I haven't been here in awhile, so you may or may not remember me. I bought a basket case, with what I believe to be are '79 forks on a hardtail frame, and a XLCH '74 engine. It has two disks in the front, and one in the rear so obviously it isn't the stock brakes for a '74.

So anyways, the caliper isn't working properly. THeres no air in the lines, and when i step on the brake, the pads close, but there isn't any force behind it, it doesnt slow the bike down at all.

So I was going to retrofit a newer caliper on the rear, but before I can do that I need to know what is on there now, so I have a jumping off point as to the age and model. I can provide more pics if necessary.



It has a integral mount that comes off the bottom at a 45 degree angle. THe saddle bag is in the way.

 

Sorry, but I do not recognise that caliper. Hopefully someone will come along who does.

 

Hi, EvilWayz,

Your calipers remind me of some I observed on an old Triumph but I'm not really sure. I do know of an interesting website, https://www.vintagebrake.com/. These guys might be able to id it for you. They also might be able to find pads and other parts.

Good luck and keep us posted!!
CatWoman

 

Looks just like the GMA caliper that's on my Shovelhead....

 

More pics ...

http://www.jpcycles.com/brake-calipers/gma
http://beltdrives.com/gma-brakescont...l-b-calipers-2
http://www.ebay.com/sch/GMA-Engineer..._563200/i.html

 

That's a sweet ride. Ive been trying to figure out what to do with my rear fender, as I bought tin for a softail and retrofitted to my bike, and now I'm trying to figure out a way for the rear ducks fender to work.


So I think my caliper is a GMA R10, or a copy of one.

Can these be rebuilt?

 

The only ones I have rebuilt are the OEM for 1978 to ~1982. Very simple device. Only a few parts. But you do need compressed air to pop the pistons out. And it is important to read the FSM for general information.

I expect that they are all about the same. Search YouTube, google, etc for rebuild GMA caliper.

GMA Motorcycle Brake Caliper Rebuild Kits
http://www.jpcycles.com/motorcycle-b...build-kits/gma

Shovelhead Rear End Re-do. Part 3: GMA A Caliper Rebuild/Rework
http://www.chopcult.com/news/blogs/s...-22-40-28.html

I do not see GMA here specifically, but the others should have useful info ...
https://www.youtube.com/results?sear...ld+GMA+caliper

 

Thanks for the tip on the AC compressor. My buddy has a full machine shop, down to a forge to make custom sissy bars. I'm sure hes got a compressor.

 

From your description of the problem I don't think that the caliper is the problem, it may be the piston in the cylinder.

 

Exactly. Plus, it will be cheaper to rebuild the brake than buy a new one.

Can anyone tell me the name of the brace or strut that attaches to the arm on the caliper to the frame? Right now mine is held in place with a piece of angle iron and its ghetto as hell.