I want to take my 400 motor out of my 400EX and replace it with either a 250R (86) or a CR500 motor. Which is better? More reliable? Can the 400EX frame handle the CR500 motor? What is the best year for the CR500 motor?

I am done with the 400 motor. After riding my (86) 250R ATC and a friends (03)Basnhee, I want a 2 Stroke again, but in my 400EX frame with my awesome suspension I added.

Will this be a pretty easy conversion?

Thanks for all the info....

 

'85 is the strongest CR500 motor.
Good luck fitting either unit into that chassis, as I'm sure it will take quite a bit of fabrication.

The CR500 motor has no counter-balancer and is not designed for low vibration. I have a buddy who's got a CR500 powered 250R chassis.... The thing absolutely RIPS! Whips up on everybody (When it runs) It vibrates quite badly, breaks motor mount bolts very frequently (Seems like every ride) and is somewhat unreliable. BUT IT'S REALLY FAST! (Banshee's are traction)

 

I just sold our 89 259R W/built 91cr500 motor in it
I a hated that motor, its hard to kick it viberates to h#ll and i still have a hole in the bottem of a pair of K-SWIFT shoe's
But it was fastttttttttttttttttttttttt
my suggestion to you if you want to go fast and do a trick motor swap--Banshee or street bike motor or better yet build a SPARKS 465 do every thing and keep your bike looking as stock as posible (stock uncut fender's ect.)[img]i/expressions/face-icon-small-smile.gif[/img] SLEEPERRRRRRRRRRRRR[img]i/expressions/face-icon-small-smile.gif[/img]

 

like the previous guy said, the cr500's are hard to kick because they are kick back, not kick forward. If i were you id built a 250r motor with a big bore kit. I have a gas 370 that lays the smack down on methanol 465ex's. The 500 would rattle you stupid...you'd get off that bike drooling and wondering why you couldnt feel your hands. You could put lead shot in your steering stem and mount your motor in rubber and it still wouldnt help (we used to TT a 500 in a 250r frame so i know) go with a honda motor!