TT .91
I have a lot of experience with this wonderful engine and have posted hints many times.
Here are some tips and pros/cons regarding this engine:
Pros:
more powerful than OS, Saito, Magnum
Easy running and easy to tune
Works great on fuels from 10%-30% nitro.
Reliable!
Affordable!
Cons
Several ounces heavier than competitors
Tips:
Follow instruction for engine break in. You cannot run your engine rich enough during the break in. You engine can be flown after a tank on the ground, just richen her about 500 rpm shy of max lean rpm and then later to 300 rpm shy of max lean rpm when she is broken in.
Lube the valve train and lower crank case with some synthetic oil before first run. (I do this for all brands of 4 strokes). Low end is lubed by blowby from the piston assembly and prelubing your engine will help longevity.
The rocker arm assembly MUST be retorqued after first several runs. The bolt holding it down will loosen and may cause some damage to the head-I speak from experience. Pull the head covers at a minimum.
After breaking engine in, check all bolts on engine and valve lash.