no rear brakes, what do you guys think?

[Seth Matthews]

'80 Suzuki GS1000G

Today I was riding, had to stab the rear brake kind of hard, and lost my rear brakes. I don't see any signs of a broken line, pads look like they have a little left on them, but not much, and the reservoir cup has a little fluid left in it as well. Should I suspect the master cylinder or the pads themselves? Maybe the brake cylinder at the caliper? I can push the foot brake all the way to the exhaust pipe and not get any response from the brakes.

Luckily I still had my front brake and made it home safely lol

 

[brianinpa]

is any fluid coming through the brake line?

 

[Seth Matthews]

no, and another forum, the members are saying that i probably sucked air in the line since the fluid was so low, but that i really need to replace the entire system, front to back, and not just the fluid, lines, and pads. can I just flush it well after replacing the lines? the bike is an '80 model, and only has 19K miles on it even though the brake fluid is black as used oil. I really hate to spend a crap ton of money rebuilding the master cylinders and brake cylinders.

 

[AspectOne]

Bad master cyl.

 

[brianinpa]

Rebuilding a MC isn't that expensive. It's just a few O-rings and a little bit of time.

 

[steppenwolf]

On mine years ago before I went ss lines I had to clean the spoog holes due to the rubber breaking down and clogging the front master cyl so it didn't work.But if you are low on fluid,you have a small leak,it is a closed system.
If you keep having problems I will send you to a UJM site I belong to,small but knowledgeable with many Suz riders.

 

[Kynan C.]

I has a simular issue with my bike. Master cylinder kit and SS brake lines helped. Never has the issue again.

 

[Alan 63]

no, and another forum, the members are saying that i probably sucked air in the line since the fluid was so low, but that i really need to replace the entire system, front to back, and not just the fluid, lines, and pads. can I just flush it well after replacing the lines? the bike is an '80 model, and only has 19K miles on it even though the brake fluid is black as used oil. I really hate to spend a crap ton of money rebuilding the master cylinders and brake cylinders.

Go through the whole system , hoses had a lifespan of 4 years , dot 34...
Fluid has about a 2-3 year lifespan...
You already know the pads are low, if you do that and rebuild the calliper and master cylinder you will be amazed at the brakes you have

 

[GreggS]

There is a "step" or ridge on the rear pads that marks the wear point. It can be seen through the inspection port or looking from the rear of the caliper. Worn pads would allow the fluid level to also get low and during hard breaking, you may have pushed air into the system. Also there is an two part adjustment to the pedal. If it is bottoming against the exhaust, too much travel and need to be adjusted - again, a sign of worn pads. Rebuilding this isn't a financial big deal and not difficult, but must be done. There is plenty of aftermarket stuff available. In my opinion, OEM is better, but cost more. I would go to eBay and buy a Clymers manual for the bike. I have the same bike and rebuilt mine last year, but an early season inspection saw it coming.