I have an 88' blaster that is all stock and original but the engine is getting kinda messed up.  I heard you can put bike engines in the blaster like a yz 250 engine and that it would work. I am just wondering if that would work or would it not even be worth it.

Thanks, Blake

Nah, don't bother.  Even if you could shoehorn a YZ250 engine in there, you'd still be stuck with an '88 Blaster chassis.  ATV technology has progressed a lot since then.  By the time you spent all that time and money modifying a Blaster, you could just buy a new and better ATV.