Best Grass Gear ratio- need help

[Rorycall]

Hi everyone, I am new to this forum and I am really stuck on my off-road kart. I bought it a few months ago as a project and I’m only a teen so I’m just beginning with engines, a mechanic friend helped me get it running , i don’t know what brand the frame is but it has a gx 200 clone engine and a centrifugal clutch, it won’t get any power or speed on grass and I think I know why, 1: one of the front wheels is out of line with the other one,
2: the engine is not modded in any shape or form (which I plan to do)
3: I am running a 12 tooth to 33 tooth ratio, which is not meant to be good for a 100kg+ Off-road kart I believe.
Would anyone know what I should do and what rear sprocket i should use?
Also my wheels are 13 inch I believe.
Any help at all would be greatly appreciated,
Thanks

 

[Nosandwich]

This is where you introduce yourself not ask redundant questions.

 

[landuse]

Welcome to the forum! Have a look in your other thread for answers