Road Bike, Cycling Forums banner

1 - 3 of 3 Posts

·
Registered
Joined
·
2,227 Posts
Discussion Starter #1
I'm trying to install my old froglegs on a new frame and am having a problem--on the mounting studs on the bike, there is a shoulder, so the brake arm slides onto the stud and stops at the shoulder, then is held on with a bolt, no problem. My problem comes when I add the spring, as it appears to have more thickness than the width of the shoulder on the stud, so I am unable to tighten the mounting bolt or it causes the brake to bind--anyone else have this issue with these brakes or have a workaround?
 

·
Registered
Joined
·
19 Posts
It is usually a result of the stud having too much paint or clear coat on it down towards the bottom of the stud. There is a special cutting tool for this which works best. It is called a brake boss mill. It is a small mill that slides down over the stud and cuts and smooths the pivot seat at the base of the stud. They are hard to find and most LBS don't even have them, but they are indespensable when working with canti brakes. You can also careully use a file and some emery cloth to acheive the same effect. It is not the brake that causes this it is usually the stud, however in some cases the bushing on the canti stud can become dislodged and therefore the bolt bottoms out on the canti before it hits the top of the stud. But seeing as this is a new frame I am guessing the paint just needs a little dressing up.
 

·
Registered
Joined
·
2,227 Posts
Discussion Starter #3
Thanks, I think you are right in that there was paint overspray on the bosses. What is strange is that the brakes fit on there correctly without the springs, but when I add the springs it makes them too far out on the stud. I guess asking mr. Merckx to mask off the damn studs on a $1000 frame is too much trouble.
 
1 - 3 of 3 Posts
Top