[ChopperDude]

Bikes with dual calipers (touring bikes), often have another problem, even easier to fix.

The outside of the piston (in the caliper, that pushes the pad outwards) gets gunked up from brake dust and road grime. It starts to "fight" the rubber o-ring that is supposed to pull it back in.

At our shop, here's what we do.... 1) take off one of the calipers 2) squeeze the lever until the pads press against each other 3) spray the outside of the pistons with brake cleaner, get a rag in there and clean them really well 4) pry the pads back apart gently 5) reinstall that caliper and repeat for the other side.

We get this complain often, and you'll be shocked what a difference you'll feel in the caliper.

Single caliper bikes don't seem to have this problem as often, possibly due to having more pressure available for the single caliper?

 

[ChopperDude]

After chasing down a nagging front brake problem for a while, I was left with nothing to do but either pay the dealer for some sort of "power bleed" procedure (which I'm sure they would have screwed up) or start looking at the calipers. I was pretty confident that the system was air free and after reading this thread took the calipers off. Bingo! Some of the pistons weren't even coming out of the caliper even after pumping the brake lever. Some would come out and then creep right back in like there was vacum sucking them back. Anyway, I wanted to thank you guys for the tip- I'm off to buy rebuild kits. Vic

Before you spend money on a rebuild kit, I'd just try to clean the piston, as indicated in my previous post. While you have the pistons protruding out of the caliper, spray them down with some brake cleaner... use a rag and get in there (maybe an old toothbrush would work?) and wipe them down.

Usually all it takes us is a little spray and a rag, and we change a spongy brake back into a rock hard one !!

 

[ChopperDude]

One question though to anyone who might know- any truth to what was told to inkonyou about the rubber band on the lever deal? Will any air actually bleed itself out through the M cyl by using this method? Thanx again fellas,
Vic

I heard of this recently myself. Only had the chance to try it once and it did seem to help in that case. I'd need to try it a few more times to see if there was consistency in improvement or not. Certainly is an easy thing to try if you're having a problem though, can't see that it would hurt anything.