Not on the DS.......this is happening on Daughter's Kawasaki Lakota 300.
Was getting hard to start, pulled plug and it was fouled pretty bad with carbon.
Put new plug in, properly gapped it, fired right up.
Went riding Saturday for about four hours, she said it died at least a dozen times. Would start right back up. She also said at times it was like she was loosing power in 4th or fifth gear, like it was bogging, then would die.
I rode it, seemed to do fine, did notice a high pitch sound coming from front of bike twice (almost sounded like 2 stroke) lasted for only a second or two under hard acceleration.
When revving bike hard in nuetral it produced a little black smoke.
I pulled the plug and that new plug had carbon build up on electrode, tip and first thread or two.

Any ideas what could be causing these symtoms?

 

Carbon fouling from a chemical standpoint should be caused by burning oil. But in reality I have had what I thought was carbon fouling on a rich carb setting also.

Are you calling it carbon fouling because it looks black and dry?

Also, black smoke speaks to a rich condition..............burning oil creates blue smoke. What has changed that might cause the bike to be running rich?


Maybe a better question would be; what things can change (externally and internally) that would cause a motor that has been running fine to, under similar circumstances, suddenly become rich?

 

Do a compression check. I bet you won't like the numbers.

 

DS nut, yes the plug was black. Had been running fine, no issues, no change in altitude etc.
The only thing I can think of is, a while back, I found the intake boot coming from the air filter had came off the back of the carb a little. I fixed it and forgot about it. Maybe she sucked some dirt into the carb??

Is there any harm in shooting some carb cleaner into it?
Thanks,

 

I have had both on 1988 Kawasaki Bayou 300:
1) engine dies.......took it to 3 different dealers and the 3rd replaced the ignitor box in the rear, it fixed the problem and has never died since

2) carbon on plug.........I still have the problem, dealers have no answer (except it old) I ended up buying a box of 12 plugs and replace as needed. I can go about 4 to 5 trips to the lease before i end up replacing it. Same thing, pule the plug and it has carbon build up, replace and it starte on first try. I have just learned to deal with it. It is a very old atv but it's gone through 2 kids and I still use it, the engines is very smooth.

 

I think it is dirt in carb, do not have tools for the khein carbs or I would take it apart.

Give me some opinions, would it hurt anything to spray carb cleaner in the carb??

 

Regarding the fouled plugs - this is happening because of a weak electrical system. Figure out why you're getting a weak spark and you won't be leaving a trail of spark plugs anymore.

 

This is an excellent post. I have experienced this as well. Weak spark can simulate a rich condition..........at least as far as symptoms are concerned!..........even when its not[img]i/expressions/face-icon-small-smile.gif[/img]

Weak spark will manifest itself the most when you are trying to start your machine. It will flood very easily and unburned fuel will backfire if you give it too much throttle at startup.

Ron