Topic: Front brake not retracting??

[benmanuel]

So I changed my front brake pads, but I think the piston isn't retracting very well when the brake is released. If I apply the brakes as normal, it doesn't grab very hard, if I pump it again it grabs like crazy. At first I thought it was air in the lines but they've been bled twice now and it's still bad. I cleaned the piston and the caliper when it was apart the first time, it's not seized.

Is there any EASY way to force the piston back to its original position without dismantling things too much?

Maybe removing the floating caliper and then applying pressure to the back of the main, forcing the pad and piston inward?

I really really don't want to drain and refill the and drain the system again.

[Patrick]

I think your issue lies in your master cylinder. There are two small holes in the bottom of the master cylinder reservoir. One pumps fluid to contract the brakes, one allows fluid return the contract the brakes. Make sure both of those are clear. You may be able to accomplish this without tearing down your brake system, but draining the master reservior likely would work best.

Patrick

[benmanuel]

They both appeared to be clear when I had the reservoir open, nothing seemed to be clogging them.

[WFO]

I use a c- clamp to push the piston back in also how tight are the brakes after you pull the lever? they are going to be tight for awhile also you just might have to bleed your system or replace all the fluid if it's old (now is a good time) and then go from there if you have the same problem.

[gold72]

You can use a c-clamp to push the piston back to its original postition, but just be carefull not to push too much fluid back up into the master cyclinder

I would double check the holes in the mc, use a small wire or a sewing needle to clean out the little hole

when you retract the brake lever does fluid squirt out of the little hole, if not than it is clogged up

[benmanuel]

You can use a c-clamp to push the piston back to its original postition, but just be carefull not to push too much fluid back up into the master cyclinder

I would double check the holes in the mc, use a small wire or a sewing needle to clean out the little hole

when you retract the brake lever does fluid squirt out of the little hole, if not than it is clogged up

I'll try and find a c-clamp to use for this. And yes the fluid DOES squirt out when I retract the lever, the system seems to work just fine, as it's been bled and refilled.

I think the piston just isn't completely seated and therefore I can't adjust the brake properly or get full application in one pump.

Thanks guys!

[RRRToolSolutions]

It's the small return hole in the master cylinder. I've been there- done that. You need to drain the flid out of the system, remove the internals of the master including the cup clip, piston, and spring (best done off the bike). Once those are removed, you can try blowing air, but often it will take a small wire - like that found in a steel brush. I have a torch cleaner tool which is easy to use.

It's important you get that fixed - it causes undue wear, unnecessary heat and can boil the fluid which means no brakes on initial application, and is so easy to get right. It's not in the slave cylinder - it's that small hole and piston relief ports not working. Honda, Suzuki. Yamaha, and Kawasaki all have the same 2 holes. It's the smaller of the two so your problem is common and the first to manifest itself.

Regards,
Gordon

[MCRider]

So I changed my front brake pads, but I think the piston isn't retracting very well when the brake is released. If I apply the brakes as normal, it doesn't grab very hard, if I pump it again it grabs like crazy. At first I thought it was air in the lines but they've been bled twice now and it's still bad. I cleaned the piston and the caliper when it was apart the first time, it's not seized.

Is there any EASY way to force the piston back to its original position without dismantling things too much?

Maybe removing the floating caliper and then applying pressure to the back of the main, forcing the pad and piston inward?

I really really don't want to drain and refill the and drain the system again.

Youlll have to determine is it the caliper or the master cylinder. Loosen the bleed valve on the caliper. If you can pry the pad back into the caliper easily, like with a tire iron and a shim, then its the master cylinder (my bet).

If its the MC, I never had the patience to rebuild one, and I've had two fail. I just went to Cycle Recycle II and got another one for cheap each time. Even used a Kawasaki one time.

Other posts here are helpful if you go the rebuild route.

[Bido]

I had the same problem with my 78 F3 I found that a lot of dried brake fluid had built up behind the seals which caused my problems I removed the piston seals and cleaned the grove with a dremel tool fitted with a wire brush. I replaced the seals with new ones while I had the brakes apart and no problems after that.

Good Luck

Bido