Rear brake bleeding

[JetDriver]

I bled the front brakes; all is well.  I opened up the bleeder valve on the rear and all the vacuum pump got was air!  I played with that a little bit, then decided to pump the reservoir empty with the pedal.  So far, so good.  I then filled the reservoir with fresh fluid and tried to use the pump again and got nothing but air.  I then tried the pedal again, and now it does nothing.  The pedal moves alright, but the brake fluid doesn't go down in the reservoir.  Now what?  Is my master cylinder shot?

[Valker]

I'm betting there is an opening in the line. This opening may be in the bike's brake line or in the vacuum pump line. Put your finger over the vacuum pump line and see if it will pull a vacuum with your finger covering the end.
If you had rear brakes before you started, the master cylinder is likely good. Again, it sounds like a simple air leak.

[JetDriver]

I think you're right Valker.  I think my tube on the bleeder valve was leaking- sure did seem tight.  Why doing it the "old" way, pumping the pedal, didn't work, I don't know.  Baffling    All's okay now.  Thanks.

[mello dude]

Cant say specifically what is going on with you rear system, but lots of people make the mistake of over-pumping the pedal/lever when they bleed the brakes. If you over travel on the master cylinder, you can get brake fluid on the back side of the piston and then your hosed. You have to take the mc apart and clean it out, then reassemble. Hope you didnt do that......I usually tape a wood block on the front grip and just be extra careful on the rear not to over pump the thing.

Btw - convert over to speed bleeders makes the whole brake bleeding thing painless. 

[Valker]

I think you're right Valker.  I think my tube on the bleeder valve was leaking- sure did seem tight.  Why doing it the "old" way, pumping the pedal, didn't work, I don't know.  Baffling    All's okay now.  Thanks.

When there's an air leak like that, it doesn't matter if you use the pedal or not, it's just moving air then.

[JetDriver]

Cant say specifically what is going on with you rear system, but lots of people make the mistake of over-pumping the pedal/lever when they bleed the brakes. If you over travel on the master cylinder, you can get brake fluid on the back side of the piston and then your hosed. You have to take the mc apart and clean it out, then reassemble. Hope you didnt do that......I usually tape a wood block on the front grip and just be extra careful on the rear not to over pump the thing.

Btw - convert over to speed bleeders makes the whole brake bleeding thing painless. 

I think I dodged a bullet on this one- At first, I just pushed the pedal normal travel, before I was done I was pushing it down as far as it would go.  I think it's ok though.

[lew l]

I just bought "speedbleeders" for both bikes. I had them on my ZX-11 and changing fluids and general brake/clutch bleeding was easy as pie... no... cupcakes..... no..... cookie.....now fruit ( now that I'm diabetic )

[Pluggy]

Hey Lew and guys.  The speed bleeders come with a good coating of sealant around the threads, and that's one reason they work well.  I also have the vacuum pump. If the threads on the bleed valve are not sealing tight, you can be pulling a vacuum on.... nothing.  The experts say teflon tape or plumber's putty is a good sealer for this.  I'll take the tape. 

My first choice is that speed bleeder.  Nothing is easier.

[lew l]

Yesterday I installed Speedbleeders on both the Valk and the V-Max. Flushed both front and rear systems and even did the clutch on the Max in about 2 hours with only one mistake. Yes I let air into the system but got it out and all is perfect. The Speedbleeders are just great.
           Lew