KDXRIDER.NET

So I installed the piston backwards in my 86 KDX200 upon rebuild. Yea not proud of that. Anyways tore it down got some gaskets, a piston, and sent the cylinder to be repaired.

It was rather a pain to tune before and I excused this as being because of the new somewhat universal Mikuni VM34 I got off bike bandit.

I put VForce reeds in it and all new DG exhaust. It ran and I went through the break in and was riding it like normal. The day the rings finally hit the exhaust port and ruined everything it was running really well actually. Amazingly the spark plug after a few hours of riding that day was the most perfect caramel color I'd ever seen. Haha

Anyways, I'm wondering when I put it all together how it might need to be tuned.

If my carb is jetted and tuned to make it run with the piston backwards how might I need to alter it with the correctly installed piston? Would it be too lean or too rich? I know it might be a slim chance of anyone really knowing how to answer this question but just figured I'd throw it out there. I'm just scared to start it up and lean it out before I seat the rings again or something.

good question since a backward piston limits the intake flow. you'll just have to see how it runs and go from there.

I have my notepad at home with all the settings for it now and I noted all the settings the new carb originally came with. I might put the original jets back in the new carb and see where it is from there. I think I was fighting the lean bog in the pilot circuit when it was running, which I got mostly worked out, so with the better flow in the piston I might need to richen it back up. I dunno. Any help, ideas, or suggestions from you guys is greatly appreciated!

Update:

Figured I'd update in case this ever happens to anyone else.

No need to adjust carb. I left the jets in it, that I had put in there tuning with the backwards piston, and it fired up second kick.
The only difference is I had my idle jacked way up, screwed all the way in, to make it run. Putting the piston in correctly solved this issue and now I've backed out the idle screw and I have plenty of adjustment there now.

A repaired plated cylinder, a piston kit, and gaskets and the 86 KDX 200 runs absolutely amazing now.