I searched "ef2000is valve" looking for info about valve clearance. One thread listed the intake @ 0.15mm and the exhaust @ 0.20mm. When I check my manual I am given a spec of: 0.07-0.12mm.
When checking the spec on my engine with a feeler gauge I am at 0.08mm.
My manual is the Yamaha service manual LIT-19616-01-53.
The closest Google search sent me to this forum.
The poster that uses the larger spec is quoted in several threads, and seems to be to be credible.
This is my first valve adjustment on my engine. I wanted to double check my spec, due to what I read to be multiple versions--US vs. China--that might be different. My generator was purchased in October of 2011.