77 front brakes nothing there

[Chadske]

I have a 77 xs650 new m/c and brake seals and line fluid is pumping through but the brakes aren't getting tighter... I've spent hours now and ready to just run a rear..

 

[Chadske]

I should mention that I have a clear tube going back into the brake fluid and I don't see any air bubbles going through it

 

[retiredgentleman]

I have a 77 xs650 new m/c and brake seals and line fluid is pumping through but the brakes aren't getting tighter... I've spent hours now and ready to just run a rear..

Have you taken the caliper apart and piston out, which you must have done if you changed the piston seals? Dirt and crud in the caliper is a common problem.

 

[Chadske]

Yes I cleaned all that out. I really don't want to have to pull the piston back out and risk ripping the seal..

 

[RFeng]

Pre-filling the break line with fluid before mounting it and bleeding made the job easy the last time I did my brakes.

 

[Chadske]

Plenty of fluid is flowing through. I have a clear line hooked to the nipple going back into the catainer. And i had the fluid pushed back into the bottle.

 

[RFeng]

Chadske - I think I saw the same thing when I was doing mine. Fluid was flowing, but little feel of pressure on the control. I figured I was just compressing air caught in the system, and the fluid was dribbling down the line past the air bubbles. That may be wrong - but that's what it seemed like. I removed the line, filled it and put it back on - a few pulls on the control later it was done. YMMV
Good luck!

 

[gggGary]

Forget bleeding for a bit, just pump the lever with the bleeder closed to build up pressure and move the piston out. Pull to the bar wait a second, release wait just a second, to the bar, repeat till it pumps up at least a bit hard, then go back to bleeding. Sounds like you haven't moved the piston so the pads are against the rotor yet.

 

[gggGary]

PS did you remove and clean BEHIND the seal? Before you replace the seal the piston should drop in and easily pull out of the caliper. With the seal in and lubed with a bit of brake fluid the piston should be an easy finger push in. And push it all the way in, That seem like it makes bleeding easier.

 

[angus67]

I find with bleeding brakes with empty line, I pump the handle ten times with the bleader closed, open bleeder, relieve pressure, do again....and again....and again.....
Some times there is no need for a full pump. You can get a lot of air out the mc with just a half pull.

 

[Chadske]

After hours finally got them. My problem is now when I tighten the caliper bolts all the way the brake is just froze on there but when I loosing them it's fine. Am I over tightening them? Thanks everyone..

 

[Chadske]

Should mention I went out and bought a syringe. Forced fluid in. Worked awesome. Next problem is drilling and tapping the banjo bolt hole.. But it off eBay and it only catches maybe 3 threads on the bottom...

 

[angus67]

take the sliders out and clean out the gunk. Re lube with axle grease. Just a little. Don't want any getting to your break pads.

 

[Chadske]

i will give that a go after work tomorrow. So I'm right by having the caliper all the way to the forks correct ? Thanks

 

[angus67]

well....once its all bolted down, it is were its going to be/ My guesse is the sliders. Don't go crazy with the grease. There is slider grease you can get at most auto stores. I think it just has a higher drop point, im not sure what that means, but I think it has something to do with melting/running out when its warm. I use marine bearing grease. Ive used it for my head bearing conversion, and the sliders on all my cars and cycles.