Front Brakes Stick

[Anonymous]

I have a '79 GS850 I can use the front brakes once then in order for them to release I have to blead them. Any ideas? Bad Mastercylnder? or Calipers? This is kind of annoying.

[SqDancerLynn1]

You need to clean the mastercylinder . Their is a fluid return hole that is pluged in the master cyl

[earlfor]

Your problem is as Lynn says. You have a blocked fluid return line in your master cylinder. There are two fluid lines in your master cylinder. One out, one in. I am not certain, but I believe the return hole is the one underneath the plastic cup in the cylinder. You have to remove the cup to access it.

Earl

[OklahomaPomade]

Where is the return hole for the rear master? Inside somewhere, I suppose?

[jrubek]

I'm having the same problem.

Thanks for the info. I am dealing with the same issue so I will be tearing down my master cylinder and replacing the reservior and underlying O-ring. The threads on the reservior are stripped and doesn't seal anymore. I'll take pictures if I am able to fix it. The only thing that I am worried about is the Clymer manual says the master cylinder is too complicated to be worked on by simple mortals and needs to be refered to the local Suzuki mechanic. Am I going to have problems once I remove the 2 screws at the bottom of the reservior? Any advice would be GREATLY appreciated.

Thanks,

Jeff

[courier11sec]

I don't think the reservoir has any threads. it's a snap fit with an o ring on mine (1981 GS850G) and I cleaned out the groove for the o ring with a pick.

[Road_Clam]

I have a '79 GS850 I can use the front brakes once then in order for them to release I have to blead them. Any ideas? Bad Mastercylnder? or Calipers? This is kind of annoying.

Brake fluid is a moisture "sponge" over time. Moisture that has developed in the brakes system will cause the aluminum to corrode. As well as inspecting/rebuilding the m/c, you also might have a brake caliper piston(s) that are sticking from a corroded bore. Use compressed air with a thick rag between the piston, and the caliper bracket. Gentilly blow some air into the bleeder hole to work the piston out of the bore (KEEP YOUR FINGERS AWAY FROM THE PISTON!). If the bore is corroded you can sometimes polish it up with #220 emery paper. If its badly corroded you need a new caliper.
Rich

[quakeholio]

If the calipar is not frozen I would just use brake fluid, not nearly as clean as air, but the piston is not as likely to go flying. If you have a double pot calipar then you need something to block the piston that is loser (there is always a lose one and a tight one).

If your pistons are really stuck in there I know how to get them out, but it's messy. Grease. Just take a bolt and screw it into where your banjo bolt goes and then crack the bleeder nipple open and start pumping away. It's much more controlled then compressed air, and the grease gun will put out far more PSI then the 150 or so of an air compresser.

Going through all of that my bet is that the MC has a blocked return. Giving the calipars a good cleaning is in no way a bad idea though.

[onchiman]

Ditto, Same thing happend to me when I picked up my 850 project bike. When loading the bike onto the truck I applied the front brake and it stuck. I used a turkey baster to empty the reservoir, removed the two phillips head screws at the bottom of the reservoir and then pulled it off. Some really amazing yuck was hiding under there and after I cleaned it out with brake cleaner and paper towels, i used a small wire off a wire brush to poke the return hole and clear it out. After it was good and clean, on went the reservoir and then I filled it and proceeded to bleed both calipers, running fresh fluid through the whole system. Worked great, no more sticking.

[OklahomaPomade]

again...what about the rear?

[jrubek]

Some really amazing yuck was hiding under there and after I cleaned it out with brake cleaner and paper towels,

What is brake cleaner? (Total Newby question). Is it a fluid? Can it be purchased through an auto parts store? Do I have to mortgage my oldest daughter to afford to buy it from a motorcycle shop? How is it used? What is your favorite color?

Thanks again,

Jeff

[onchiman]

It's brake parts cleaner and is very common at automotive supply stores and hardware stores. You may even find it at gas station/mini marts. It's cheap, maybe a buck or two and there are lots of manufacturers. It's also quite helpful when you accidentally get a little chain lube on your rear disk!

[Philly_Chris]

What's chain lube?




82 GS850G

[onchiman]

I have a '79 GS 850G. What's a chain?
Wait, maybe my chainsaw bar oil?

[jrubek]

Great, now the piston is sticking

Hey folks, I was having a problem with the front brakes seizing up. I could release them by releasing a little fluid from the bleeders. I followed the advice posted here and removed the reservoir. Wow, the gunk under there was amazing. Anyway, I used brake cleaner to clean it all out and fished out the gunk in the holes as best as I could.

The bad news now. The piston in the cylinder sticks. I tried pushing it back in manually and it released. As soon as I applied the brakes again, it stuck again. I'm sure there is gunk pushed down around the piston, I just need to know how to get the piston out so I can clean it up. Any ideas?

Thanks folks,

Jeff