So my 04 F4i has a dangerous problem. When I first start riding I have OK front brake lever pressure. The more I ride the pressue increases till the pads are rubbing on the rotors to the point of stopping the bike. If I wait the pads cool and release enough for me to get the bike home. When swollen I notice brake fluid pressing past the caliper seals and leaking. i rebuilt the master cylinder, replaced the pads, and replaced the brake fluid and this did not fix the problem. Any ideas?

 

If there was fluid leaking past the caliper seals, they are blown. Did you replace the caliper seals?

Is it both calipers clamping on the rotors, or just one?

 

The right caliper was definetly leaking. Should I just replace the right seals and test it or would it be smart to rebuild both?

Anyone know of a good place to order new seal from? only place I have found so far is cheapcycleparts and I am not fond of that company.

 

Since you'll be bleeding the brakes anyway, do both sides and have the piece of mind your brakes are good to go. A second set of seals for the other side won't cost very much more and you'll already be dirty anyway. Just my $.02

 

Have you changed levers? Knock-offs sometimes prevent the plunger from allowing the fluid to return and subsequently heats up and applies the brakes. Seen it several times.

 

^Good point

I have had it happen on an old water buffalo. It was years ago but as I remember somewhat, I think the pads were in opposite from where they should have been. In other words I think there was an inboard and an out board pad for each caliper.

Are you sure that the pads are fully seated or that the pistons move freely?

 

Yes I did change the levers a while back after the bike fell over and broke the lever off. Do you have any recomendations for a decent brand lever?

 

If it started right after the lever change, that would be my first guess.

OEM, Pazzo, ASV, CRG.

 

I think this is it too.

 

Can you explain exactly what you mean by knock offs?