Hey all I jsut got a hold of what I think to be a 1990 polaris trailboss frame. I have a dirtbike I never ride, its a 77 Yamaha DT 250 (2 stroke) Its a trail bike, and it is fast and torqey. Ive never topped it, But its a 5 speed and it only takes 2nd gear the hit 30 mph, but by then its time to shift to 3rd. But anyways, I am going to rip the motor and tranny and put it into this trailboss frame...and Im gonna make it fit and work. But my question is....Will the motor lose alot of power(speed and acceleration, mainly) because of the need to spin 2 wheels instead of 1, and the bigger frame? Does anyone have any experence with this motor? Has anyone every put a dirtbike motor in a quad before, and how did it perform compared to when it was in the dirtbike?

Thanks for any replies.

 

any time you have moving parts, you are going to lose power...and then the weight of the quad vs dirtbike will rob power and speed, and then the fricition of having two tires vs one will take away power...umm the new 450's are engines out of the dirtbikes, but just reworked abit and yeah...it is possible

 

I got a 71 DT250. Good bike. Still runs too. That motor sure has some ***** for being how old it is. Being that it is air cooled, mine at least will start shooting flames and dies after a few hours. Let it cool down and it will fire right up. Mine tops out in the mid 70's

 

Mine has never shot flames or anything like that, but how do you think it will hold up in a ATV frame?

 

There will definately have to be some custom fabrication done. But I say if you have the time and skills, go for it!

 

yeah a i read a thing that a guy put a dirt bike motor in a quad frame in dirtwheels, he made it for his kids but he said that it took away quite abit of power.

 

I'm planning on doing the same thing, I just bought a 77 suzuki 500 twin 2 STROKE street bike.WOW this thing will scream. I'm looking for a frame to put it on. It will be probly next year before it's together, I will probly ride it this summer until I find a frame. This bike is almost mint, it has 6,000 miles on it.

 

I see transmission problems in your future..............

 

Yep, tranny may be an issue. You are doubling the weight that tranny was designed to handle.