Need some master cylinder knowledge

[lemonhead]

Does anyone know if a '79 xs400f front master cylinder reservoir is the same as on a twin disc xs750/850/1100 m/c? I am collecting parts to do a dual front disc with the factory look, but a large majority of the reservoirs on ebay m/c's are either very weather checked or require a few extra dollars. So, if I can just swap my good reservoir from my 400 to a twin disc m/c and save some cash, I'd be no less than thrilled.

Any other general twin disc conversion magic anyone wants to share would be welcome as well.

 

[Sesty]

its the same as the 77-79 xs400 as per boats.net...

I would guess you want a larger MC for a dual set up...

 

[motoTrooper]

I believe the old XS400 one was a 5/8" (it's cast into the master somewhere on it.) Use this chart to find your optimum master cylinder size.

http://www.vintagebrake.com/mastercylinder.htm

Oddly enough when I fit a twin brake setup on mine the recommended size was 5/8" meaning the single caliper alone would have been 'overpowered' by the stock master cylinder reducing effective feel at the lever. My XS400 master was worn and so I utilized an FZR600 5/8" master cylinder. It depends on what bars you are using if it will fit or not. Some masters fit clip ons better than bars etc. Anyway something modern is the way I'd go. Hope it helps.

 

[lemonhead]

Ah, I forgot to look at the boats.

Yep, the 750/850/1100's are factory twin disc, so an 1100 m/c should do the job.

That m/c chart is interesting...I'll have to measure and see where the numbers land.