Bontrager Speed Limit rear brake problem.
Since late last August I’ve put 15,000 kilometers on my 2013 Trek Madone 5.9, and I absolutely love this bike. I’ve also done all my own mechanical work on the Madone, and I find that it’s almost as fun to work on as it is to ride.
So, after nearly a year of ownership, 15,000 kilometers in its saddle and dozens of hours in my work stand for routine maintenance, I think I have a pretty good feel for my Madone’s strength and weaknesses. Her strengths are many, and her weaknesses are few. The 2013 Madone, simply put, is a phenomenal bike.
My only complaint with the Madone involves the rear brakes. The 2013 Madone 5.9 uses Bontrager Speed Limit integrated brakes, which are mounted under the chainstay. Trek’s decision to mount the rear brakes under the chainstay near the bottom bracket is supposed to provide some aero benefits, and there’s no question that having the rear brake under the bike provides a nice, clean aesthetic. Unfortunately I don’t feel these two marginal benefits outweigh the downsides.
The rear brake, thanks to its mounting location, is constantly exposed to water, mud, grime and everything else the road has on it. Because of this, the rear brakes require frequent cleaning and servicing. Too bad the brakes are such a pain to work on…
The bolts used for these brakes are prone to rusting, and their heads will round if you’re not extremely careful.
The pad centering screws are located behind the crankset, and while one of the screws can (somewhat) be reached at an angle through the crank arms, the cranks must be pulled for unfettered access to the screws.
The stock brake pads and pad holders are absolute garbage. I replaced the pads and pad holders with the excellent SwissStop FlashPro Elite Black Prince brake pads and holders very early on.
But the real problem–the one that has been driving me absolutely insane for quite some time–is that the rear caliper doesn’t full open after a brake squeeze. It’s almost like it is sticking.
Here’s the brake immediately after adjusting (click to enlarge, note the caption):
Here’s the brake after one squeeze of the lever (click to enlarge, note the caption):
When I grab the brake arms and apply just a little extra pressure, they open the rest of the way. The brakes simply will not automatically open the entire way after a lever pull. I’ve spent countless hours trying to solve this problem, and nothing is working. I’m not sure if I have a defective brake or what. Note that the front brake has never been a problem, and is very easy to adjust and service.
Also, know the following: I have the dealer service manual and dealer installation manual, I’ve replaced the brake cable and the cable housing, the housing is cut to the proper length, the cable and brake lever are silky smooth and operating normally, the brake arms have been thoroughly cleaned and greased (many times) and the brakes are properly centered.
I would simply replace the brake with Shimano Dura-Ace if I could, but they have clearance issues with the Stages power meter. So I’m stuck with the Speed Limit brakes.
Any thoughts or ideas?