rear brake under chainstay pros and cons in general - scott foil rc specifically

Discuss light weight issues concerning road bikes & parts.
octave
Posts: 99
Joined: Sun Jan 15, 2017 8:47 pm

by octave

hi everyone,

i asked this question in the "Scott Foil '16" thread but it didn't get much traction. thus, i figured i would start a thread.

i am interested to know people's experience with under the chainstay mounted brakes. i worked on a 2014 trek madone 5.2 that had them-- bontrager speed stop or something? -- and it was a bit annoying but once i got it set up it was pretty powerful. that being said i did not spend more than a test ride on it to make sure it worked. i now have the chance to pick up a 2018 scott foil RC for a great price, so i am curious what people's experiences are in general and specifically with the scott foil rc.

some things i am curious about:

1.) how does braking power / modulation / feel compare to "normal" seatstay mounted rear brakes?

2.) is there a particular brake caliper that performs above and beyond all others? (i am thinking eeBrake maybe?)

3.) does it get a lot dirtier than the seatstay mounted brakes? (the dude at the LBS told me i had it the wrong way around when i mentioned the chainstay mounted brake would get dirtier -- he said that in fact the seatstay mounted brakes get dirtier. is this accurate to your experiences?)

4.) does anyone have experience with the new scott foil with the chainstay mounted rear brake? how does it perform?

5.) the 2018 scott foil rc has dura ace direct mount rear brakes under the chainstay-- are those substantially better than the old ultegra 6810 direct mount? (i read in a review of a scott foil 20 that the ultegra brake felt "spongy"....)

anyway... thank you!

best,

o

by Weenie


C36
Posts: 291
Joined: Fri Mar 03, 2017 3:24 am

by C36

Can’t answer on the stopping power, my experience is limited and the set up was very different from what I used to... but on the dirty part of things:
- a lot less braking dirt under the rain (with wheel rotation the projections are made to the floor rather than to the seat stays and seat tube). Now when it rains a lot your entire frame will be dirty...
- more road dirt on the brakes (mix of front wheel projection and closer from the ground) and position a bit trickier to clean.


Envoyé de mon iPhone en utilisant Tapatalk

bremerradkurier
Posts: 264
Joined: Mon Jun 13, 2016 4:18 pm

by bremerradkurier

There's a reason under chainstay brakes faded from use for mid 80s MTBs within two model years...

User avatar
Beaver
Posts: 499
Joined: Wed Aug 18, 2004 6:06 pm
Location: Lower Saxony - Germany

by Beaver

I really thought about buying a Foil, but that brake kept me away from it.

Canyon tested these bb mounted brakes to have NO aerodynamic advantage. Scott agrees, but claims the missing brake bridge improves compliance of the seatstays. The Aeroad is a bit softer than the Foil, so seatpost design matters more, it seems...

If the frame is not really stiff, you will probably have brake rub, when you are out of the saddle, brake performance is worse and the brake is harder to clean and might touch your powermeter...

spdntrxi
Posts: 1837
Joined: Sat Jul 20, 2013 6:11 pm

by spdntrxi

I think the biggest things is modulation. I have 2 bikes with rear brakes down there... BMC TM01 and a Madone6. The BMC is OEM brake..it works good enough for a TT bike but it's a pain to adjust well. It works and I and no longer rubs (well worn shoes) and I call it done. I have some verson of the TRP on the madone which I started using because other stuff would hit the stages PM..The front brake is still a circa 9000 series Dura Ace which feels heaps better. I have a DM EE, but since it's my wifes bike and she rarely uses it off the trainer.. I'm in no hurry.

shimmeD
Posts: 434
Joined: Thu Jun 28, 2012 10:52 pm
Location: eNZed

by shimmeD

Why should it work differently? Different brakes or/and different cable route, so if you use EE brake there should be no difference if the route is good (no sharp change of directions etc).
It's harder to remove and install the rear wheel, because there is less distance between tyre & brake (chainstay bridge or bottom bracket in the case where brake is located traditionally). Otherwise there isn't any other significant disadvantages IME.
Less is more.

