Shifting my tuning focus...

I have been chasing around a surge in my recently aquired XR600. I thought it was a lean condition, so I went and got some richer jets. It has the same surge and poor running charactersistics after using a broad spread of jets. Today I put it back to how I got it; still popped and missed with a little black exhaust. I then lowered the needle from the 3rd to 2nd(from top) position, and it got worse. Here is a link to my post in the jetting foum: '95 Lean Jetting

I am trying not to have tunnel vision and focus only on the carb. Now that I've ruled alot out plus my bike's unresponsiveness to jetting changes, I am frustrated and figured I'd ask in here for any possible XR600 nuances I may have overlooked.

What about the coil? I had a bad coil on a bike that behaved properly when the bike was cold, but as the bike warmed up would begin to cut out.

Ignition or cam timing????

I was actually starting to suspect the ignition as that and the cam are the only things I havent checked. The engine supposedly has been rebuilt, so I suppose the cam could be off or have a slotted sprocket that slipped. I'm waiting on a Clymer manual so I'll have a reference when I dig in.

I assume I check the coil for a specific amount of resistance? Or is there more to it?

sometimes good coils test bad, your best bet is to switch it out with a known good one. Good news is lots of years used that same coil. I'm guessing '88 thru 2000.

Thankfully I dont even need to go that far. Today I was repairing my sparkplug boot(a prev. owner ripped the silicone pretty bad) and I had to pull the tank to wrap tape around the boot. I did that and figured I'd make sure the spade connectors on the coil were alright, and low and behold one of them was so loose it was rattling on the post bad enough to make wear grooves. I pinched down the connectors and put some dielectric grease on them and went for a spin. Dang, just like I KNEW an XR should feel. Thats right, 3 weeks of headache for a loose connector. Runs like beast now :thumbsup:

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now