Re: what is the best motor available?
This is the toughest question to answer because it depends on a lot of things.
A Morini motor is considered by many to be the best, but will not simply bolt on. If you are not a welder, it's not the best motor for you.
The latest SpookyTooth death race was won by an electric bike (Yes, it beat two Morinis), so you cannot rule them out if you can afford it.
Tanakas are powerful if you want a rear rack mounted motor.
If you just want more speed, a china girl motor with an expansion chamber exhaust and shift/jackshaft kit may work best.
It just depends. Keep reading the forums to see what works for you.
“You're only young once, but you can be immature as long as you like" -Unknown