I recently had my 1984 Honda Magna apart for some work. Upon putting things back together I found excessive drag in the front brakes. On the test ride the front brakes locked up completely. When applying the brake lever the pressure seems to build in the lines and not release. After a few squezees their is so much pressure that the brake lever will no longer move. I have had both calipers professionally cleaned and the problem persists.
2007-08-31 16:23:04 · 7 answers · asked by Anonymous in Cars & Transportation ➔ Motorcycles
If the pressure builds in the lines it is NOT the calipers. Pull apart and clean your master cylinder. The valve inside is sticking. Flush your system and replace the fluid with new. Even if you already did it. The crap stuck in the master may come loose and cause the problem again. BTW, hoses are recommended to be changed when they get to be ten years old. You may want to do that at the same time. It'll make it easier to know that everything is clean inside.
2007-09-04 10:35:13 · answer #1 · answered by Firecracker . 7 · 0⤊ 0⤋
replace your brake hose.
vehicle brake hoses are dual layer rubber or poly.
sometimes the outside will look fine and the inside will be dry rotted, a small flap of rotted rubber will peel up and block fluid from traveling one direction mostly to the caliper, but it is also common to see it the other direction too.
braided hoses have this problem too.
there are a couple of other things that cause this as well, but this is by far the most common on motorcycles and scooters.
(the other things that can cause this are: caliper piston out of true; master cylinder has a blockage; general dirt in the brake system)
2007-09-02 19:31:34 · answer #2 · answered by godz68impala 3 · 0⤊ 0⤋
99 times out of 100 the problem with sticking brakes is the piston/s in the calipher (rust and/or gummed up) and is a simple cleaning job. However, from what you describe I suspect the return hole in the master cyinder is plugged. In the bottom of the resevior there are two holes, one is usually about 1/8 inch diameter, the other is very very small and is easy plugged up and I'd wager that is your problem. I don't know what type master cylinder you have, but, in the rectangular metal ones the holes are usually easy to get to. The ones with the round plastic reseviors are more difficult because you have to remove two screws in the bottom and pry the resevoir out of the master cylinder to access the holes.
Once you see the small hole you can unplug it with the bristle yanked from a wire brush or wire wheel on a bench grinder as they are small and stiff (guitar string might work also).
2007-08-31 17:30:55 · answer #3 · answered by G B 6 · 3⤊ 0⤋
Who ever cleaned them did not do a good job,
The pistons need to be cleaned and re- O-ringed. the caliper has a series of ports or pathways that need to be cleaned and cleared, from what you write this was not done.
Take the bike back or get your money back and have someone who knows what they are doing ,do the job right.
2007-08-31 16:37:36 · answer #4 · answered by Anonymous · 3⤊ 0⤋
I'd also have a look at your brake lines if they are originals it has been known for the inner to collapse the pipe and not allow fluid to release. Might be worth investing braided hoses.
2007-08-31 23:40:48 · answer #5 · answered by motomarco9999 2 · 1⤊ 1⤋
Bring it to another shop, they obviously don't know what they're doing.
Gunk builds up under the o-rings and force them against the pistons, not allowing then to return.
The o-rings have to be removed and the gunk scraped out.
Sometimes they're not repairable and have to be replaced.
2007-09-01 07:04:30 · answer #6 · answered by guardrailjim 7 · 1⤊ 0⤋
they did the job halfassed, and they need to do it over. take it back and have them do it over. or, get a service manual and do it urself.
2007-09-01 05:00:46 · answer #7 · answered by forktail_devil 5 · 0⤊ 0⤋