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Hi to all, a little technical help required. My son has an aprilia rs 50, with a dodggy front brke. Took the caliper off to check pads and workings. All seemed to be okay except for dirt. Problem is putting back together they wont work. Have bled and bled but just not getting any movement. Any suggestions, or is it a case of new calipers? HELP.

I've heard the mityvac is the best/easiest way to bleed brakes, but I've always done it the old fashion way.

Make sure the reservoir is full of fluid and cover it with the diaphram. Pump the brake caliper about 5 times and hold it in (important to hold it in so air is not introduced into the system). Open the bleeder screw and close it when the fluid stops coming out. Repeat the process. When I had to do it about a month ago it took about 10 times of that process until pressure finally built up. Also remember to check the fluid in the master cylinder, you don't want it going empty or it will suck in air and you'll have to do it all over again.

You can also try to wrap the bleeder screw in some teflon tape because some air can get into the lines that way too.

Hey thanks friend Sharp***(?)

Have tried all the pumping and bleeding and filling. No joy. Pistonm is not siezed but a little rust around exposed part. However, will buy more brake fluid and give it another go on the morrow. 1-undo bleed nip 2-pump lever until liquid is free from air, 3- with lever still pulled, tighten nip. ?????? Sound right?? anyway, bedtime in blighty. Cheers

Don't pump the lever with the bleedscrew open. That will always suck air back in.

Pump up the lever and HOLD it in. Keep holding it. Open the bleedscrew slightly and let the pressure bleed off. Your still holding the lever in, right? Good. Close the bleedscrew tight. Release the brake lever.

Do that over and over until you get clear, air-free fluid coming out of the bleeder.

OKAY, sorted. Brake now works again. Thanks very much for help. It is a ltlle different to bleeding a car, with a car you pump with bleed screw open. All I need now is someone to tell me how to ride a v twin with its engine braking. Totally can't get used to it.