Ok so I finally decided to run 30%. How hard would it be to change over from 20 to 30 in a motor that has about 3/4 gallon of 20 on it? I know I will have to tune it. I just didn't know if it would run worth a crap or just keep runnin 20 on it till it dies lol
Help please

also I was thinking maybe mix 20 and 30 half/half so that it wouldn't be such a huge tuning diffrence. Also what will I have to concentrate on first? hs/ls?

On my os cv-r I ran a gallon of 20% then switched over to 30%. Just richen up both of the needles and retune. Been running 30% ever since.

cool ...the motor I have is a os cvrx

Let me know if you need a piston/sleeve if that motor ever needs it. I have just under two gallons on mine and don't use it anymore.

ok

if it starts being difficult to tune u may need to raise the deck height but it should be fine

just put the 30% in the tank and run it, tune if need be. Don't start twisting needles until you try it first.

DON'T do it this way. You will end up having to re-tune twice. Better to just run off the 20% you have, so it doesn't get wasted, and switch to the 30%.

wow that is way over my head lol. What is the deck height?

the distance b/w the top of the piston at TDC and the head button. When the motors are run lean or sometimes if u raise nitro, or if the deck height is too low, you will get this pitting on the head button and top of the piston.

ok man this is gettin confusing lol

basically just put an extra shim if needed when you switch..........like if your having problems with the engine, like its blowing plugs, or running very weird, like to lean or wont stay at a conistant tune

ohh ok like a shim on the plug huh. I never realized all this could happen just from changing fuels lol

no a shim under the engine head

ohh ok. I think I'm in the area now lol