*trix*

Ok so heres the story its a little bit of a doosey, but I will try to simplify it. I had to take the master off to put dirt bars on my 636. I put them on and got one extended line and used a banjo I had in my toolbox. I then went and bleed the brakes with a pump and went to take it for a ride. After about a mile of rideing on and off the front brake it began to lock up on me and I couldnt even push the brake in it was so hard and it locked up my front wheel. I assumed it was the line so I went back and got a new line, the new line did the same thing. I went back to completely stock (stock bars/stock lines) and took the bike for a ride and it still locked back up. I now took the master apart and i see some chaffing and ware on the inside. But now where do i go from this do you think it was the master locking up or do you think that its my calipers locking up

old man roger

if the return port on your master was clogged with dirt or some thing that can cause it or if you over filled the res that can cause it , some times over filling the res will not leave any room for the hot fluid to expand and when that happens it causes the pads to not completely release so they will create more heat as you ride and that will cause the fluid to expand more and create more pressure...there is a full line on the res for a reason ...

if it's just a cloged return in the master you can just clean it out , when the master is off the bike and empty you should be able to blow into the res and hear the air coming out of the banjo hole and visa virsa ....

if you can't hear air and the port is clean then you may need to file the pin that pushes the plunger in the master , i will find the thread that describes this hold on

old man roger

https://www.stuntlife.com/forums/444...dials-hbs.html

crashtest 750

You might also have air in the line. When the brakes get hot the air expands and causes the brake to lock up. That is why that it locks up when hot but not when cold. With as small as the master is you almost have to get every bit of air out.
I usually gravity bleed then power bleed my brakes after that.

*trix*

ok i have had the res overfilled cause it sits on a slight angle i guess i have to get it angled straight and fill it only to the needed level. I'm gonna clean it out today put it all back together pump it out and take it for another ride and see what happens.

*trix*

and thank you guys for the help so far i will keep yu posted on whats going on

Trachito

post an update to see if it worked.

Towlieee

sounds like you got **** mixed up man


air compresses, fluid does not..

You MUST have air or the pressure has no where to go..

old man roger

but both expand when heated

*trix*

i also had just called a motorcycle repair shop and he said "you can never have to much fluid" .....yeah

old man roger

don't ask that guy any thing ever again

*trix*

also do you think it could be that i still have air in the lines cause that wouldnt make any sense either when i bleed it and it acts as if theres no air left and theres only fluid when im bleeding it and i have good pressure

*trix*

and it also only does it when im riding not when im not moving it wont build up pressure even if i pump it for like 5 mins but in 5 mins of riding its rock hard

old man roger

with out bleeding it my self i couldn't say

i suspect the heat building up while your riding is the issue

*trix*

Nah I know that the lines are clear 100% cause im using a pump that only has fluid in the lines and I open the bottom bleeders and get everything out, but the heat building up has to be it in some case weather it be air or the fluid not getting back up to the resivoir because of a poor decision i made by overfilling it. I am gonna clean everything out and put it back together and bleed it again, and see what happens. Also i use valvoline dot4 synthetic brake fluid is that fine? or am i incorrect in saying that?

old man roger

thats fine

*trix*

WORD

*trix*

ok so here is the update. I finally gave up after trying everything that everyone had told me and I went to someone (and I ******* hate going to people for anything cause I alwaysdo **** myself). After him trying everything I had tried we finally came to the conclusion that the brake lever itself wasnt letting the piston come far enough out to loose pressure when letting the fluid back to the resivoir. So we took the pin out that pushes in on the piston inside of the master and shaved off about a half an inch and Voila my brake is stronger then it ever has been, and its not locking up on me at all. Thanks OMR and everyone else who PM'ed me for throwing in their 2 cents to help me out.

old man roger

post # 2 in this thread

*trix*

well it didnt make sense to me that i changed nothing about the brakes in reality that I would have to file it but it just gos to show i should listen to you guys more often