RE: Saito shuts off
I've had a saito shutdown on me before while running at high rpm, over 10k, back when I was a newbie. I had the valves too tight. Engine just up and died. After several trial and error fix attempts, I adjusted the valves again to the low end of their range and ran the engine at a lower rpm. No more problems. You might give that a try. I tune and prop all my saitos for around 8500rpm to 9500rpm. Have a couple of 120s with well over 200 hours run time with only tear down and carbon cleaning done. Still all original parts. Just my opinion, but running them over 10krpm regularly is kind of hard on the engines for long term life.
Edwin