Bought my 95 TT250R Raid about month ago and after few days of use i have realised that over longer journeys with medium/hard front braking my front calliper gets very hot and start dragging
So i have took the front calliper apart and cleaned the seals(they were very dirty) and the groves where the seals seat , also put new brake fluid and fitted calliper back and still having the same problem
After few miles where i have used the front brake , front brake lever will get harder and start dragging till will block the front wheel so i cant go anywhere
One way to unlock the front wheel is to release the bit of brake fluid from bleeder or banjo bolt near the brake pump or to wait till cools down
Not a nice job fitting those brake pistons As Martyn says check there is no built up ''crud'' inside the piston sleeve & pins. I like to use rubber grease on the pins & rubber boots.
It also could have an airlock problem. Try bleeding from master cylinder,Then banjo bolt....Then bleed nipple.
Another thing is whether or not the correct brake fluid was used ??
.......................
Jarrah.
-- Edited by barra8 on Monday 3rd of December 2012 10:44:32 AM
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Your brake symptoms seem to be the classic problem of the brake lever touching or "bouncing" on the handguard. Had this quite a few times. Difficult to diagnose if you haven't seen it before.
If you haven't got wrap-around handguards fitted then its back to the drawing board!
I would check and make sure that the caliper moves freely on the pins. The pins should be greased and covered with their rubber boots. ALSO - check that the pistons are moving freely - a bit of crud may be preventing their return. Martyn
sounds like a caliper piston is sticking, causing excess heat to build resulting in boiling the fluid in the caliper. a caliper rebuild will be necessary in the near future
Ok, this may sound daft, but simple things first...
Is the bolt adjusted correctly on the lever? It shouldnt butt up tight on the piston at the master cylinder, needs a little play to allow for expansion.
Ok, this may sound daft, but simple things first...
Is the bolt adjusted correctly on the lever? It shouldnt butt up tight on the piston at the master cylinder, needs a little play to allow for expansion.
And is the spring behind the lever fitted and working as it should?
I was thinking that standard motorcycle brake fluid will do ?
thanks
Peter
It has been awhile since i have used the standard master cylinder so best way to know what brake fluid is to check on the filler cap. If it says dot 3 use dot 3....If it says dot 4 use dot 4.
I use dot 4 for my oversize master cylinder.
.........................
Jarrah.
__________________
YAMAHA ROCKS!!!!!!
TTR250ACTIVE''BORED'' ADDICT!
Favourite quote: To be old & wise first you must be young & dumb!
My own: Your never too young to learn an old trick! :)
Today i have re done everything changed one of the brackets pins as the old one was slightly pitted
And used old original master cylinder with lever adjustment
I must say it is much better but got to leave more than little play on lever so when the pressure builds up i have very sharp front brakes but not dragging
i had lots of bikes in my live and never had a problem like that and i never knew about expansion either
For a time being i will live this like that but will look for new brake set from younger bike in a future
Ok, this may sound daft, but simple things first...
Is the bolt adjusted correctly on the lever? It shouldnt butt up tight on the piston at the master cylinder, needs a little play to allow for expansion.
And is the spring behind the lever fitted and working as it should?
If all else fails, an issue we have with Land Rover Discovery brakes binding on is the flexi brake pipes breaking up internally creating a 1 way valve. You wouldn't believe there would be enough flow (or return) to do it but I can assure you it happens, and it's a bit embarassing to tell the client you've replaced calipers, sliders, pads, master cylinder AND ABS modulator (£1400, ouch) to no avail, then as a last resort put on 2 new £14 brake hoses and bingo...
this is very fascinating.. I think mossproof may be on the right track.
my thoughts are that the symptoms presented are the symptoms of pressure not being released from the line. ok, that pressure may be caused by pad/caliper issues causing overheating, or maybe just (initially) by the pressure of simply using the brake. but the question is why is it not being released? the master cylinder piston should retreat after lever pressure is released and expose the little hole in the hydraulic return circuit, and (unless the master cylinder reservoir was totally overfilled and had no air space) the fluid should return.
so normally you would assume that either the lever was not actually being released (unlikely if free play exists), or the master cylinder had a problem - eg (also unlikely) the internal return spring not pushing the cylinder back or it jamming, or something clogging the return hole. But you had the same problem with two different master cylinders!
so maybe the brake line is full of crud which is somehow floating up and blocking the master cylinder return circuit. perhaps this could be because the line is internally breaking up, maybe because the previous owner put some totally inappropriate fluid in there one time, or maybe the line is just old?
so the solution (if this happened to actually be the case) might be to clean out the whole system a couple of times, and/or get a new brake hose.
this is very fascinating.. I think mossproof may be on the right track.
my thoughts are that the symptoms presented are the symptoms of pressure not being released from the line. ok, that pressure may be caused by pad/caliper issues causing overheating, or maybe just (initially) by the pressure of simply using the brake. but the question is why is it not being released? the master cylinder piston should retreat after lever pressure is released and expose the little hole in the hydraulic return circuit, and (unless the master cylinder reservoir was totally overfilled and had no air space) the fluid should return.
so normally you would assume that either the lever was not actually being released (unlikely if free play exists), or the master cylinder had a problem - eg (also unlikely) the internal return spring not pushing the cylinder back or it jamming, or something clogging the return hole. But you had the same problem with two different master cylinders!
so maybe the brake line is full of crud which is somehow floating up and blocking the master cylinder return circuit. perhaps this could be because the line is internally breaking up, maybe because the previous owner put some totally inappropriate fluid in there one time, or maybe the line is just old?
so the solution (if this happened to actually be the case) might be to clean out the whole system a couple of times, and/or get a new brake hose.
Hi there
i was thinking about that and will buy complete set from other younger bike and see where the problem is
For a time being will have to live with that as is i useable condition