We just rebuilt the top end of our 2007 KX 85. It ran great for the first 30 minutes of riding then suddenly started making a weird noise. We've changed the plug, took off and re-connected everything, cleaned the air filter and it's still making the weird noise. Almost like a rattle or whine noise. Any ideas?
No, once it was put together we didn't do anything else. Water level is fine and oil is fine. We have someone coming to look at it tonight. Hopefully he can figure it out.