I'm new to these forum things, but I just picked up a 2009 klx250sf today and I bought it not running because I was getting a killer deal anyways I brought it home went through it and got it to fire right up rode it around a little and noticed there was a loud rattle in the motor,(cam tensioners) so I looked up and ordered a Krieger manual one, just waiting on that but when I was riding it 3rd gear started popping so I went back home let it sit, checked the plug and it was getting no spark so replaced the plug and still not getting a spark, anyone know why?? Thanks!

 

Check you kick stand safety switch and wires for a cut or lose wire, common problem.

 

I checked that and nothing still, I even bypassed it

 

First, check the basics-battery terminal clean and tight, verify that the main ground terminal(it's located on the l/h side of the engine case above the front sprocket) is tight, check the 20A fuse(under the seat on the starter relay), check the harness connectors for the ignition module(under the l/h side cover) and the pick up coil. If all of those are good then I would suggest you download the service manual https://www.kawasakiforums.com/forum...manuals-37525/
and go to the electrical section page 16-45 and follow the flow chart to isolate the cause of the problem. You will need a volt meter/multi-tester to check resistance and voltage on the harness.
It's a little time consuming but it's the only way to accurately test the system

 

Tighten up the plug wire? Maybe take it off and take it apart and screw it back together. Or replace the wire with some new stuff, it's cheap.