So I have a 90' bayou 300 4wd. The problem I have is when it is starting, when it I turn it over with the electric starter all it does is turn over and over. I pulled the plug and I am getting terrible spark but can't diagnose why. When I ground the plug to check it, it will not spark UNTIL I release the start button and it only sparks once or twice. This is something that seems to happen in the winter when the garage is cold, but if I get it running, it will run perfect all day even when starting it and stopping and along the trails. It is just that sometimes I go weeks without starting it and it is almost impossible to get going when I need it especially when the snow is coming and I need to plow with it...any ideas? Coil? Rectifier? It has a new battery so I know its not that

 

My 2001 Bayou 300 had similar problems. Little or no spark until I let off the start button, then it would put out one or two bright arcs. It seemed to start and run better during warm weather. A Kawasaki Tech told me to use a hair dryer and heat the CDI Box (easily accessable from the back of the quad and against the back of the battery box). While this isn't foolproof, it will sometimes result in a stronger spark, or the starting of the engine. Factory Service charged me $250 in labor, plus $300 for a new CDI. If the heater trick works, you can replace it yourself much cheaper, and without having to remove body cowlings. Hope this works for you! Jim

 

I also had the same problem a couple of weeks ago, I systematically went through and cleaned all the terminals from the CDI to the starter coil, including numerous solenoids etc. and worked fine after. I found that mine had corroded quite a bit with what i can only explain as white dusty/grit all over the terminals. hope this helps.