master cylinder

[bikemight]

Hello. I'm new to the sight and recently bought a 1980 xs1100 mns. I'm looking for a new master cylinder. Does anyone no of a after market master cylinder that would work for my bike? I was interested in one that was on the mikes xs site but when i asked them if it would work for my bike they said they didn't have the schematics on the xs1100. So it may or may not work. Has anyone here used a master cylinder from the mikes xs site or know of another one that would work. Any help would be greatly appreciated thanks.

['OlGuiltyBoy]

I think if you look on the bottom of the cylinder there is a size/diameter. You just have to get one either that size or a tad bit smaller ... Don't go too small though because if you tap the brakes you be doing a stoppie and dump your bike

['OlGuiltyBoy]

http://www.xs11.com/forum/showthread.php?t=34389


Check out this thread too ... I basically had the same question

[bikemight]

Thanks. I think I'm going to go with the 16mm bore dual disk master cylinder that is on mikes xs site. It's all black and will look good on my mns. I also just installed new ss lines and brake shoes. Hopefully I can get it on the road before the weather in Seattle goes south.

['OlGuiltyBoy]

Thanks. I think I'm going to go with the 16mm bore dual disk master cylinder that is on mikes xs site. It's all black and will look good on my mns. I also just installed new ss lines and brake shoes. Hopefully I can get it on the road before the weather in Seattle goes south.

I'm not sure what stock size is, if you find out let me know ... lol. I put all that on hold until I finish up the exhaust. Had too much going on at once. but like I said make sure 16 isn't too small. Those SS brake lines are going to add some power too because they don't expand like the old rubber hoses...

[bikemight]

Pretty sure the 16mm is stock for the mns but I'm not sure about other models.

[natemoen]

Thanks. I think I'm going to go with the 16mm bore dual disk master cylinder that is on mikes xs site. It's all black and will look good on my mns. I also just installed new ss lines and brake shoes. Hopefully I can get it on the road before the weather in Seattle goes south.

you have the right one there. have you tried cleaning your current master cylinder?

[crazy steve]

Pretty sure the 16mm is stock for the mns but I'm not sure about other models.

All of the XS11s (except for the '81 MNS/XJ with their 'split' braking system) used a 11/16" bore master (about 17.5 mm). The 16mm will work, but will give a bit more lever travel...

[mack]

Brakes

I used the one from Mikes on my 79 SF, works great with SS lines. That braking system steve refers to gave me the creeps on my 81 LH. I've completely removed it and and went with the smaller rea rMC from a 79 (thanx Andreas) and will use the Mikes 16 mm front MC.

[XS1100_OEM4ME]

Welcome

Hello. I'm new to the sight and recently bought a 1980 xs1100 mns. I'm looking for a new master cylinder. Does anyone no of a after market master cylinder that would work for my bike? I was interested in one that was on the mikes xs site but when i asked them if it would work for my bike they said they didn't have the schematics on the xs1100. So it may or may not work. Has anyone here used a master cylinder from the mikes xs site or know of another one that would work. Any help would be greatly appreciated thanks.

Welcome to the site, sounds like you may have already ordered the new M/C for your bike. If so, it should work fine, the smaller bore will increase the PSI but reduce the amount of fluid per leaver movement. All that means is your leaver may move more but will act stronger when engauged, especialy with the SS lines. What was wrong with the OEM M/S? Most can be cleaned inside with scotch bright and re assembeled with new fluid to work fine

[petejw]

fwiw my bike 81R and the 80 standard are fitted
with 5/8 in bores, so theyll also work without
any problems.

[bikemight]

I bought the bike and the p/o had an existing problem of the brakes locking and not relieving pressure. He had also broke off the mirror and broke of a tap in the mirror mount. I bought a rebuild kit and cleaned it out meticulously. It was sparkling but after putting in the rebuild kit I still had the same trouble. I have already taken the mc off twice now with no new results. I will just feel safer knowing the master is new and can mount a new mirror. I want to get it on the road before the season changes. I appreciate the help and I'm sure this won't be my last question. I did end up ordering the 16mm mc from mikesxs and should have it on this weekend. Barring any rain on sunday should get it on the road.

[Rasputin]

Sounds like the spooge hole in the existing M/C has not been cleaned out and is plugged. The Mirror mount is just one enormous PITA too.

[petejw]

I bought the bike and the p/o had an existing problem of the brakes locking and not relieving pressure.

thats a common problem with these m/c,
if u remove the top and look inside there are 2
holes the smallest hole (spooge hole) blocks up and
usually needs a poke with some wire to clear it, that hole
relieves the pressure and returns the fluid back to the
reservior. You could try this til u get ur new 1.

[natemoen]

Yup, spooge hole. It is a very small hole specifically for releasing the pressure.