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View Full Version : (Help) Brakes wont work!! Xs650



GoyaNator
05-14-2010, 1:39 PM
I need you brake gurus to please help me out, i have a 78-xs650 i have a springer on it with a brand new Dna/Ultima 4 piston caliper,new line, I cant get any pressure to the master cylinder,,im running out of ideas on how to get the fucker to work.

ive tried bleeding it the old fashioned way ,last nite tried a mighty vac and still no pressure

Would the M/C being from a jap bike not have enough power to push the caliper?

Ive tried the stock XS master and another one off of a old honda.

Please let me know anything that might get this thing to work,its the only thing holding me back from riding.

Thanks

mojo1272
05-14-2010, 5:56 PM
First, are you using the banjo bolt washer with the rubber center...if throw away and get the crush style, either copper or alum. Fill the master cyl and try to get pressure out of it first. With banjo bolt removed put your finger over the outlet tight and pump up the lever. Slowly release finger while holding the lever back. You should here the pressure and some fluid push out. Next hook up the brake line and do the same thing but this time hold your fingers around the lower banjo fitting that goes to calip. With the brakes pumped you should here some air pressure and maybe some fluid push out when slowly removing fingers. If you want to test calip...put some air to the inlet and see if the pads move and grap break rotor. If all this is good then Your just having a hard time getting the air out. Hook the system back up and try to pump the lever while tapping the brakeline with a wrench to see if you can get some air to bleed back thorugh the master cyl. You can also try bleeding it systematicly. First at the mc banjo bolt then the banjo fitting at the calip and finally at the calip bleeder. If none of this works then you my be bleeding air in somewhere...crack in mc or calip. I've seen them bleed air in but no fluid out...weird but I've seen it happen..Good Luck...
Mojo

tobiism
05-14-2010, 6:54 PM
More than likely its just not bled properly. I would use the reverse bleeding method, it works for me EVERY SINGLE TIME.
Use a large plastic syringe with a small hose attached to the bleeder screw on the syringe.
Take the cover off of the reservoir and remove almost all of the brake fluid.
With the syringe full of brake fluid, push it through the bleed screw, into the caliper and up the line into the reservoir. Lay a towel over the open reservoir so fluid doesn't squirt 8 feet out onto everything you own.
Once the reservoir is full you should have good brake pressure.
Keep in mind, your new caliper has more swept area of brake pad than your original system would have had, so you will not have the same "feel" in your master cylinder as you would have with the stock system.

GoyaNator
05-14-2010, 8:03 PM
thanks for the help guys ,ill try all those methods ,,but would the stock master cylinder or one off of an older honda be too weak to power the 4 piston caliper?those are the two ive been trying to use , or should i find something else to push that caliper?

tobiism
05-15-2010, 9:24 AM
Use the one you've got, see how you like it, it'll probably work fine.

jamesgs4
05-15-2010, 2:53 PM
thanks for the help guys ,ill try all those methods ,,but would the stock master cylinder or one off of an older honda be too weak to power the 4 piston caliper?those are the two ive been trying to use , or should i find something else to push that caliper?

well you amy be right on the master cylinder issue, the stock one may just not move enough fluid to operate the 4 piston caliper.