the joy of a minibike is that your first question is pointless... if you have a 427 V8 lying around, and know how to engineer it...
some people might say its silly but im going to have a go with an os fs 26, or a whole 4.2cc
just gotta convert it to petrol...
basically, the limitations are you, your abilities and your imagination...
taco? sounds sus to me... maybe im just opinionated, but that name just conjures up images of dodgy dodgy. never heard of it before, so dont listen to me!
dont ride minibikes on public property! ie, look out for the po-po!