OK... I just got an old clapped out old 200EXC. First 2-smoke since I was a kid so workin on them is a mystery to me. I cleaned it all up and ordered a jd jet kit for it. Here's the deal.... My Power valve was way out of adjustment.... The adjustable mark was below the bottom mark. I screwed the adjuster out till the mark was back where it should be or close to it. The deal is it was smoking like a cropduster at idle and just blasted smoke out the pipe when I rode it down the street. One trip around the block and I have black spooge dripping out of the tail pipe with a brand new pipe and silencer. Could this just jetting or am I gonna have to recheck the timing on the power valve too???? I am running 91 octane with Motorex @40:1. 180 main, JD blue @4th clip, AS 1 1/4 out 45 pilot...just what JD recommended in the kit.
Any help would be greatly appreciated.....

could be a number of things.

Do you know the condition of the topend?

May need to check the PV for proper operation and hook up.

What year bike?

it sounds like a top end is in order. Jetting is about right. Could also be a leaky main seal. PV wont make it smoke.

Mike in Fresno said:

that's right, still could be out of order though. we have been seeing a lot of that here lately...

well..I did a little bit of tinkering last night... went to the red needle @ #4 and that seemed to be a little better... then I checked the air screw and it barely changed when I screwed it all the way in so I dropped it down to a 42 pilot. started right up and seemed to smoke even less. Took it down the street and it died at the end of the block.... :foul: :banghead: :foul: Then I decided it was time to just push it back home and go to bed. I'll have to dink around with it some more tonight.....

cb60130 said:

check float height as well.

What year bike??

it's a 2001.

You know it's funny you mention float level...the other day I was dinking around and changed the main jet from a 185 to a 180 just by twisting the carb and removing the float bowl drain. Then my bike wouldn't start.... so I thought maybe the float needle was stuck.... So I pulled the carb all the way out and took it apart again.... blew a little carb leaner around and put it back together and she fired right back up. Last night I twisted the carb and pulled the bowl to change the pilot and put it back together. Now that I think about it.... it's almost exactly the same as it was 2 days ago.... Guess I'll take the carb out again and blast everything out again..