need help: brakes

[nowindinmyhair]

Ok, weekend's here. I started looking at my scraping noise (on my '84 Venture). Didn't think it was the brakes but when I put the bike on the double stand, the rear wheel was not turning freely. Could not remove the rear pads so I took the caliper off. Now the pads fell out and I have to say that they look almost new (thickness wise). There was a small metal plate covering about 1/2 the piston on the piston side of each pad. The small plate hooks on to the pad. It has an arrow on it.

 

Can I take the plate off ? If not, which direction does the arrow point (front or back)? Is there an adjustment somewhere to take the pressure off because the pads are always in contact with the rotor and prevent the wheel from turning freely.

 

Thanks in advance.

[Dano]

Sounds like you've got a stuck caliper. If you have a c-clamp, you could put a pad in there and gently try to turn the c-clamp and see if the piston goes back in. If you don't want to use a pad, use something of the same thickness that will cover the piston so you can get it back in straight. If it is stuck, you could also back out the bleeder screw and you should get some fluid out of there when you apply pressure to the piston. As far as the metal piece, I'll have to look at mine to tell.

 

Dan

[Marcarl]

can you post some pictures?

[Squidley]

Here is a post on a possible answer about the return vent being plugged, I have had this happen to me on my 1st '86

http://www.venturerider.org/forum/showthread.php?t=12419

The caliper being sticky too is another option.

[greg_in_london]

It may be that your pistons are seized - after all, if the linked front brake is still working, then the fluid return valve is likely not the problem.

The standard linked system (which I think is awful and should be removed, but it's up to you) has lots of restrictions in it - a restrictor valve to reduce pressue on he front brake and a proportioning valve which reduces braking power at the back when you're slowing down and between these a lazy piston gets every opportunity to stick.

 

While it's apart, push down on the brake pedal and see if the pistons move freely. (Don't keep doing this or you will drop the piston onto the floor. This would make the job easier to do - cleaning the piston - thoroughly, but a bigger job) If it begins to move, but is corroded, try cleaning it with an old toothbrush and brake fluid (put some goggles on or be careful). If you have some (red) ruber grease, lubricate the piston with that before you puch it home again. You may have to do one piston first, then push it back and hold it in place with vice/mole - grips while you do the second one.

 

As to the metal plate - the manual shows a spring above the pads and says to change it when the pads are changed. I have always refitted these without a problem. On bikes which have the additional plate, I refit it the way it came off. It doesn't seem to be important, though, and the manual does not mention it at all - sorry I can't help more. I'll see if mine has them when I fit a new back tyre. (This afternoon or during the week)