Does a 91 kx250 and 91 kdx250 have the same Top end kit?

I was looking for a Top end kit for my 91 kx250, in doing so i noticed that the price difference between a kdx 250 and my 91 kx is $50. but they share the same part numbers from Wiseco and Kawi.

Would i be safe to order the kdx kit?

I haven't specifically looked at the part numbers for the '91 KX250, but I can tell you that the KDX250 Wiseco piston is the same as the '90 KX250. So if the '90 and '91 KX250 piston are the same (probably are) then the p[iston will work. However, if you are talking about the whole kit, the head gasket for the KDX is thicker than the one for the KX, and will lower your compression. I always ran a KX250 head gasket on my KDX250 to raise the compression.

OK I think I'm safe with the KDX piston then. I think the gasket is sold separately anyway. Is it necessary to also buy the pin bearing? I see it doesn't come with the standard Wiseco kit.

The pin bearing doesn't come with the Wiseco piston kit, so you will need to get one. I also think that piston is the one you want. I have a 91 KX250 and have used that piston and I think it says it;s for the KDX also.


Thanks for all your help guys,

The Wiseco piston is for 1990 - 1991 KX250 and 1991 - 1994 KDX250.

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