What size MC for dual discs?

[Big Rich]

I swapped the forks and got a set of calipers & rotors from a GS650 (not sure of the year/model). The original master cylinder is on another bike all together so I was looking for an aftermarket replacement. Any ideas what size piston diameter I'll need in the new master cylinder?

Thanks in advance fellas.

[Big Rich]

Did I ask this question in the wrong area of the forum or something?

[SVSooke]

I figured someone else would answer so.......The answer is 5/8 or 16mm.The one on my 85 750 is 5/8 and I just seen a 16mm for dual discs on MikesXS.At least that's where I think it was.

[waterman]

Did I ask this question in the wrong area of the forum or something?

No this is the correct forum, I think it stopped raining and we all went for ride yesterday.

As SV stated, look for a 5/8 inch or 16mm master cylinder. I am looking for a replacement myself, supposedly any dual disk master cylinder will work. Pay attention to mirror mounts and angle orientation of reservoir, when the MC is on handlebars, the reservoir should be level with ground. Many MC are angled to fit the angled handlebars of sportbikes.

[Big Rich]

Thanks guys!

I plan on using a remote reservoir and have bar end mirrors, so that shouldn't be a problem.

[Billy Ricks]

Thanks guys!

I plan on using a remote reservoir and have bar end mirrors, so that shouldn't be a problem.

GSX-R stuff will work for you then. I'm using one on my bike.