size of master cylinder piston 80 cb750c?

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size of master cylinder piston 80 cb750c?

pickandpray
I would like to replace my master cylinder.  does anyone know what the original piston size is?

I would like to improve the lever feel and need to know the original size so I can research accordingly.  it looks like 14mm to me but there's got to be someone out there who has one apart and can measure for me (or knows).

thanks in advance!
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Re: size of master cylinder piston 80 cb750c?

pickandpray
This post was updated on .
very difficult to find this as no one seems to have studied the subject or simply don't care.  

The piston size is 14mm and the same master cylinder is used for the dual caliper and even the dual piston dual caliper setups.

14mm on single piston single caliper setup like the stock 80 cb750c simply sucks in both feel and hand lever effort.

here's a chart for further reference if anyone else comes down this road looking for updated braking.

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

single piston calipers are 43mm

blogg for upgrading the calipers
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Re: size of master cylinder piston 80 cb750c?

seestheday
Thanks, I am looking into upgrading to a Nissin master cylinder and this was very helpful.  Looks like I just need a 14mm one and I'll hit the 12:1 sweet spot for my stock front brake (single disc).
1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.