http://www.vmaxforum.net/showthread.php?t=2231&page=7
FJR masters are a popular swap.
Vmax masters have a 5/8" bore for both clutch and brake.
Anything close will work.
The smaller the bore, the easier the lever will be to squeeze but it moves less fluid so it will take more lever movement to have the same effect.
14mm is a popular size to use. Some of the radial calipers can also be used. I'm not up to speed on what size radial master is a good swap though. As noted, the zx-14 has been used with success. I found that the kawasaki concours has a 14mm clutch master.
Gen 2 busa's have a 14mm front brake master but the reservoir is angled a good bit.
unk:
