Just bled my front and rear brakes as there was too much movement of the levers before biting the rotor.
The front brake is now awesome, biting really nicely without too much lever pull.
The rear one is a different story, bled it 3 times and i am certain there is no air in it, yet the lever needs to be back to the bars before the pads bite the rotor.
I'm pretty sure i had this issue before with the front brake and shimano replaced it under warranty though i dont know if its the caliper or the lever at fault.
Warranty has expired so i want to spend as little as possible resolving.
What do you reckon, buy new caliper and try it (£35) or by the lever/caliper/hose (£55) to be certain?
Swap the levers over. That'll show what's wrong. Probably need a bleed after but you've practiced that.
Have you tried the old 'pop out the wheel, pull lever, put wheel back in' trick? That's a known solution for intermittent bite-point issues on new-ish Shimano brakes. I say 'known solution', it's worked for me and a few friends. Actually, if you've the wheel off you could see if it's slow pistons on the pad side or lever action.
Hi swamptin, yes i have tried that thanks.
Its odd, the lever action moves the pads as soon as you pull it, but it seems to take longer for the the pads to close to the rotor.
The bite point screw is fully in too.
Not bled properly? Make sure the pads are all the way back before starting in case there is some air trapped behind the piston.
FWIW, I overfill my XTR970 brakes because I like the bite point way, way out. That means bleeding, then squeezing the lever to move the pads in a little (I made up a thinner version of the yellow spacer) and then topping up.
I've had problems bleeding the rear in the past. I had to take it off the bike and hold it up so that the cable is vertical. It was only that way I could get ride of air bubbles out of the long flow of cable. Sounds mad but that's what was happening.
Try the '5 minute bubble bleed' on pinkbike. Sorted a similar situation for me.
Have a look at how this guy bleeds shimano brakes, very thorough.
Have you tried rotating the little bite point wheel thingy at the inboard end of the lever? Clockwise turn should increase the bite point with less lever travel.
Have you pumped the brake lever 10+ times?
Try putting more fluid in from the caliper end, it won't need a lot. This seems to work for me.