KDX250 info request

[dblakey]

Hey,

Just found this site and have been searching for KDX250 info for the past hour.
I just traded for a relatively complete 93 KDX250. It is all there, but has minor engine problems.
My main question is, I have one case half with a crack in it around the drain hole. Need to know what cases will fit this? I have a line on a 91 KX250 set of cases, and need to know if it will work? What years if any KX case will work since there seems to be a lack of used parts avalible for the KDX.
Also, it appears the cylinder has been resleeved at some point. Would like to know what the stock bore is for this bike? I have not had a chance to get a manual or do much searching. Basically, I am just trying to figure out if this engine is worth saving or not.
Any help would be appreciated.

Thanks,

 

[43Duc748]

I think I read that the 88 KX250 is the same motor. Do a search on this forum for kdx250 and you should get several pages of threads that may have some help for you.

As for the bore, I'm kind of an idiot when it comes to technical aspects, but my manual shows the cylinder diamter to be 67.405 to 67.420 mm. Is cylinder diameter same as bore? If not, let me know... I have a manual for the 91 KDX250 right in front of me and they 93 and 91 are identical.

 

[dblakey]

Thanks,
From your numbers, it appears the bore alittle oversized. Mine measures (as best I can tell) at 67.80mm. Does anyone know if this a standard piston size? Can oversized pistons be purchased?

Now for the crankcases.
Mine is a 93 KDX. I have a line on a set of 91 KX cases. From the numbers I can find, the 91 KX and 91 KDX share the same cases as far as part numbers go. However, the 93 KDX has a different number than the them.

So now I am to the point of finding out if there were any significant changes from the 91 KDX to the 93 KDX.

Was there any change in the model years of the KDX as far as the crankcase halves go?

Thanks

 

[glad2ride]

the crankcase part numbers are the same for 1991 all the way through to 1994 for th KDX--250, kx is different numbers

 

[DaveRS575]

you can look on www.BikeBandit.com for OEM part numbers. They can be a good resource for exploded views and #'s....Their OEM parts are pricey if you go for new ones, but where aren't they expensive?

I have a 1991 KDX250 as well as my 94-200 also siting in my garage if you have any specific questions that I can help with visually.