I`ve decided to dump the hydraulic drive, too much cooling system and no room to have it.
Shall now take the power from both sides of the crank. This may save me from welding the crank when running on Nitro. Had almost decided on splines, but conical ends are easier for me to make, and will allow variator drive. I need to make a mod on the swingarm to allow having a shaft through it, between the swing bolt the back wheel.