fitting a rear brake on fork
 

I bought a Shimano Sora brake for an older fixie that I once had. I want to reuse the brake but put it on a new fork I just bought. Since it is a rear brake the mounting bolt isn't long enough. I've been looking online and haven't seen any place that sells a longer bolt. If anyone has any idea how I fit this brake onto my fork it would be greatly appreciated!

Hit the Bike Shop. The Nuts for recessed type brake mountings come in a variety of lengths.

you might try looking for a longer nut. really.

because front forks have become deeper in recent years, there are some pretty loooong ones out there. beware the brake housing attachment may be, or may not be, on the opposite side than you might expect it to be on when mounting a rear brake on the front. :)

The good news is that new brakes often come with several recessed nuts of various lengths. That means that every LBS probably has a drawer full of them. If they like you that might even be a gimmy.

The bad news is you might have to drill out the rear of your fork to fit the recess nut. That's not a very big deal. Just remember NOT to drill all the way through to the front.

Sometimes you cannot find a nut long enough, like when using a rear brake on a fork with a thick crown. Or when the fork isn't drilled for a recessed nut.

Here's the workaround for these.

Buy a recessed nut about 1" long (or more). cut off the head along with 1/8" of the nut which you may need later. Now you have a threaded coupler. Buy a stainless 6mm cap screw. Measure and cut the screw (or buy the right length) so it reches through almost but not quite, to the brake bolt. Mount the brake, and position your coupler in the middle of the steerer and spin it onto the brake at 5-6 turns or about 1/2 way. Now use the cap screw to catch the other side and pull everything tight. (It's important that the coupler is roughly centered so at least 5 threads are engaged on both the brake and screw).

If the fork is frilled for a recessed nut, drill out the head you saved earlier to 6mm, and use it as a filler/washer in the back of the fork.