05-01-16, 11:47 PM
Hi NotAnotherHill,
Just a thought on sticking front disc brakes, especially as you cleaned and sorted them out after last outing.
I have a MR2 Spider (Yuk 4 wheels) and had exactly the same problem with the driver side front brake sticking as the car has done 80,000 mile I decided to do a complete overhaul of the brakes.
I fitted four new discs, new disc pads all round and replaced both the front calipers as the pistons were pitted, although the caliper was moving fine on the slider pins (Floating calipers)
Lubed up the slider pins with silicone grease, a smear of Copper slip between the pad shims and pads and on top of the shims where brake piston contact is. I thought that has to cure it, but Oh! no that brake was still binding to the point that it made the disc really hot and the pads on that wheel stank after about 5 miles.
I did an internet search and found a link that said one of the main causes of brakes binding on older vehicles is caused by the rubber on the inside of flexible brake pipes braking down with age, apparently the rubber can start to laminate on the inside of the pipe and a flap can block the oil/fluid way, when applying the brakes the pressure exerted by the master cylinder will force the lamination/flap of rubber out of the way but the rubber can be drawn back down as the brake fluid is drawn back to the master cylinder and block the pipe causing the brakes to stick. If you find the brake sticking after applying the brakes leave the bike for a couple of hours and try spinning the front wheel again if it spins fine then there is a real possibility that the problem is brake pipes braking down, as a jammed piston is a jammed piston and usually will not release itself.
Just a thought.
Good luck with sorting the problem out.
PS: I'm sure you already know but don't use mineral grease anywhere near the piston seals or other rubber brake parts, use silicone grease or red rubber grease this is on slider pins as well. Mineral will rot out the concertina rubbers and seals.
Just a thought on sticking front disc brakes, especially as you cleaned and sorted them out after last outing.
I have a MR2 Spider (Yuk 4 wheels) and had exactly the same problem with the driver side front brake sticking as the car has done 80,000 mile I decided to do a complete overhaul of the brakes.
I fitted four new discs, new disc pads all round and replaced both the front calipers as the pistons were pitted, although the caliper was moving fine on the slider pins (Floating calipers)
Lubed up the slider pins with silicone grease, a smear of Copper slip between the pad shims and pads and on top of the shims where brake piston contact is. I thought that has to cure it, but Oh! no that brake was still binding to the point that it made the disc really hot and the pads on that wheel stank after about 5 miles.
I did an internet search and found a link that said one of the main causes of brakes binding on older vehicles is caused by the rubber on the inside of flexible brake pipes braking down with age, apparently the rubber can start to laminate on the inside of the pipe and a flap can block the oil/fluid way, when applying the brakes the pressure exerted by the master cylinder will force the lamination/flap of rubber out of the way but the rubber can be drawn back down as the brake fluid is drawn back to the master cylinder and block the pipe causing the brakes to stick. If you find the brake sticking after applying the brakes leave the bike for a couple of hours and try spinning the front wheel again if it spins fine then there is a real possibility that the problem is brake pipes braking down, as a jammed piston is a jammed piston and usually will not release itself.
Just a thought.
Good luck with sorting the problem out.
PS: I'm sure you already know but don't use mineral grease anywhere near the piston seals or other rubber brake parts, use silicone grease or red rubber grease this is on slider pins as well. Mineral will rot out the concertina rubbers and seals.