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View Full Version : Mounting sidepull brakes on the back of the front fork



sauerwald
10-27-07, 06:41 AM
I am planning on having a new bike built next year, and have been looking at many of the details of the bike. The primary purpose of this bike will be to serve as my daily commuter - I have a 30 mile RT commute which I do most days, year round.

Some of the basics which I am starting from are that it will be a steel, brazed, lugged frame (I have one other custom bike, done for me by Peter Mooney, and I love it). I want the drive train to be based on the Rohloff hub. I will run relatively heavy tires (I currently use Schwalbe Marathon Plus), and want fenders on the bike, which limits my choice of brakes for the bike. I am not sure that I am comfortable with disk brakes, which further limits my choices. I have been looking at the Tektro R556 sidepull which looks like it would provide sufficient clearance. In looking around at other bikes, I noticed the Thorn Raven Sport Tour ( http://www.thorncycles.co.uk/ravensporttour.html ), which has the front brake calibers mounted on the back side of the front fork. Since I place the lever controlling my front brake on the right handlebar, this would make cable routing easier, and I like the fact that during braking it places the brake under compression force rather than tension (my engineering background coming out).

My question to those of you who design and build frames - why don't you see more bikes like the Thorn Raven with the brake caliper mounted on the back side of the front fork?

Peterpan1
10-27-07, 08:22 PM
In the review it says the reason is to eliminate brake squeal, which is really brake model specific issue to the extent it isn't instalation or maintenance. Structurally there really isn't any advantage since in a normal instalation one brake is in tractor and the other is in pusher formation, so it is designed for either. Either way the stud is going to be simultaniously in compression. A sidepull, if it's stud broke, might remain functional for a moment if the brake was jammed behind the fork, and still under compression. Another pottential advantage for the users of oversized brake blocks is that those blocks can get trapped by the fork, making wheel removal difficult. With the brake behind the fork, the long part of the block is aft of the brake and fork, however the Thorn appeared to use normal length brake blocks so the problem probably didn't manifest itself. Moving the brake aft of the fork would make it simpler to fit racks and panniers that sometimes foul brakes, though that is moreso a problem with brakes other than V brakes.

The normal brake position allows the brake's stuning design to be easily visible, and makes it easier to service the brakes. Concensus seems to be that the long reach centerpull is not quite up to heavy use f