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rebuilt calipers - now master cylinder problem
Like it says - This bike sat about 8 years and I towed her home for a rebuild. It's running now and I rebuilt the rear caliper when I had the new E3's put on last month. It was slowing down using the downshift/squeeze brakes/drag feet/pray method. I then rebuilt the rear caliper and I deleted the drag feet from the braking procedure. Now since I have a 250 mile cruise planned for tomorrow at 8am - I planned way ahead and rebuilt both front calipers tonight. All went well - until the bleeding procedure.

Both front calipers were frozen so I had a rock hard front lever and foot brake. The lever would only move 1/4" when I put the death grip to it. Well, after the caliper rebuilds, the lever falls all the way down to the handlebar. After a half a small bottle of brake fuild being bled (wife squeezing-me bleeding) through the front master cylinder I have maybe 1" of room before the lever would hit the handlebar. I could see the pucks move the new brake pads up against the rotor so I know it is moving fluid. But what's up with this?
The rear foot brake system bled and built up presure quickly, like normal. The foot brakes works the rear/right front great. I can now remove much of the downshifting and prayer when I took her out for a spin just now.

Ideas please - Also, when I was scraping the muck out of the bottom of the front master cylinder - I knocked over a small metal piece of metal. I think I put it back where it is supossed to go? I can't find a pic of how it's supossed to go?

Thanks a lot. If I live through the cruise tomorrow - I will fix it pronto - If I could figure it out...
#1 03-18-2011, 06:43 PM,
Providing you have the little metal piece in correctly, there was a picture of that on the forum a while ago, if it refuses to bleed correctly, try loosening the banjo bolt slightly and as you pull the lever slowly tighten the bolt, this should get rid of any trapped air in the master cylinder.
The only stupid questions are the one's that are not asked.

#2 03-18-2011, 07:14 PM,
Newbie question:...What's a "banjo bolt"?
#3 03-19-2011, 03:19 AM,
The bolt that holds the brake line onto the master cylinder.

If it is proving difficult to get all the air out, by loosening it slightly (lots of rags underneath this stuff eats paint) pulling the lever then tightening the bolt before letting the lever back out it can allow the air to escape.
The only stupid questions are the one's that are not asked.

#4 03-19-2011, 06:04 AM,
The banjo is the eye on the end of the brake hose at the master cylinder, this is where a bubble of air likes to get trapped right up against the master cylinder since it is the highest point in the system. This bubble can be a bear to bleed out and often you may need to slightly loosen the bolt through it (the banjo bolt) to get that bubble out.
Also turning the handlebars all the way to the left (for the front brake) whilst leaning the bike hard to the left and leaving it with the lever tied pressed against the bars overnight will also get this bubble out. Often you can do the same thing in reverse for the clutch, or a heavy block on the peddle for the master.

Most common quote from a cager after killing a motorcyclist.

"I never saw him" instead of "I never looked for him".
#5 03-19-2011, 06:09 AM,

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