I recently got some Vesra SRJL pads for my 07 750, and I'm noticing quite a bit of drag on the rotors with the new pads. I made sure to compress the pistons to allow room for the rotor to fit in and for the pistons to properly accommodate the additional pad thickness. It's to the point where when the front end is up on the stand, the front wheel only turns when I apply pressure. I thought this would be only temporary, but even after a track weekend the pads are still dragging; a simple ride around the neighborhood yields extremely warm rotors. I was talking with one of the local mechanics/racers, and he mentioned that he had noticed a similar problem on other GSX-R's, and thinks he has narrowed it down to actually being the master cylinder. My question is has anyone else had a similar problem? Any way to remedy this (without an expensive m/c) so I don't end up warping my rotors from a lot of heat building up?
some steps that may cure the prob... - make sure the preload is the same on each fork. - remove the wheel and install the axle. it should turn freely by hand. any binding, loosen one of the fork tubes in the triple clamps and adjust it up or down until you can turn the axle freely. the fork should only have to move half a mm or so. - ensuring pistons are clean using brake fluid, <you may want to push them out farther >, remove m/c reservoir cover and push the pistons back into the calipers. watch that brake fluid does not overflow the reservoir. you may then clean any excess fluid from the pistons/calipers using a cleaner on a rag. don't hose the things down. - remount all assemblys. do not over tighten the axle or axle pinch bolts. short-stroke the brake lever to push the pistons back out. the theory is, short stroking the push on the pistons allows the seals to recover...pushing them out with full strokes may distort the seals which defeats their ability to retract the pistons. watch that you keep fluid in the reservoir...don't want to suck air. - after you get a firm lever, do not fill the reservoir to max. those pads are awesome, btw. you'll get used to the initial grab and any further application of pressure on the lever after you reach what you think is max will result in an endo.
Awesome, I'll try those tips out and wrench on the bike tonight. One question, what do you mean by short stroking? Just a half-stroke of the brake lever? And yeah, the pads were insane the weekend I tried them out.
shorter, maybe. depends on when the pistons actually start to move. keep an eye on things. try not to push the pistons farther than 1-2mm per stroke. a full stroke could roll the seal in its seat. once you get the right stroke, you can pull the lever in quick succession. spinning the wheel as you continue will tell you when you've hit home.
Ended up having a slight misadventure with one of the pots, but the system is completely bled and the lever feel is way better than before. Rear wheel was in the air before I even realized Thanks for the tips!
