Originally Posted by Oso787

I have always wondered, what are the main differences in the same model engine on/offroad versions. As I understand it, the companies use a lot of the same components but change, carbs, timing on crankshaft/sleeve height. What are the most obvious differences between the two models? Is it possible to modify an off road engine so that it performs as fast as its onroad counterpart? Thanks for your time and patience.