User avatar
Calnago
Posts: 6466
Joined: Sun Nov 07, 2010 9:14 pm

by Calnago

Not a single “pro” to be talked about with that brake placement.
No, it will not work as well. I’ve never seen a smooth friction free cable routing to brakes mounted down there, at least when compared to brakes mounted on the seatstays. Adjustment is a PITA. Grit and road grime is constantly getting thrown at it. Yes, they get dirtier than seatstay mounted brakes. Wheel removal is finicky sometimes. And clearance issues often arise when you try to do other things, like maybe a stages pm for example. Heed what @spdntrxi says in his post above. A large part of modulation is a function of how smooth the brakes operate, and it’s hard to achieve any kind of real smoothness with that cable routing.
The only reason they exist is because somewhere along the way some “aeroguru” probably ran some test that probably showed a milliwatt of aero benefit or something. Trek abandoned it. Colnago (on their VR-1) abandoned it. The pain vastly outweighs the gain.
Last edited by Calnago on Tue Jun 12, 2018 9:47 pm, edited 1 time in total.
Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ

octave
Posts: 99
Joined: Sun Jan 15, 2017 8:47 pm

by octave

hey everyone,

thanks for the input. calnago seems to have really put the nail in the coffin-- both trek with their madone and colnago with their vr-1 did indeed shift away from the chainstay mount... such a bummer as i really like the latest generation foil's aesthetic (i know many people hate it!).

it is surprising that some companies (felt is another example) put this chainstay brake on recent models. i was hoping for "good" news about this, but i think it was wishful thinking....

best,

o

shimmeD
Posts: 434
Joined: Thu Jun 28, 2012 10:52 pm
Location: eNZed

by shimmeD

I'd have to say now that it makes more sense not to break away from tradition in this case. The disadvantages of chain stay mounting are not that bad once you learn to live with them. Winding back, would I change my bike? Only a maybe.
Less is more.

jlok
Posts: 638
Joined: Tue Jun 30, 2015 3:30 am

by jlok

the brake will block 4iiii or Stage power meter sensor, be careful.
Giant Propel Advanced SL Disc 1 < Propel Adv < TCR Adv SL Disc < KTM Revelator Sky < CAAD 12 Disc < Domane S Disc < Alize < CAAD 10

octave
Posts: 99
Joined: Sun Jan 15, 2017 8:47 pm

by octave

thanks for the heads up on the stages/4iiii clearance issue... i use favero assioma pedals so not a problem there if i do go the foil rc route. but, i am less and less likely to in light of most responses to this thread.

Tango
Posts: 14
Joined: Mon Feb 27, 2017 9:37 pm

by Tango

To make it harder: I own a Scott Solace with same the rear brake and personally don't feel a difference (especially since most stopping is done by the front wheel).
Changing wheels is easy, because i can open it from the handlebar.

For me it's a lot of hearsay from times when only proprietary solutions by OEM existed.

cunn1n9
Posts: 97
Joined: Sat Jan 15, 2011 1:24 am

by cunn1n9

I have never used them so cannot comment on functionality but would expect that they would get more water spray/dirt on them from the front wheel spray. From the rear wheel spray it actually should be less as the wheel has further to rotate (about 90* more) before reaching the brake from the contact point on the ground. However I think this is insignificant.

I think adjusting brake is the biggest pain and if you use a work stand where the B.B. is a resting point it will not work. I use a park tools stand and this wouldn’t work with B.B. mounted brakes.

On the plus side I’d say aesthetically I actually like the look as there is no cable arcing out of the top tube and no brake so looks clean. You hardly notice the brakes in that position with the cranks hiding them so I kind of like that. The Foil with direct mount front brake and the B.B. mounted rear brake looks great in my opinion.

Plus I’m and Aussie and Matt Hayman won PR on a Foil so I like it for that too!


Sent from my iPhone using Tapatalk

User avatar
Beaver
Posts: 499
Joined: Wed Aug 18, 2004 6:06 pm
Location: Lower Saxony - Germany

by Beaver

Maybe the next generation will have the brake back on the seatstays. ;)

tarmackev
Posts: 239
Joined: Sat Jan 15, 2011 9:59 pm

by tarmackev

Wow, a lot of hate.
I had the Scott Solace with the brake there and the only negative was a little more lube but overall there was nothing. The Solace had direct mount so a little more power and slightly lighter I believe.
It’s not something I would consider when buying a new bike but I do keep my bikes very clean.
I’m guessing if you avoid maintenance then it could potentially be an issue.
Funny thing is it only gets dirt from the front wheel and not the rear.
Don’t know anyone who owns a Foil who ever had a problem with the brake.


Sent from my iPhone using Tapatalk

by Weenie


Post Reply
  • Similar Topics
    Replies
    Views
    Last post