KDXRIDER.NET

Hi everyone, I'm new here! I picked up a 1991 KDX 200 the other day that needs some work and I'm starting to tear into it. The main problems are a break in the case behind the kick starter gear, and low compression. I need to know what year cases will work with the internals of my engine, and why would the compression be around 100-120 WOT kicks. The engine does not run (was told it did), but will smoke when kicking. I obviously attribute this to such a low compression number. The problem is, I pulled the cylinder a little earlier today and noticed the piston looks basically brand new... The rings aren't broken, no scratches in the cylinder and the head even looked perfect... I assume the crank is good as well as the rod as there is no up and down play, very little side to side. I did notice the piston had a lot of side to side play on the rod, not sure if this is normal?

Any suggestions on what can be causing the low compression? It still felt like it had compression when kicking it the gauge just said it was low... Compression gauge took about 7 kicks to get to 120. Reeds looked good.

Thanks in advance!!

Might be worth checking your gauge. The compression might be ok but the gauge may be out of wack. Also you might want to check the bore size compared to the piston size. The cylinder might have been bored at some point and then a stock piston put back in.

Not starting is either a carb problem or a spark problem usually. The compression readings are pretty low but I would think it should still at least start.

As for the cases you can check here, http://www.oem-cycle.com/KAWASAKIKDX200BIKEID.shtml but it would probably still be worth looking up the part numbers on an OEM parts site.

Awesome website, thanks for that. I thought it should run also, I had a 85 yz250 that would run with drift started with 90 psi compression... I guess tomorrow i'll check bore size vs piston size and see what's going on there... I'm not sure the carburetor is even correct for the bike, i did take it apart and clean it...

EDITED; 1990 - 1994 KDX200 on the cases. www.kawasaki.com, Owner Info, Parts Diagrams, then use the menu sytem to selecet your model, then parts diagrams, then crankcase, and click on the part number, then the black question mark in the yellow circle to see which other models had the same part number.

It should run with those compression numbers. Spark, Gas, Air one or more is the culprit. Check spark, put in a new plug, fresh gas, clean filter, clean the carb. You said it smokes while kicking but won't run? Never seen a KDX do that. Is it that it won't run at all, or it won't idle?

after you kick it over a few times if you pull the plug is it wet?