Tight/Stripped/Weird Rear Caliper Bolt

[arronjackson]

Hey Forum,

Trying to pull my rear caliper and the bolt that holds it to the bracket (the one of the two towards the front of the bike) is super stiff. It takes an unreal amount of torque to unscrew and once it does start to move it's very difficult to turn and doesn't seem to back out.

I had the bracket incorrectly installed (off the swingarm alignment groove) for a while but recently fixed that issue. The bike brakes fine now and there are no damaged parts, as far as I can tell, from the incorrect installation.

Has anyone every had trouble with this bolt? I can't see it from the back side, I'm not sure what to do.

Thanks,

 

[Motogiro]

If the assembly was assemble in a misaligned state, there may be a chance the bolt has been bent. That bend in the bolt will add up to binding in it's it's bore. I would lube it and back it out completely once you have a replacement. It may also have loctite on the threads.
https://www.ronayers.com/oemparts/a/yam/500460eaf8700209bc7952d8/rear-brake-caliper

 

[TownsendsFJR1300]

Just checked that front bolt on mine. It has threads right beyond the actual hex head. The caliper "floats" / centers itself on that bolt.

You can't see the "end of the bolt" as it's INSIDE THE caliper. (The adjacent rubber boot should be full of BRAKE GREASE).

I suspect the aluminum threads of the caliper are now boogered up. It is possible the bolt is bent too, but just the spinning in place tore up some threads(the aluminum threads being softer than the bolt). Torque on that bolt should be 20 lbs / ft

I's get a real good pair of vise grips, grip them as hard as you can on that head and start spinning CC maybe using a screw driver BEHIND IT FORCING IT OUTWARD (OFF) the caliper.

In the end, once it's off, count on either a replacement caliper or heli-coiling it.

Good luck and please post back how it works out...

 

[TownsendsFJR1300]

Any updates???

 

[arronjackson]

I haven't had a chance to monkey around with it. I've got the replacement bolt, I'm just not looking forward to opening this can of worms. My rear wheel gets over one spin by hand which is better than before. The brakes work still but I intend to replace the cylinder seal once I get the caliper off. Maybe this weekend I'll get the ambition to get started.