89 kdx200 power issue

[dboots77]

I just got the bike last week and starts great but had no power in first and second, and my air screw is turned 10 TURNS OUT. This can't be right, but I'm new to two strokes and this kips system and I just don't know where to start with this.

[dboots77]

Also it has just had the top end done. And everything else is stock other than a fmf pipe and no airbox lid to my knowledge. Another thing when I pull the choke up it Boggs the bike way down until it dies at idle I don't get it

[KDXGarage]

1.5 turns out on air screw

stop lifting the choke after it is running??

[dboots77]

I dont I was just going over the bike when I got it and saw the starting it on the choke want happening so from curiosity I pulled the choke right after I started it and it would die if that's normal great lol I just thought it was weird. On the air screw I turned it all the way in then out 1.5 turns and it idles super low and when given some gas it seems rich I think I'm assuming this is a jetting issue but no matter where the air screw is my low end power is horrible pretty much not there when I get into third and so on the bike runs great it's just first and second is powerless.

[Julien D]

low end power doesn't relate to what gear you are in, but what RPM you are running. Given that, your description of the problem is going to be very difficult to diagnose. I'm pretty sure at 10 turns out, my airscrew would no longer be seated in the carb.... Something wrong there.


Things to check

Proper power valve operation
Carb and all jets are clean
Jets are appropriate size for elevation / temps
Compression is within usable range
No air leaks present

[dboots77]

Ok that's my plan for tonight I was planning on pulling the carb for cleaning and ill have to look into how to check if my power valve is working correctly. What I mean I guess is it'll accelerate to like 1/4 throttle and then be flat like that's all it has in that gear, and that's how it is until I hit 3rd then the bike really wakes up

[Julien D]

Sounds like you might have a busted power valve. On the E bike, the way to verify is to pull the pipe off as well as the small plastic kips cover on the RH (as you sit on the bike) side of the engine. Under the cover, you will see a rod protruding from cylinder just below the head. Pull that rod out by hand and watch through the exhaust port to see if all 3 valves inside there move in sync with each other.

[dboots77]

Ok I'll try that tonight. If that is the case I have to pull motor to fix it don't I?

[Julien D]

Not necessarily. You can get to everything with the motor installed, but it is a lot easier if you at least pull the cylinder and head and put them on a bench. If you do have to remove and replace, be aware that the nut holding the actuator arm at the end of the governor rod is left hand thread, and the rod must be supported when removing the nut otherwise you risk breaking the actuator inside the clutch cover.

[dboots77]

Ok ill have to look at it tonight so I can fully understand what your saying in regards to supporting the rod during removal

[Julien D]

There are plenty of threads here on the subject, as well as a number of videos out on Youtube that outline the process.

[dboots77]

Already looking thank you for your help