J
Jack Klarich
Guest
IMO Harley is having problems with the master cylinders, The MoCO wants the techs to stretch the spring and rebuild the master, I say replace it
Front Brake Loss
- Thread starter jonathan8186
- Start date
biscuit
Junior Member
What happens if you just grab the brake lever hard once?As in a panic stop.
Just grab it and dont let it go.Does it just come in an inch or so and stop?Feel normal?
Then what happens if you just slowly SQUEEZE it in?Will it come all the way in until it hits the twistgrip?If so,as predicted ,your piston seals are shot.Not good.
By suddenly grabbing the lever,you are forcing the seals to instantaneously expand against the M/Cyl. bore, thus preventing the fluid from flowing past the seal lips.When you squeeze it slowly,the lips aren't forced out and fluid can(and will) seep between the seals and the bore of the M/Cyl.Not good.
A very easy test that takes maybe 25 seconds:grab a handful;lever is hard.Squeeze gently;lever comes in all the way.Then rapidly pump lever and pressure will return to normal.Squeeze gently:lever will come in all the way again.Go directly to Seal kit.
This is a test to discover IF your seals are U/S ;and not to prove faulty brake bleeding.
Just grab it and dont let it go.Does it just come in an inch or so and stop?Feel normal?
Then what happens if you just slowly SQUEEZE it in?Will it come all the way in until it hits the twistgrip?If so,as predicted ,your piston seals are shot.Not good.
By suddenly grabbing the lever,you are forcing the seals to instantaneously expand against the M/Cyl. bore, thus preventing the fluid from flowing past the seal lips.When you squeeze it slowly,the lips aren't forced out and fluid can(and will) seep between the seals and the bore of the M/Cyl.Not good.
A very easy test that takes maybe 25 seconds:grab a handful;lever is hard.Squeeze gently;lever comes in all the way.Then rapidly pump lever and pressure will return to normal.Squeeze gently:lever will come in all the way again.Go directly to Seal kit.
This is a test to discover IF your seals are U/S ;and not to prove faulty brake bleeding.
jonathan8186
Member
This sounds crazy but I have tried that all operations are normal ultill I drive the bike for a few miles than the lever has to be pulled in more to apply brakes until there is no brake.
Operation works fine for the first mile then goes down hill from there. After bleeding the system with the bike setting in the garage you can move the lever fast and hard or slow it doesn't mater it fills just the same like it is work fine. I take the bike out for a test drive and it starts loosing the feel until there is no brake.
Last edited by a moderator:
jonathan8186
Member
Thanks for everyone who helped on this matter. I got it fixed with a rebuild kit from the local dealer. It was very easy to do took about 20 min.