Hitchcocks Forum

I've fitted a braided stainless line to my disc brake, but I can't get the air out of the system. I'm using a non-return valve device on the nipple, and I've stood there pumping the lever for ages without anything much coming out of the nipple or any resistance on the lever. The level in the reservoir has gone down a bit so I must be getting somewhere, but I don't remember it being this difficult many years ago when I last did it!

John.

I take it that this one of the RE disc brakes possibly with the Pricol caliper.

If so I had exactly the same problem and the only way is to "reverse bleed" it, i.e. open the bleed nipple and force fluid in through the nipple.

If you do that you wil find all the air bleeds out through the reservoir in no time and you have a really good brake.

I reverse bled mine by finding a piece of tube that was a tight fit over the bleed nipple, filling the tube with brake fluid and then blowing down the tube (you have to blow bloody hard) and opening the bleed nipple between breaths.

As I say hard to blow but it works.

Good luck

Thanks! I will try that. Surely you mean "close the nipple between breaths"?

Yes - CLOSE the nipple between breaths !

Hi John. I asked the local vets for a large syringe... attached to bleed using the battery vent tube..
Pull on the syringe and the vacumn will draw the brake fluid through...

Failing that fill the syringe and pump it back up the system... gwilly

Yes, the idea of a syringe occurred to me. Vets is a good idea.

I don't know if it will work with a Bullet but on many bikes the easiest way to bleed the front brake is to hold the brake lever tight against the handlebar using a strong rubber band and leave it for a few hours - overnight is fine and hey presto all the sir comes back up through the master cylinder with no effort(needless to say you do not open the bleed nipple!!)
Hope it helps
Dave

As Valsp suggests fastening the brake lever back ,sometimes overnight does the trick because the air lock is actually at the reservoir end of the system or you can fill an oil can with brake fluid and use this to push fluid back up the system through the bleed nipple rather than relying on lung power

I have found that by removing the banjo from the master cylinder(after covering everything with a sheet so brake fluid doesn't get on the painted bits)squeeze the brake lever, put your finger over the banjo hole and let the lever go, repeat this a couple of times and you have bled the mastercylinder so then refit the banjo and then you can bleed as normal. Only downside is often you need to fit new washers to the banjo but at least you can bleed the brakes