Hi all,

I'm in the process of trying to upgrade the v-brakes on my wife's Cannondale Quick SL3, but need some help.

I acquired some Shimano XT (BR-T780) arms and levers. I installed the arms into the rear mounting holes without any difficulty. However, the mounting points on the front fork don't seem to have any mounting bosses in them, and the hole in the fork is much too large for the bolts that came with the XTs. The existing cannondale brand (promax) brakes use a course threaded bolt straight into the fork (which is carbon, if it matters).

I'm a bit at a loss as to how to proceed. Any help will be much appreciated.

Here are two pictures that will hopefully clarify the situation.

First, the rear mounting points, showing the boss that the brake slid onto:



And then the front fork image, along with the old brake:



The Shimano instructions I have lead me to believe that there should be a mounting boss in the hole in the front fork. Is this a standard item I can just buy from a LBS?

Thanks!

This is normal, and began with the advent of aluminum forks especially shock forks. You can't braze a steel boss to an aluminum strut, so they tap the strut to accept a threaded-in (and replaceable) boss.

I believe they are all, or at least mostly all, of the same 10mm(?) thread, but possibly someone will add to the thread and verify.

They are readily available if you search replaceable canti boss or something similar.

Yeah, looking a bit closer it occurs to me that the bosses may have just come off with the brake, and are now stuck on the removed brake.

Is there are straight forward way of separating them? Or am I just better off finding replacement bosses?

Probably you removed them with the old brakes, still attached to the mounting bolts.

No reason to buy new unless you damage them. You'll have to get them off the brake anyway (unless you're chucking the brake).

Find something that will allow you to hold the base of the stud solidly without damaging the thread much. Remove the front bolt as you would when removing the brake, and the stud is yours. When you go to install, there should be wrench flats, so you can get them nice and tight (tighter than you plan to tighten the brake mounting bolt). You might also use a light duty thread locker to ensure that they stay put next time. (many replacements are supplied with a thradlocker pre-applied).

Thanks all. I was able to get them off with a pair of linesmans pliers, and only minimal thread damage.

For whatever reason, the threads going into the stem had grease, not thread lock, on them.

The new brakes (Deore XT) are installed and seem to work well.