Recessed Nuts
 

I recently bought a pair of brake calipers off fleabay. The rear brake has recessed nut/mounting as it should, but the front caliper came with the older standard nut (and no, the seller didn't mention this little detail).

Can I just buy something off fleabay like this (New Bike Bicycle Brake Recessed Brake Nut 30mm BE13162 | eBay), or do I need to buy the entire screw and bolt pair (which I cannot find anywhere).

Yes, they come in varying lengths to suit your fork thickness.

$4.99 for that?

The last time that I bought a brake caliper it came with four different length recessed nuts. Assuming that's common I'd think every LBS must have a drawer full of the things. If they like you that might even be a "gimmy".

I'm not sure from your description but did your front brake come with the newer short mounting bolt but was missing the recessed nut or was the brake fitted with the old design long mounting bolt that uses an external nut?

If it has the current short bolt, recessed nuts available in a variety of lengths and, as noted, most LBS's have a bunch of extras.

If it has the old, long mounting bolt, either return it to the seller or your fork crown must be narrow enough to let it stick completely through so the external nut will fit. If your fork will work, you can drill out a short recessed nut with a 15/64" drill bit and use it as a bushing in the rear hole.

The issue isn't the nut but the mounting bolt on the brake. If it is short enough to end short of the far side of the fork by 3mm or more, with the thread ending about 10mm or so in, then all you need is the right nut. The same applies if the thread ends deep enough that you can cut it to fit.

But if the unthreaded section reaches to within 10mm from the far side you need a new brake or a new bolt.

Are you trying to say that you have a nutted front brake and a fork that needs recessed mounting? I could be wrong, but that's how I read your first paragraph. If that is the case, all you need is a bushing to decrease the size of the hole in the rear of the fork.

https://www.rivbike.com/product-p/brz2.htm

I use a Nutted front brake on a fork with a flush nut recess.. I just put a Flatwasher under the Nut.

the pulling the Brake-front against the fork, tightly, is steady enough ..

benefit : you can fit a Mudguard mounting, L bracket, under the Nut, easily..

Doesn't that result in the brake being slightly tilted back because the bolt is not centered in the rear hole? You always say "take it to a shop". That's an example of why I don't. "If you want it done right, do it yourself".

It doesn't necessarily cause the brake to cam over, but doesn't prevent it either. I agree that the job calls for a bushing (drill out a recessed nut) or washer that pockets well in the counter bore to bring the nut beyond the fork's face, and ensure stability.

Make do is OK when there's n o choice, but when doing it right is so easy, there's no excuse not to.

Why didn't I think of drilling out a spare recessed nut? I could have saved myself a dollar and a trip to Rivendell.

no , the flat back of the brake assembly, is pulled firmly against the flat front of the fork crown and with sufficient torque on the bolt it doesn't move

tried one of those nylon bushings like RBW sells .. the brake moved more because of the softness of the bushing..

Were that made in Metal that may be less of an issue..

Specifics .. Brake: older Campagnolo Record.. single pivot., Frame/fork : Bridgestone RB1.
in use for 22 years, now..

Because you're not me?


-----Sorry, I couldn't resist.

I'm incredulous.

Would it be more believable if Grant put it in the Rivendale reader ?

Thanks for helping me clarify folks. The front brake did indeed come with the old longer design bolt and external mount. I'm assuming the seller lost the original short recessed setup and replaced it.

I'll start looking for the newer short bolt and recessed nut then.

Thanks for helping me sort this all out everyone.

Just about the only likelihood is that the hardware was switched. Most likely it's a mixed set from two generations.

You have a pretty easy choice. You can buy or improvise a stabilizer bushing as we described earlier, or if the non-threaded part is short enough cut the bolt and buy a recessed nut.

This ain't that difficult. Thread on the appropriate die (6mm?), cut a few threads as needed, hacksaw off the excess bolt length, apply a file to round the edges, remove the die, and you're done. This is a less than 5 minute job, and free. The nut - well your LBS will have plenty to choose from, and cheap, too.

IF you happen to own the appropriate die.

You mean tools aren't considered as free? ;)

Especially something like dies that you don't use every day. I own a few taps but I don't think I have any dies - I'd have to look in the seldom used tools box.

The threading suggestion presupposes owning a die, and more important that the bolt is sufficiently soft to thread with a die. Better quality bolts (and many cheap ones) are heat treated to fairly high hardness and not that amenable to threading. Trying to do the job and finding that out means the loss of both the brake bolt and die.

The $1.00 fix of adapting a washer or drilled out brake nut is the way to go.