amahana1

Anyone know where I can get a rear disc brake bracket. I am going to have a local frame builder weld one to a steel bike and for the life of me I cant find one. He said just bring him in a bracket and the frame and he'll weld it on for me.

pmseattle

What kind of frame ? You may not need it welded. Check out www.a2zcomponents.com

amahana1

Surly Crosscheck

pmseattle

Well, I was thinking of the A2Z DM-UNI disc brake adapter, but I don't think it would work with the cross-check dropouts.

mtbikerinpa

I made the one on my bike with a grinder, but here is a place that makes them now. Scroll to the bottom of the page.
https://www.gaerlan.com/bikeparts/parts/disk/disk.html

amahana1

Perfect, exactly what I need. Thanks

namaste1978

If the builder that is going to weld it for you tells you to bring the mount than you should think twice about going to them. They should be able to fabricate them for you or have them available. Doesn't sound like they have much experience in that dept. I've gone through this before! I have the "one trick Surly" in the Cyclorcross forum.

amahana1

Yes you have a point, however hes the only guy around with bicycle frame building experience that is even remotely close to where I am. I thought about exactly what your saying. The only thing I can think of, is that the guy builds replicas of vintage bikes....like 18th and 19th century so he doesnt do disc brakes that often but his work is immaculate. I am in the very early stages of this process and am I still looking at my options. As much as I would like to send the bike out to some one out of state who has probably done a lot of this exact fabrication, it would be way to expensive to pay for shipping there and back, and if something wasnt right when it came back...to ship it there and back again. Yes I have seen your Surly and its close to what I am shooting for as far disc brakes go anyway.

mtbikerinpa

The procedure is simple enough that anyone with welding skills can do it. But the mount has to be made to 1mm +_ precision or the caliper will not mount. Thus it is not at all cost effective to have the installer fab a bracket when a pre-fab bracket costs a mere 12+shipping.

namaste1978

Just as a side note to that, you didn't specify if you were going to run it geared or single speed. If you choose to run SS you might have to have a bracket that can be slotted so you can take up the chain slack for different gear ratios. I have always ran 42-18 for everything so when we welded and fab'd the bracket, it didn't have to be slotted. Normal off the shelf brackets are not designed to be slotted for SS use. If your building the bike up geared though, the bracket that Mtbikerpa recommended looks pretty nice. The lower end of the bracket will need to be shaved to sit flush on the weird semi-horizontal dropouts on the Crosscheck. Goodluck!

amahana1

I am having trouble visualizing what you mean by slotted. Isnt the brake on the non drive side? Nm... You mean slotted so you can actually move the caliper back a little to account for moving the wheel back to take up chain slack for different gear sizes. Is this right?

amahana1

In that case, wouldnt something like a chain tensioner work? Forgive the ignorance on my part, this is the first single speed I have attempted. I have done a dozen geared bikes but not SS.

namaste1978

The disc brake mount needs to be slotted like the one in this pic you you can take up the chain tension and also have the caliper perfectly alligned over the rotor. It's tricky business!