YAMAHA YZ490 go-kart?

[parrish5o]

Am I crazy for pondering this? My cousin has an early 90s maybe late 80s 490 with a serously broke frame. I can get it for next to nothing and don't know of anything else to do with it. Can't let that much power go to waste. As far as I know the only drawback is the fact that it's not correctly balanced for a large heavy frame, sort of like using an atv to put it in, right? I have alot of researct to do still, but I know it can be done. Just will it work, be safe, shake itlelf apart, or just be one hell of a ride. Another motor option like is a street bike ie. Ninja 900. I'm planning a frame based on a Honda Pilot(full cage/5pt harness). I've seen similar setups at the dragstrip run low 7s!Whats your opinion?

[crwth2]

once took an old two seater gocart frame and weled a four wheeler front and rear end to then ran it with a honda 400 street bike engine and it did just fine