96' KDX 200 low RPM white smoke & oily exaust

What ratio are you mixing your oil/fuel mixture? Could also be your carb settings.

My bike smokes very similar to yours. I have an 01 kdx 200 which smokes pretty bad throughout the RPM range when first started. It's get better when warm, but always smokes more than I think it should (running smokeless oil at 32:1). When it's revved out and I'm riding in the upper range it doesn't smoke as bad until you start putting around again, but it always runs very strong regardless of smoke amount. I am pretty sure I have a bad crankcase seal and this could possibly be my source of smoke. It is possible your new crankcase seal was damaged upon installation? Even so, mine still doesn't have the stalling issue. I agree with heino, it could be the carb settings.

I run Yamaha oil 40-1, smoke when cold but then fine. Been running strong for 6 years, no top end needed yet. I'd cut back on oil.

Read the jetting thread before you start changing oil ratios. Simple jetting changes will clean up the burn and smoke less. Jetting takes a little time and careful thought but is not that difficult. Plus, you will like the way your bike runs when your done.

OK, this sounds familiar. I am having similar issues.

I live at sea level. I was using 40:1 oil (Spectro 2T synthetic). '96 200 H with FMF Rev pipe, new Boyesen reeds, stock carb, cleaned and repacked pipe and silencer, and fresh properly rebuilt KIPS.

Been trying to cure a serious lack of low end response, and excessive white smoking. I leaned my carb out to a 42 pilot and a 150 main. It ran fast but still no bottom end, lots of smoking, and wouldnt idle. I talked to someone at FRP who said "Whoa. Cut back to 50:1 with that oil. Go back to the stock jetting and start over.". Yesterday I went riding at 3000 elevation. Since going up in elevation richens your mixture, and so does raising the oil mix ratio, I left the lean jetting in. All I changed was the oil mix, to 50:1. oh yeah, I also tossed the Champion NC4 plug and put in an NGK B8ES. Here's how it turned out:

- Bike still smoked. But looking at several friends 2 stroke bikes in the cold morning air, they all smoked a lot.

- Bike idled nicely. Big improvement. It didnt hold idle before. Hmm. Maybe the fresh plug?

- Bike still had almost no usable power in the first 1/3 turn of the throttle. I rode all morning using the upper 2/3 of the throttle. BUT...

- on single track, I COULD crawl up steep hills and lug the motor down an incredible amount. It just kept going. I was amazed.

- if I tried to use much throttle though, it really had a hit of power, spun the back tire or wheelied (not good on a slow steep uphill). I learned to just go, like a tank, and never stop on a hill!

CONCLUSION: more jet work needed but clearly my jetting needs to be richer, not leaner. I can't imagine this will help the smoking problem, but maybe the 50:1 mix will do that. For the power band issue, I may also try a flywheel weight if I can find one. And I think a pipe change will help move some power to the lower RPMs. According to FRP, the rev pipe is not a good match for a novice rider doing mostly single track. I'd have to agree. :nod: Anybody wanna buy a FMF Rev pipe?