1992 KDX 200 with KX250 motor?

[OnWheels]

Hi everybody, new to the board. Have had a KDX for a while now, but it has never had a motor in it Picked up the bike for $300 rolling, just recently I spotted a 1990 kx250 motor on eBay, and figured they were a match made in heaven. Got the motor for another $300 and now am planning on rebuilding the bike. Now can anyone tell me the main differences between a KX250 and KDX 200/220? Am I going to run into any problems trying to fit the 250 in this frame?

Thanks

[SS109]

Yes, you are going to have fitment problems to solve. The KDX engine was based off the KX125 engine and the chassis is built with that in mind. Also, I don't know how well the chassis will deal with the extra weight and power of the 250. I would really look for a KDX engine myself.

[OnWheels]

Hmm that's not what I wanted to hear. I would have thought the 200 would have been a similar frame to the kx250. Kdx motors are hard to find down here. Would there really be much weight difference? I thought the kdx was just a detuned kx

[SS109]

Would there really be much weight difference? I thought the kdx was just a detuned kx

I can't honestly say what the weight difference is. Maybe a member has one out they can weigh to let you know.

As for a detuned KX, well, not really. It is literally a KX125 that has been retuned for low end and given a longer stroke/larger bore combo. The only KDX based on the KX250 engine is the '91-'94 KDX250 which is a completely different animal than the KDX200/220 bikes.

[Julien D]

SS is right. You'll likely be looking at enlarging the engine cradle. Not fun....