Hi! i am new to this forum and i have a kawasaki 300 1986 2x4.I was driving it yesterday when suddenly bam...I couldn't drive over half throttle. It runs normal,and i can rap it out half throttle but after that it seems to stay half throttle ,even if you push the throttle all the way back!And it idles and runs great other than that!I just had it overhauled for $500 about 1-2 months ago.Please reply as soon as possible! Thanks...TBK Right now it only runs 30-35,,,normally it runs about 50-55 mph.

 

The most likely thing is dirt in the main jet. Remove the float bowl and blow the jets out with compressed air, holding them to the light afterwards to ensure they are clean. If that doesn't cure it, the CD piston may be sticking, or diaphragm holed. Or the CDI starting to fail, dropping the revs that the limiter kicks in at.

 

Definitely sounds like a fuel delivery issue...clogged jets as mentioned above or something in tank...also, ensure your tank vent is clear...

 

Okay thanks i'll try that!I'll probably pull the carb off and post back tonight!Thanks TBK

 

Okay, i cleaned the jets and put carb back on.It sounded the sameSo what should i do next?

 

Really???No reply yet???

 

Should i get a new CDI???

 

Have you checked the CD piston and diaphragm? If that is OK I would check what voltage the regulator is putting out with the engine running, if you get more than 15v across the battery it could be cooking the CDI. If that is OK, start with the cheap stuff, like a new plug, then a new coil, before going for the expensive bits like a CDI.

 

We put a new cylinder and piston in it when we overhauled it.And we put a new regulator and carburator on it a few weeks agoWe have a new spark plug in it and i'm going to check the fuel tank pet **** filter.

 

Can you run it at full throttle for 30 seconds, then kill motor (while at full throttle) and post a picture of the plug? If this were electrical the plug would be wet as you're dumping fuel in & it's not being burned...if the plug looks normal or light then I'm still at a fuel delivery issue...