FINALLY got an XS650!

The good news is there's nothing mysterious about hydraulic brakes, the bad news is you might need to spend some money. Don't know about you but for me a front brake that works is a very high priority. Pretty much like refurbishing anything, get the brake off the bike, dismantle the brake line, master cylinder and caliper. Often the piston is stuck inside the caliper - penetrating oil and wait and if that don't work move on to further measures. If it's the original rubber brake line, I'd recommend upgrade to a braided steel line, one piece with no union half-way along. Clean the master cylinder, there are kits to replace the piston and spring but it's worth thinking about investing in a new m/c with a smaller piston - I did this and well worth it for a much better 'feel' at the brake.

Post photos and questions as you go . . .
Made a ton of progress in the XS. Way too much to list but I could use a hand on my front brake. It's never worked, the master cyl is bone dry and when I put fluid in it it doesn't go anywhere. I'm honestly used to drums, all my other bikes are drum but I did look up the bleed process and some related threads but am not finding a solid walk through of what to do.

hi stillgo,
later than ~ '74 XS650 front brake m/cs are sized to work the TWO front disks that Euro and Far East XS650s had.
Which is why your North American model XS650's single disk will feel like wood after it's bled.
Look in the "search" box for "front m/c seal size" & "front brake bleeding methods"
I use a lever action oil can to pump brake fluid in through the brake caliper bleed nipple hole so the system fills from the bottom up.
I'm having the worst time ever with my brakes. My theory was hey, I'll just swap the shoes and go through the rear setup so I can at least take the bike around the block here and there until I figure out the front. Well, I got shoes from Mikes, took everything apart and long story short followed all the advice on here. Brakes either didn't stop me at all or would be tight and kinda slow me down. Read more here, went through everything again, a bit better and I sure shit finally took those trips down the block. I could live with the rears as they break in if I had a front. Again I read alot of the forum and info on others struggles. As far as I can tell I need a new MC. I tried every bleed procedure known to man, oil can pump from caliper, all of it. I don't think my MC is doing a damn thing. I took the lines off, took the caliper apart and I really don't know what I'm doing as all my other bikes are drum. After a nightmare trying to get the caliper back together right, lines back on (with fluid in em) I was hoping it was the time I get some action...nothing. I haven't taken the MC apart. I can fill it and with the banjo bolt off it won't even come out when pulling lever. Yes I cleared the bigger and smaller hole in MC. I also read of people getting MC from Mikes and them not working. I'll probably sell the bike to my friend who's lurking like a wolf in a fit of rage if I can't figure out how to make the damn thing stop.
Try this Chinese m/c they have worked for me a couple times now.

Also a vacuum bleeder is one of the handiest tools ever!


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