markisenberger

I just purchased a used YS F-1.20. I notice that the recommended fuel is 20/20. Coincidentally, last week at my LHS I saw a can of Powermaster 20/20 specifically for Saito and YS engines, which I had never noticed. I have always used 15% nitro in my 4 stroke engines. My question is, why does the YS have a higher nitro requirement? What engine features are different compared to other 4 strokes that cause this higher requirement? Also, I have several Saitos; the Saito manual recommends 15%. In light of the fuel I saw at my LHS, do Saito engines benefit from higher nitro content?

Thank you,

MI

btoby

some engines just do. they get even better with helli high performance 30%

Dave Shadel

YS engines are designed to run higher nitro content fuel because of the valve timing and combustion chamber volume. Saito engines will benefit slightly with higher nitro but can be run with lower nitro content fuels as they are designed for them.

Actually, your YS F120 can be run on lower nitro fuels with reasonable success, but the best performance will be obtained by using higher nitro content fuels.

NEVER RUN 4 STROKE FUEL IN A YS ENGINE! 4 stroke fuels do not contain enough oil for any YS engine.

markisenberger

Dave,

I'm confused!!!! Is it safe to assume that Powermaster fuel specifically designed for YS engines is acceptable?????

Thx,

MI

Dave Shadel

Yes, Powermaster YS 20/20 works just fine.