Hi there,

I've done a few bits to my daughters GasGas - bought off the internet...never again.

I've not had much luck getting the front brake to do it's job.

It worked when first bought, but not very weell, so I replaced the very worn pads and flushed it throuough with fresh Dot4.

Still the same, the lever comes back to the bars with a bit of effort, giving enough pressure to slowly stop the bike.

I even bled them through last night from the banjo union bleed nipple using the Gasgas video recommended method with a syringe, but still no difference.

Would i be right in saying that I need to strip the M/C and replace the seals ?

Any help/advice would be appreciated.

Cheers,

Ewan.

You could take the piston/seals out and inspect them,if it looks worn,you can replace them for a tenner.Might be a good place to start.

Just incase - have you bled properly?i.e. pumping the lever untill no more air bubbles come out of the master cylinder. Leave the top off when doing this.

also have you adjusted the little adjuster at the foot of the lever, sounds like you have to push it in a bit

also is the disk clean, had the same problem with my sherco after weeks i discovred that it was a little drop of grees to blame

Edited April 29, 200818 yr by johnkennedy

Hi there,

I've done a few bits to my daughters GasGas - bought off the internet...never again.

I've not had much luck getting the front brake to do it's job.

It worked when first bought, but not very weell, so I replaced the very worn pads and flushed it throuough with fresh Dot4.

Still the same, the lever comes back to the bars with a bit of effort, giving enough pressure to slowly stop the bike.

I even bled them through last night from the banjo union bleed nipple using the Gasgas video recommended method with a syringe, but still no difference.

Would i be right in saying that I need to strip the M/C and replace the seals ?

Any help/advice would be appreciated.

Cheers,

Ewan.

Ewan,

Make sure the lever is adjusted far enough out, comfortably for her of course, so that when she pulls in the lever the piston has enough throw to be effective. The master cylinders only move a small volume of fluid and if the lever starts too close to the bar, it will not pressurize the system properly (the clutch is more sensitive to the lever starting in too far but I've seen it with brakes). The adjustment screw on the lever has to have a little clearance where it meets the plunger rod that pushes on the piston. Take the rubber boot off the M/C and check that the piston retracts back to the stop at the circlip or the piston return spring may be weak. If the rubber boot has broken and let in grit, you'll probably need to use a rebuild kit for the M/C. The front brake is probably the easiest to bleed air from, so I'm guessing that, after checking the adjustments, you'll probably need to rebuild the M/C.

Jon

I'm With JK on this one. The Brake "self bleeds" until the sir is all out. To Check take the lid off the resivoir and press the lever. You should have a "splurt" back. If you don't keep pressing and releasing until you do.