Bleeding front brake

Bigtiddle · Post by **Bigtiddle** » Sat Sep 24, 2011 7:49 pm

Hello,
I have fitted a Renthal bar conversion from http://www.topyokes.com which went well. The kit included new, longer braided brake and clutch hoses. The brake hoses are 2 lengths, one from the master cylinder to the right hand caliper, the other (using a piggyback banjo bolt) goes from the right to the left caliper.

I have tried all ways to bleed the front brake but cannot get any feel or pressure at the lever at all. I have even taken the master cylinder to the local gealer and had a new seal kit fitted but I still can't get anything at the lever,

Does anyone have any magic tricks to fix this and help a newbie?

Kev L · Post by **Kev L** » Sat Sep 24, 2011 8:50 pm

Where are you based mate? If you can borrow a vacuum pump it will make it easier for you.

lloydie · Post by **lloydie** » Sat Sep 24, 2011 9:37 pm

Try back filling it with a syringe
Undo the master cylinder banjo bolt and back fill the piggie by connecting the string to the bleed nipple you will need to loosen this also first then the other one until it comes out the top buy the master then tighten
That should give you enough pressure to bleed normally

Can't ride but it don't stop me trying

Bigtiddle · Post by **Bigtiddle** » Sat Sep 24, 2011 9:40 pm

Thanks for the replies so far. I'm based just outside Norwich in Norfolk.

Stratman · Post by **Stratman** » Sat Sep 24, 2011 9:54 pm

A vacuum pump or syringe will do it more easily, but if you persevere with the "usual" method it will get firmer. Eventually. And I mean, after a lot of pumping, but it will get there. Helps also if you tilt the bike/bars to shift any air resting in the master cylinder.

Miztaziggy · Post by **Miztaziggy** » Sun Sep 25, 2011 8:35 pm

It does take quite a while to do it.

You probably already know the correct method, but if not, then I undo both of the nipples on the calipers and fill reservoir with fluid, it will slowly drain down the lines and leak slowly from the nipple things. Close the both up and then fill the reservoir with fluid again and begin with one of the calipers.

Squeeze brake lever fully in, undo the nipple thing and fluid and air will squirt out. Dont release the brake lever, and tighten nipple back up. Now release brake and pump it to see if there is any feel there yet.

Basically keep repeating this one side, then the next. It took me about 10 repetitions per caliper to get it right.

oldbikeman · Post by **oldbikeman** » Mon Sep 26, 2011 1:47 pm

What's it like with the conversion? Did you sort the brakes?

Bigtiddle · Post by **Bigtiddle** » Mon Sep 26, 2011 8:00 pm

Yahoo!
I borrowed a Mityvac from a technician at work, pulled clean fluid through until no more bubbles and locked it all up tight. The lever felt better. I used a cable tie to strap the lever to the throttle overnight. This morning, I checked and all is back to normal. A good "feel" at the lever.

The conversion makes the bike so comfortable to ride. Wheelies easily! The handling is slightly affected as the weight is in a different position so I may play with the suspension settings but may not bother as it's fine for what I use it for.

Stormin Ben · Post by **Stormin Ben** » Mon Sep 26, 2011 11:34 pm

Bit late obviously but for future reference I always remove the calipers and pump the pistons a reasonable way out

Then when you put new lines etc on there is enough fluid in the calipers to back fill the lines and you have instant lever pressure

Ben

VTR1000.ORG