Bleeding the back brake...

[Bigtrucknuts]

So Iv replaced the pads at the back. No problem 20 min job, done.
Brake lever was a bit soft but I thought just needs a bit of bedding in. A week later it's still soft so I thought maybe there is a little air in the fluid.

So started beading the brake as normal then the lever went very soft and no fluid is coming out the bleak nipple.

What's gone wrong ?

 

[AberdeenAngus]

Did you remember to top up the reservoir ?

 

[Bigtrucknuts]

Yes it was topped up at all times.

 

[Clifton]

I just changed brake fluid in the fronts on my GSA however looking at the rear caliper I noticed the brake line and bleed valve are not located anywhere near the top (when the caliper is attached). That seems like it would allow any bubbles to rise away from the bleed valve. I didn't have enough fluid anyway but when I do the rear I think I'll remove the caliper and turn it so the bleed valve is at the top.

 

[Bigtrucknuts]

It could be that internally the nipple is at the highest point of the fluid chamber. It doesn't seem likely that the only way to bleed the caliper is to remove it.

 

[peterh]

It doesn't seem likely that the only way to bleed the caliper is to remove it.

That was the trick on Aprilia Milles The bleed valve was on the bottom of the calliper, the master cylinder was very close to the exhaust pipe and the result was a rear brake that worked well for maybe 100 miles after bleeding before becoming almost useless. Still, just shutting the throttle gave impressive braking on the V twin mill.

 

[Deleted account 211025001]

Clifton may have hit the nail's head.

Use a pressure bleeder. After years of hit and miss brake bleeding I bought myself one and haven't looked back

Mytivac Linky

Andres

 

[Bigtrucknuts]

Ok I'll try one. There are two types of forced bleeders. Pressure and vacuum. The vacuum looks easier to use but one post I read said it could mess up the ABS unit by pulling its seals inside out.
Anyone used ether on an LC?

 

[MikeO]

You have ABS?

Are you using the correct procedure for bleeding ABS brakes?

 

[Bigtrucknuts]

Probably not given the problem iv got. The general consensus appeared to be bleed just as normal so I did.
That is the procedure for the LC?

 

[Bigtrucknuts]

No brake experts out there?

 

[Clifton]

Ultimately I would think a pressure bleeder might be the best.

I use a Mite Vac vacuum bleeder, it makes it so easy to suck almost an entire reservoir of fluid through the line at a time. But I always finish with a few pumps the conventional way with the lever or peddle. The reason is when the vac is sucking fluid, naturally the bleed valve is loosened to open, it sometimes brings some air around the threads and into the caliper. Usually any air right there turns and comes out in the form of tiny bubbles but sometimes a trace amount of air remains. So those last few conventional pumps pressure any remaining air out. But the bleed valve must be at the highest point for this to work even if it means unscrewing 2 caliper bolts to do so.

 

[Bigtrucknuts]

Just got of the phone to BMW Wolverhampton, very helpful.

You can just bleed the brake normally or manually as he put it or use a vacuum or pressure easy bleeder. Could be iv trapped some air somewhere so I'm going to buy a vacuum bleeder and give that a go.