GL1800Riders Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
59 Posts
Discussion Starter #1
My friend has a 95 Goldwing he is trying to sell, but is having brake problems. The rear brake locks up after he rides it. Ride, park, then brake locks up like it has a vacuum that sucks the brake closed. New caliper, new hose. :shrug: Any ideas??
 

·
Banned
Joined
·
11,396 Posts
My friend has a 95 Goldwing he is trying to sell, but is having brake problems. The rear brake locks up after he rides it. Ride, park, then brake locks up like it has a vacuum that sucks the brake closed. New caliper, new hose. :shrug: Any ideas??
It's possible that the rear hose can swell closed after it heats up.

How many miles on the bike?.
Was the brake fluid changed when it was supposed to be?.
Did he over fill the rear master reservoir w/brake fluid not allowing for expansion? (the fill line is there for a reason)
 

·
Registered
Joined
·
878 Posts
I see you stated "new caliper"... But was it indeed a new caliper or just a take-off from another bike.??? What you describe I have found to be caused by the caliper piston seals binding on the pistons... Often times there is corrosion that forms in the seal groove on the caliper... This causes the seal to squeeze tightly on the pistons and cause them to bind... You can remove the seals and clean the grooves out (scrape) real well and then put some caliper grease in there with new seals... The pistons should then slide back into the caliper easily by hand pressure alone... Also insure that bushings that allow the caliper to float are free and slide easily as well...
If the caliper replacement was indeed new, then I'd look at rebuilding the master cylinder (easy to rebuild, but a bear to remove and install)...
 

·
Registered
Joined
·
59 Posts
Discussion Starter #4
Yes, it's a brand new caliper and the rear brake line was replaced. You can ride and then stop. After the bike sits for 5 mins the wheel locks up and later it will release on its own... weird.
 

·
Registered
Joined
·
1,665 Posts
My friend has a 95 Goldwing he is trying to sell, but is having brake problems. The rear brake locks up after he rides it. Ride, park, then brake locks up like it has a vacuum that sucks the brake closed. New caliper, new hose. :shrug: Any ideas??
> Given that it's a Linked brake that the rear brake is a part of, then I'd also be looking at the Front Left Caliper too, to verify that it's not the source of the lock-up.

> I've heard of such lock-up happening from a Collapsed Rubber Brake Line... You say that the "Hose" was replaced, but does that mean the Entire Rear and Front (left) brake line, or just one of the rubber pieces?... Note that for the rear alone, there are Two rubber sections, one on each end of a metal hard line.

> I also seem to recall Chuck411(#?) having a similar problem on his 1800, due to a bad seal in the rear brake master cylinder.
 

·
Registered
Joined
·
1,665 Posts
...Also insure that bushings that allow the caliper to float are free and slide easily as well...
> Good point!... the Caliper should freely slide side-to-side, prior to application of the brake.
 

·
Registered
Joined
·
23 Posts
Had a problem like that once on my Gl1500. Found out the tiny pinhole in the bottom of the master cylinder was plugged up and not allowing fluid back from the caliper when the brake was released. I think heat build up caused fluid expansion and then when it cooled off the brake would work okay. Might be something to look at if no other cause can be found

Flatlander
 

·
Registered
Joined
·
1,665 Posts
Found this over in the General Forum... Says that a formerly Kinked brake line can cause same problem... In which case, you may have a bad front left brake line, which is not allowing fluid to return to the rear master cylinder.

http://gl1800riders.com/forums/showthread.php?t=285391
SSNCOB: "DO NOT CLIP, KINK OR OTHERWISE BEND THE LINE !!! The inner portion of a brake line is a small tube. If you put a bend or kink into the line, it will permanently deform the line and prevent brake fluid from coming out of your caliper piston when you take the high pressure from applying the brakes off. The pistons retract slightly from the rotor due to the slight irregularity in the rotor. This pressure is very small cmpared to the pressure when you apply the brakes. In essence, the kink acts like a one-way valve for your brake line, causing the caliper to stick and the rotor and brake pads to overheat and warp."
 

·
Registered
Joined
·
24,624 Posts
Had a problem like that once on my Gl1500. Found out the tiny pinhole in the bottom of the master cylinder was plugged up and not allowing fluid back from the caliper when the brake was released. I think heat build up caused fluid expansion and then when it cooled off the brake would work okay. Might be something to look at if no other cause can be found

Flatlander

I agree, that is exactly what it is. :thumbup:
 

·
Registered
Joined
·
59 Posts
Discussion Starter #11
Flatlander...OK so now I have this bike in my shop and I am wondering if you replaced the master cylinder or rebuilt it or just unplugged the hole?
 
1 - 11 of 11 Posts
Top