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Dromen
10-08-2012, 04:07 PM
I have a mid 80's Trek 400 series road bike converted to single speed for my daily "treks" around the city. The original brakes needed replacement. I have plenty recessed brakes laying around. Front was no issue as it requires a recess nutted caliper.

Rear is another story. Went to install sister caliper from the set and the rear is nutted to the brake bridge. I don't have any experience with nutted calipers but all this appears to be is a recessed front brake that is nutted to the bridge. I would do the same with the sister rear brake but the threaded bolt is too short to feed thru the bridge.

So my question:
Can a recessed front caliper(with longer threaded bolt) be used as a nutted rear brake he rear as long as the bolt extends thru the bridge far enough to accomodate the nut?
oldpotatoe
10-08-2012, 04:12 PM
I have a mid 80's Trek 400 series road bike converted to single speed for my daily "treks" around the city. The original brakes needed replacement. I have plenty recessed brakes laying around. Front was no issue as it requires a recess nutted caliper.

Rear is another story. Went to install sister caliper from the set and the rear is nutted to the brake bridge. I don't have any experience with nutted calipers but all this appears to be is a recessed front brake that is nutted to the bridge. I would do the same with the sister rear brake but the threaded bolt is too short to feed thru the bridge.

So my question:
Can a recessed front caliper(with longer threaded bolt) be used as a nutted rear brake he rear as long as the bolt extends thru the bridge far enough to accomodate the nut?

Yep, do that all the time.
Mark McM
10-08-2012, 04:28 PM
Yep, do that all the time.

... just don't forget to flip the brake shoes around, so the pad insertion slot faces the rear.
Ken Robb
10-08-2012, 04:32 PM
or drill the hole to fit the modern hardware you have.
Dromen
10-09-2012, 07:59 PM
does drilling the brake bridge required diamond cutting precision or can on goof with a bike stand and a drill handle the slight enlarging of the hole?

If drilling is an option, do i need to "seal" the newly exposed metal?
Louis
10-09-2012, 08:07 PM
^^^^ That's the type of job I would be willing to try myself. If I can do it (easy access, simple tools) then certainly you can too.

If you have some primer on hand you could use a Q-tip and put some on if you like. I wouldn't bother buying it for a tiny job like that. Or you could glop-up the hole with grease, then wipe it down once you're done installing the caliper.

I say go for it.
Dromen
10-09-2012, 08:11 PM
Louis,
considering your nearly 11,000 posts, i a beaming with confidence.
Louis
10-09-2012, 08:13 PM
Louis,
considering your nearly 11,000 posts, i a beaming with confidence.

I don't think the number of posts correlates with much ;)

Good Luck
Louis
10-09-2012, 08:21 PM
BTW, I used to have a Trek 400. I rode it for many years, until the DT cracked. (due to T-bone collision with truck a few years before that)

I didn't realize it at that time, since that was the only road bike I had, but that thing was a noodle. Once I got a "real" bike I was amazed by what better (quicker) steering geometry and a stiffer frame can give you.
Dromen
10-09-2012, 08:27 PM
It is perfect for noodling around chicago. just enough dents, dings and chips to keep the undesirables away. nice straight frame and surprisingly detailed lugs for a "sport" road bike.

I keep thinking of sending it in for a paint job....but then there goes the charm and it gets too much attention.
Louis
10-09-2012, 08:32 PM
nice straight frame and surprisingly detailed lugs for a "sport" road bike.

And when it was new the cable housing color matched the decal colors. (Ecru frame, blue decals) A nice detail I didn't come appreciate until long after I had purchased it. For many new bikes they just use generic black housing.
Ken Robb
10-09-2012, 08:55 PM
You can paint the bare metal with nail polish too.
oldpotatoe
10-10-2012, 07:42 AM
or drill the hole to fit the modern hardware you have.

I wouldn't do this. Most are pretty thin and recessing the 'nut' will weaken it significantly, not even mentioning the difficulty in getting the bit in there straight. Geezzz, just get a front brake and not risk breaking the brake bridge.
Dromen
10-10-2012, 09:25 AM
You know, I was concerned about free hand drilling and getting an "proper" hole but didnt think about the strength(or lack of) the bridge. So, are you worried about the force needed to drill the hole either breaking the bridge at welds?
Louis
10-10-2012, 01:11 PM
So, are you worried about the force needed to drill the hole either breaking the bridge at welds?

I doubt it. You can control that by not pushing too hard as you drill.

He's concerned about the material lost when you drill the hole to a larger OD. The effect this will have depends on how beefy the brake bridge is to begin with and the stresses resulting from the braking forces. You sort of have to look at it and decide if you want to take the chance.
Dromen
10-10-2012, 02:04 PM
it would be an adventure but considering the cost of a new sharp drill bit and the chance of damaging/destroying the bridge vs the cost of a random front brake.....think i take the path "pay a few extra bucks with a bridge vs saving a couple with potential of a frame without a bridge"

Thanks for everyone's help in the decision.

Now i continue the search for the matching or similar front brake....See Classifieds for "WTB - Shimano SLR brake"