Need help finding a set of calipers....
 

Trying to put a set of dual pivot calipers on a 1989 Trek 420. It's an odd year that I'm going to call "transitional".

Both brakes are 47-57mm reach (single pivot). The front brake is recessed, and the rear brake is nutted.

So just about any modern caliper will fit the front, but I'm having trouble finding something for the rear.

Shimano makes the R450 and the R650, both long reach, but both are recessed. I think with a little work I can drill out one side of the brake bridge to fit the allen nut thinger on the brake..

Thoughts?



Current rear:
http://i.imgur.com/W51z6.jpg

Use another front caliper on the rear. The pivot will be long enough to pass through the bridge with room for a standard M6 nut to hold it in place.

my thoughts exactly! I hate the idea of drilling anything on a bike. BTW are you sure the fork was not a replacemnt/warranty thing?

Have you checked the rear bridge to make sure that it can't take a recessed nut? I find it odd that a manufacturer would have both types of brake attachment on one bike.

I have 2 treks and a univega with this same thing, the forks are not replacements. I couldn't tell ya why anyone did this.

That's why I say it's a "transitional" thing... Who knows. :)

I have a brand new set of standard reach Tiagra calipers (too short for the rear, just right for the front) I'll see how the bolt from the front brake fits, but my guess is that it's not wide enough to adequately fill the hole so it is stable.

Man, those current brakes look so good it would be tough for me to swap them out for additional braking power.

I guess my thought would be why not just replace the front only save yourself a bit of headache and put the dual pivot muscle where it counts the most.

Just tested this out. Looks like it will work perfectly.

Looks like I can get 2 front R650's and I'll be in business. Thanks for the idea!

J&B Importers has the BR650 in standard nut, and recessed nut, front and rear sold separately. There is a god!