1992 kdx200 power valve govenor hose

[Caleb#Mx92]

Hello I am in need of help with this issue I have a 1992 kdx200 that I have been working on I cleaned the carb and have about the stock jetting with a 150 main jet and a 48 pilot and 32:1 mixed. I have the bike tuned to my best ability and it runs good and starts good but the bike is boggy in the first two gears and clears out later on once in the power band. The bike smokes excessively but runs good and I noticed that around the govenor hose on the govenor power valve side it is leaking a little smoke and the hose is not sealed good. Is there a way to seal the hose or do I need to clean the power valves and if so is there a way to clean the power valves without taking the motor half apart.

Thanks

This is where the smoke comes out a little bit

20250711_192942~2.jpg (1.22 MiB) Viewed 244 times

[SpruceItUp]

If you're seeing smoke there, you need to replace the seal along the powervalve shaft.
That black hose you're talking about isn't a hose, it's more of a 'cover' to protect the rod to the governor from dirt and debris.
If you haven't cleaned the powervalves on this bike before it would be a good idea. They are known for eating the teeth on the gears when they have a lot of carbon build up on them due to them being aluminum and not steel.

To clean, I believe you can get away with just taking the head off, though I believe the main (middle) valve can be a bit tricky to reassemble without removing the cylinder due to its positioning on the bike. You'll need to get a new head gasket anyways, so just get a cylinder base gasket as well and remove the cylinder. It'll make your life much easier. It also allows you to inspect your piston and rod to make sure they're doing alright (never hurts).

I'm attaching a picture of the parts fiche for the top end of this bike. The seal in blue needs to be replaced if you're seeing smoke from that area. I highlighted the other two seals in the powervalve system in green that wouldn't hurt to be replaced since you're already in there. Plus one is not sealing, so there's a good chance the other two are on their way out as well.

Finally, when you go to take the governor rod (vertical from clutch case) off of the rod that actuates the power valves, remember the nut is a left hand thread. It is reversed compared to all of the other bolts. You can break the governor if you try to go the other way, so be careful!

P.S. If you want jetting help, go read this thread, it is immensely helpful for getting your jetting spot on: viewtopic.php?t=1156

[Caleb#Mx92]

Thank you so much I will look into it and see what I can do I figured a little seal would need replacing and plus the power valves definitely need to be cleaned because whoever I bought it from probably didn't do so. I will also mess with the jetting to see if it will help it run better and go from there.

[SpruceItUp]

Sounds good! Keep us updated and good luck!

[Caleb#Mx92]

Thank you I appreciate it!