Front Brake Master Cylinder Replacement Suggestions

[Tenshots1]

Hello All,

I recently noticed that my front brake lever was a little loose when riding. When I finished my ride, I found that the lever was loose because one of the two screws attaching the the brake/master cylinder assembly to the handle bars was stripped. It looks like the female/bolt side was the side that is stripped out. I could still get it to fasten fairly tight from the other bolt but am not excited to ride it in the current condition. Now, what is the easiest way to fix this issue? Do I have to go ahead and purchase a new brake/master cylinder assembly? If so, I would like to upgrade to an adjustable setup that is maybe a little more attractive. I search the forum for upgradeable options from newer models but didnt find much. What I did find was that the bore of the new model should be 5/8", which sadly I did not see listed on many aftermarket options.

So anyway,
1) can I fix this assembly easily or should I go ahead and purchase a new one?
2) What aftermarket options have you guys installed? Either new or from newer model bikes.

[bwringer]

What sort of conveyance are you working on, here? Otherwise, we'll have to assume it's a 1962 Tohatsu Runpet.

It might also help to post a photo of the situation.

Depending on the amount of metal remaining, you can probably salvage your existing MC. Hard to say without some measurements and photos.


One possibility, for example, is that you could drill and tap the threads a little deeper or all the way through and install a longer 6mm bolt.

Or perhaps it would make more sense to drill all the way through and install an even longer bolt with a washer and nut.

Or maybe the best course of action would be to install a Helicoil, if there's enough aluminum there to hold it.

There are also kits that use an epoxy to reinforce and re-create threads if things aren't totally cabbaged. However, I don't think this would be the way to go with a brake component.

[Tenshots1]

Dammit! I hate forgetting to post my bike! 1980 GS550E. I will try to get a pic or 2 tonight, although it may be hard to capture. A longer screw could be a good solution.

[habsdoc]

Edit your profile and list your bike or bikes.

[Nessism]

If you live in the US then your bike will have one disc in front and use a 14mm master.

Ebay is full of new 14mm masters for cheap. They are simple devices so no big worry with purchasing a bad one.

[Tenshots1]

Good info to kno. Thanks Nessism. I have just been amazed by how little detail many of the eBay sellers provide on their master cylinders. I am lucky to find 7/8 bars let alone bore.

[hannibal]

I asked many ebay sellers about specs of their new MCs. Few bothered to answer. The ones that did said "I don't know" to most questions including bore size. I searched high and low and ending up buying a used GS master from a guy on this forum. If I had to do it again, I would likely buy a newer used MC and rebuild that.

I'd spend time looking for a adjustable MC from a newer bike like you said. Check ebay and other bike forums. I have a short list of MCs from newer bikes that I thought would work. Kawa KLR650 is the only one I remember right now.

[Nessism]

http://www.ebay.com/itm/Suzuki-DR-200-250-DRZ-GS-RG-RMX-RMZ-SP-GN250-Brake-Master-Cylinder-BLACK-/301637532406?hash=item463aff7af6:g:Qo4AAOSwrklVWn7j&vxp=mtr

[BADJACKSON]

I'd like to replace mine too, on all of my GSs. Something along these lines...

image.jpg

I just want a smaller MC. Something that doesn't look like a Tupperware container on the handle bars.
Any suggestions????

Thanks.

[salty_monk]

Kawasaki KLR 2008+ master will work also

[tkent02]

Any master will work if it's for 7/8" bars, 14mm, 5/8", whatever.. I have used a bunch of the cheap Chinese ones on ebay, they have all worked well.

[Tenshots1]

I'd like to replace mine too, on all of my GSs. Something along these lines...

[ATTACH=CONFIG]42889[/ATTACH]

I just want a smaller MC. Something that doesn't look like a Tupperware container on the handle bars.
Any suggestions????

Thanks.

I agree. Especially if I have to get a new one, I'd love to get something smaller, modern, and adjustable. Sounds like these things are pretty universal, except that you have to try to get a similar bore.

[Grimly]

Both my GSs have XJ900 master cylinders of 5/8 bore (which is so close to 16mm, it makes no difference). Another, more modern 5/8 or 16mm with span adjustable lever is the one from a Honda Deauville (NTV650), which is my new go-to master cylinder when the XJ9 ones are beyond fixing.

For extra braking effort on the XS, I found a Kawasaki 14mm m/c from an EX500 / GPZ500S was superb, but it didn't live happily with the play in the calipers, so replaced that with the Deauville m/c.

Avoid cheapy Chinese crap on your braking system. Buy good Japanese stuff and rebuild it if necessary.

[BADJACKSON]

Avoid cheapy Chinese crap on your braking system. Buy good Japanese stuff and rebuild it if necessary.

Probably the best advice on the entire site.

[dFiddler]

Has anyone been able to find a nice matching set of Master Cylinder complete w/ levers and a clutch perch and lever?(preferably in satin black) I can find plenty of master cylinder setups but none with matching clutch setups. Only the one below and the clutch assembly looks like dog****.

http://www.ebay.com/itm/291472778887?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT