the setup.

Avatar
Walo replied to Jharrison5 | 7 years ago
0 likes

Disc brakes create more drag? 

It may not be relevant to us mortals, but it is surely relevant for the pros in a sprint or in TT events.

Avatar
Bahrd replied to Walo | 7 years ago
1 like

Walo wrote:

Jharrison5 wrote:

Disc brakes create more drag? 

It may not be relevant to us mortals, but it is surely relevant for the pros in a sprint or in TT events.

I wonder to what extent all these single Watt/second improvements measured at a 40km distance are a gimmick and a placebo effect? The last P-R was won on a bike which was not "P-R optimized" - for example...

PS
Specialized would probably argue with Trek about aerodynamics... And it would be interesting to see the comparison between Venge Disc and Madone.

Avatar
Stef Marazzi | 7 years ago
2 likes

That's at least one sale they will be losing to Cannondale then!

Avatar
OnTheRopes replied to Stef Marazzi | 7 years ago
8 likes

cyclesteffer wrote:

That's at least one sale they will be losing to Cannondale then!

and one sale they will be gaining!

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