Float valve seat size

[RMT1983]

Should be 1.0 on the 600s

I would strongly recommend against cheap replacements and only use quality seats & valves.

But.... why are you changing them?

What's yours symptoms?

Thank you...
My bike was severely flooding and overflowing, seals had perished from standing. I will admit I was cheap and ordered a cheap rebuild kit and the ones they sent out was a 2.0, prompting my OP. 
Bikes sorted now runs brilliant.

All you needed were new New O-rings which are cheaper and better than any spurious float valves. the Mikuni originals are a very high quality item

Erm.... no. Not always.