[mut]

This is probably a very basic issue but I don't think I am doing it right. I just rebuilt the front brake on my CB750K5. I have a new piston and seal with new calipers. I filled the master cylinder and pumped the brake, then loosened the bleeder valve until some fluid came out, then tightened the bleeder valve with the brake lever pulled in. I repeated this process and filled the reservoir again.

I still have a bunch of play in the brake lever. All in all it works much better but it is by no means tight. It is not at all like my MX disk.

Am I bleeding the air correctly?

Thanks, again.

Mut

 

[Judeyramone]

Hardly the definitive answer, but I've always heard that you should put a hose on the bleeder, and the other end in a container of brake fluid. Then you pump the brakes until no air comes out. The hose in brake fluid ensures that the only thing getting sucked back into the system is more brake fluid. That's how I've always done it.

 

[oldschoolorange]

I am lazy so I always gravity bleed mine first, just crack the bleeder screw and let the fluid drain for a few mins. then go with the pressure bleed method. You can allways get one of these http://www.speedbleeder.com/

 

[imslow]

what judey said

 

[FR]

I finally purchased a vacuum pump, primarily for bleeding brakes. You just put the hose on the bleeder screw and open the bleeder while under vacuum. It works very well.
The pump was a little more money than I had planned ($50), but now I have it and the time it saves is well worth it.


FR

 

[joe c]

and if youve drained the system, it can take a very VERY long time.


jc

 

[Geeto67]

If I have drained the system it usually takes me like 3 or 4 times of full bleeding and letting it settle and such to get full brake pressure.

If you think it might be a problem get a high E guitar string and stick it in the holes in the MC (both the drain and the return).

 

[KeninIowa]

What Judey and Geeto said. Run it into a container and it still takes time on a dry system. One thing I do is to slowly pull in the lever with the cap off and keep it pulled until the air bubbles stop coming out the MC. You can get alot of the air out the top, sort of a poor man's air-free banjo. Most people stroke the lever too fast. They aeriate the fluid making the few big bubbles a zillion tiny ones. And like Geeto said time is your friend. A lot of times if I'm not in a hurry, I'll fill the MC and just let it sit, give the lever a couple af squeezes as I walk by it during the day. Then when you go to do the final bleeding it's cake. Last time I had the brakes apart on my Chevelle they air locked. We dicked around forever trying to get them to bleed, got pissed, went home, next morning had brakes.

I have a Mityvac. It's a lifesaver when you really need it, most of the time it's a PITA. One thing on that is always Teflon tape the bleeder threads. A lot of times you'll pull air past them and you'll wonder why you can't ever get the bubbles to quit. I think it says that in the instructions if you know anyone that ever reads those.