I pulled everything off a 1997 1200 and threw it back into a rigid frame. I'm having issues bleeding the front brakes now though.

I hooked the brake line back up to the master cylinder, bolted the caliper back on, attached the brake line to the caliper and tried to manually bleed the brakes. Nothing happened.

Undid the banjo bolt from the caliper, pulled the brake lever and fluid is definitely traveling from the m/c to the end of the brake line.

Picked up a mityvac and it's been pulling a ton of air and a little fluid but it never gets to the point that it's only pulling fluid. Went through 2 m/c full of Dot 5 and I'm still getting mostly air.

Filled the caliper with Dot 5 through the banjo bolt hole and the mity vac sucked that fluid out through the bleeder but then went right back to mostly air.

Any ideas on why I'm getting so much air but it never starts sucking out just fluid?

 

should mention I'm using stock m/c, stock brake line, and stock caliper. had to get a new bleeder screw from O'Reilly's because the dude who owned the bike before me had stripped the hex to the point that it was almost perfectly round.

 

Did you bench bleed the master before you installed it?

 

No I didn't, but if the m/c is pushing fluid into the brake line is that really the issue? Have to be honest, brakes are not my thing at all, just did a quick search and can't find good info on bench bleeding (apparently computers aren't my thing either).

 

this sounds dumb but it happened to me. When you try to bleed the brake is the cap on the M/C? I was trying to do it with it off once and it was sucking air like mad.

 

When I swapped my bars last fall, I had the same problem, and my brake lever was very mushy. I found a trick online that work very well for me.

Hook everything back up, make sure the m/c is filled to the proper level and the cap is on. Pull in the brake lever and use something to tie it off like that. Leave that way over night. Apparently this allows the trapped air bubbles to rise to the top.

Brakes aren't my thing either, but this did work. The next morning I removed the para-cord I used to hold the brake lever in and the brake was much better.

Good luck.

 

I copied this from somewhere but it works well.

Bleeding brakes
Items needed: (a) 1 empty, dried out clear water bottle (1 pint / half liter), with cap.
(b) about 2 feet of vacuum hose, just big enough to fit over the bleeder on the caliper. This needs to be a tight fit, so that you have to push it over the taper/bubble of the bleeder.

Drill a hole in the water bottle cap just big enough to fit the vacuum hose though. Push hose into bottle so that end of hose just touches bottom. Pour enough new brake fluid into bottle to cover end of hose by about 1/2 inch. Put other end of hose on bleeder screw and open bleeder. Now pump your brake pedal, watching the bottle. You should see air coming out of the submerged hose. This will then suck fluid back in.
I use this method ALL the time working on cars.
Good luck. Let me know if I haven't explained it very well, and I'll post a pic of my setup.

p.s. If you don't see any air, you might take the brake hose off at the master cyl and hold a finger over the outlet of the m/cyl while pressing/pumping brake pedal. This will help expel air under pressure, but your finger will keep it from sucking air back into the cyl.
Also you can take a suringe and a piece of hose and put hose over bleeder screw and force fluid up
towards master cylinder

 

Yup, worked for me on 2 different occasions.

 

Tried plugging the opening in the mc with my thumb and pumping the lever, took the caliper off and held it above the mc, kept using the mityvac, tried manual bleeding and no luck.

I'm still getting some fluid but mostly air. With the mityvac I can literally keep trying to bleed for 2+ hours non stop and no luck.

Just zip tied the lever to the throttle grip and will check it tomorrow.

I have the inspection with State Patrol to title my build on Monday. Hoping I can figure it out before then. This is all that's holding me up.

 

Did you ever bench bleed the master cylinder like I suggested this morning? If not, you may never get the system to bleed...Work from the top of the system to the bottom. Bench bleed the master, then attach the line and bleed it BEFORE you attach it to the master (use your thumb and fore finger to seal it when you squeeze. One you have good pressure coming from the line, attach it to the caliper and finish bleeding the system. If this doesn't work, something is defective...