I just recently replaced my brake line with a new one to install new handlebars on my 2005 RK. I originally bled the brakes the old fashioned way (pumping the lever and bleeding at the bleeder). I was able to get pressure and no bubbles at the both calipers. However, the lever seems to pull almost all the way closed to get braking action. So I repeated the process to the same effect. I tried tie wrapping the handle closed and letting it sit overnight. No change. So then I tried the reverse bleed method with a syringe and was able to feel a bit more pressure, but still pinches my throttle fingers when I brake. The brakes are working, but I just know its not right. Anyone have any suggestions?

 

Did the master cylinder go dry while you changed out the line? Sounds like you need to bench bleed the master cylinder as there is still a small bubble of air trapped in it. Reverse bleeding should have pushe dit out but there must be some air or it would feel the same as before changing the line.

 

Buddy with same issue. Im watchin this one

 

The master cylinder was dry for a couple of weeks. I have heard someone mention bench bleeding the master, but what is involved in that process?

 

Master cylinders by design have chambers that can trap air. Typically when replacing 1 the bench bleed process is as follows:
mount new master cylinder in bench vise
attach a hose barb fitting to the outlet
install a short section of clear vinyl tube between fitting circling back into the reservoir
fill reservoir with correct brake fluid
work plunger on master cylinder pushing air out then sucking fluid back in
do this slowly until there are no visible bubbles in the clear tube
be sure to keep end of tube in fluid as it can suck air back in on the release stroke
mount master cylinder and replace plastic barb fitting with brake line do not tightnen
slowly compress master cylinder to push out any air and before letting go final tighten barke line

 

Thanks, Scrmnvtwins. That is the best description of how to bench bleed the master cylinder I have seen. I tried searching and google and nobody really explained well "how" to do it. I will give this a try this weekend.

 

There are two Stickies in the Brakes section which may help. You're by no means the first to find bleeding bl33din' brakes a challenge!

 

I hear your frustration. I've been bleeding bike brakes for 20 yrs and always seem to have trouble getting a solid front. Perhaps cause the master is so much higher than the caliper, & is hard to push a bubble downhill doing it by yourself.

Anyway, I rebuilt both my fronts this winter & decided to install SpeedBleeders. Wow! Bleeding was a 5-min job, & I have two calipers on the front to push the bubbles through. Front brake lever is rock solid or first try. Never, ever had a brake job so easy or so quick. Can't recommend SpeedBleeders highly enough, and they're only like $7 each. I can't believe all the time & tricks I've wasted trying to get a solid lever on front bike brakes!

 

Buds issue was air in the line. Used a mity vac brake bleeder to bleed the brakes. Friend could not believe it was that easy.