Need some help.

[bobmcmillen11]

Just traded for an '84 KDX (red). It has a non-running engine, but the deal included a spare (running) engine. Did the engine stop and am ready to try it as soon as I find the right throttle cable. These engines should be the same, I think. Serial numbers are DX200AE000706 and DX200AE003899. The countershafts are different - sprockets not interchangeable. What's up with that? So I looked into the non running engine and thew piston is hitting the head. The only dimensions I can find are 66mm x 58mm. To date, I don't know whether cyl is too short, stroke too long, wrong piston, or maybe I need 3 or 4 base gaskets. Any ideas?

[Julien D]

Interesting. Maybe some pics of both engines will help? For the piston hitting the head, I would guess the wrong piston or connecting rod was installed. If the Counter shafts are different, they are likely to be different years.

[bobmcmillen11]

Well duh! Turns out the bike had a 240 bike bore kit installed, but a 200 cc headgasket. I'm sure it never ran that way, although the gasket is slightly mangled. On a happier note, it also had a shifting problem which was cured with a simple hardware store spring. I'll order the OEM spring soon.

[KDXGarage]

Lower numbered engine is 1983. Higher numbered engine is 1984.

Good luck!