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New OEM front master cylinder install?

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I bought a new OEM front master cylinder  and a Galfer SS brake line.  I put everything on the bike and put some Motul 600 brake fluid in the reservoir. Pumping the brake I get nothing. No movement from the fluid at all. Am I missing something here?

 

I feel as if something has to be plugged in the master that I didn't take out. I'm not that familiar with bikes so now i'm wondering what I should look at.

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The MC's get air locked , till you get the air bubble out of the plunger it won't pump . I do a real fast pump , short stroke to try and vibrate the air out . Also often helps to force fluid from the caliper side .I've also used a syringe with a small nozzle and force fluid into the little hole at the bottom of the MC reservoir .  Keep messing with it , it'll go , sometimes being an SOB .

 

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Edited by jjktmrider

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47 minutes ago, jjktmrider said:

The MC's get air locked , till you get the air bubble out of the plunger it won't pump . I do a real fast pump , short stroke to try and vibrate the air out . Also often helps to force fluid from the caliper side .I've also used a syringe with a small nozzle and force fluid into the little hole at the bottom of the MC reservoir .  Keep messing with it , it'll go , sometimes being an SOB .

Yeah I wrestled with it some more and got the fluid to move but there is deffinetly air stuck in the system. None of my tools are really for bikes so i'm kind of stuck. I liked the caliper method but I don't have a syringe or anything. I'll have to see what I can rig before I go shopping. When using my pressure bleeder I always notice air gets stuck at the top on the  hose and the fluid just goes past it. I did the brake line aswell and let the caliper leak off some fluid so I didn't have to worry about getting it all over the annodized wheels and stuff. Its pushing some brake fluid through but its not getting the air out. I have a vacuuum bleeder aswell so i'll play with that in the afternoon tomorrow when I can run the compressor. Might have to grab a syringe.

Right now I think i'm just wasting brake fluid and its going right past the air bubbles.

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Made a little progress today but I still feel as if there is air in the system. I ended up taking the perch off, filling the res and holding it as the highest point. Then played with the master with it high up and now i'm getting some feedback and it will stop the wheel from spinning under hand power. Haven't taken it on the road yet.

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These with the hose going straight up from the MC are the worst for holding air bubbles . Others I've loosened the banjo bolt and spun the hose down so the MC is the highest point in the system and bled it that way, then barely loosen the banjo again and spin the hose back up , then a little more bleeding does the trick. To save fluid clamp a hose on the bleed fitting down on the caliper and route it into a clean container so any fluid coming out can be dumped right back in up top . With enough bleeding the air will come out , it may help to have a buddy or wife do the lever pumping and keeping the res topped off while you do the loosen-tighten thing . I have a check valve setup to replace the bleed fitting for the hose to clamp on to so one person can do it easier . Takes time but it is really nice having no sponge feeling when using the brakes.

 

 

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Edited by jjktmrider

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I use a large syringe from a feed supply store to force fluid in from the caliper. This is the best way I have found to force the air out of the system. 

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What is a feed supply store?

 

Yeah the place I bought the bike from apparently had a hack job put the bike together from the crate. Sloppy job on nearly everything, minor misalignment that just look like the tech didn't care. The brakes always seemed to feel pretty spongy. But I wasn't sure if that was the rubber lines expanding or something.

 

Luckily I have a bunch of Motul fluids. I run a lot of there stuff in my M3 which I wrecked so I have loads of fluids to waste. It was a pain in the ass but the best luck I had was taking the perch off and holding it sideways and pumping it a little. Only problem is you can't really tell where to fluid is in the res. And the entrance to the system is in the dark. Real pain in the ass I wish they had a round res so I could just pressure bleed it.

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13 hours ago, SKIPPY PB said:

What is a feed supply store?

A place that sells supplies for horses and other animals. Veterinary supply stores may also have them. Use a piece of tubing around the bleeder bolt on the caliper to force brake fluid into the system from the bottom. Make sure the reservoir on the master cylinder is empty when you start and keep an eye on the level. Clean any spilled brake fluid off immediately or it will ruin the paint.

Syringe.JPG

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