96 KDX 200 No Top End Poping And Breaking Up

[jayv70]

Dusted off the ole 96 KDX 200 for my nephew to learn how to ride a big bike, it has sat for about two years.

It fired right up as usual, took it for a little spin and it would not get into the power band or rev over half throttle properly (felt like a real lean condition). Brought it back to the barn and went through the carb, replaced the main jet (even though it looked fine), noticed the carb boot was a little dry rotted (replaced it, Boysen not stock) Put it all back together and it still does the same thing (although now it is not as bad). What else could it be? Gas in the tank is new, not bad it is almost as if it is staarving for fuel over half throttle.


Thanks for your help.

 

[reepicheep]

Goo'd and glue'd KIPS assembly? Can you see it advance proportional to the revs?

 

[samiam]

If you are certain that the carb is completely clean, the powervalve is probably stuck from sitting so long. When the powervalve on my '96 was dirty it would not rev out until the motor got good and hot - hot enough to get the spooge and sludge around the valve parts melted enough to free up. This could take up to 5 or 10 minutes from a cold start.

 

[jayv70]

The carb is indeed clean. Cleaning the power valve does not look like a very easy job, are there any tricks to doing this that might make it an easy job?

Thanks,

Jay

 

[sr5bidder]

you can take the round sloted cover off the left side of the cylinder and put a 10mm socket on it and turn counter clockwise and then back clockwise. if it take more than a gentle turn of your wrist to move then I would suggest disassembling cleaning...

it may be really stuck so do not use force

Once you have turned it ccw it should snap back to the closed cw positionif you pull the socket off

the assembly is viewable if you take the exhuast off and use a flashlight

 

[reepicheep]

And if you do try and take that nut at the top of the shaft off, there is a flat on the vertical shaft you can use to hold it while you remove the nut (which may, from memory, have backwards threads). If you don't support it there, you can hurt the advancer assembly or break off a hard steel pin, which can get into the rest of your motor.

 

[liven07]

Take the float bowl off with the fuel line connected and push up on the float to ensure there is a steady stream of fuel coming out. If the fuel looks good it is most likely the kips.

 

[liven07]

Also don't forget the simple stuff like the spark plug and the kips you should be able to see it move if you take the cover off. Will move about half way through the rpm's, not at low rpm's.

 

[julien_d]

The kips is not too bad to clean really. If you don't have a service manual it's certainly worth the investment to buy one. It will help you make sure you have the kips stuff timed properly when you reassemble.

My vote goes to KIPS too. Sounds much like the symtoms from the valves being stuck closed.

J.