help!!!

[pjensen]

I have an '90 xr 600. It ran and started great when I first bought it about a year and a half ago. One day it just died when it was at idle. No sputter at all, like there was no spark. Soon this happened a couple times per ride. Then it started to have fits of REALLY hard starting. It was completely random, fall or no fall, hot or cold, anything.

I also have a '96 xr 600 which runs perfectly, and I tried swapping a few parts in an attempt to locate the problem. It (the'90) has a strong spark, the spark timing's good, valve clearance is good, and I've tried switching the carb and plug with the ones from the '96.

A less minor problem, the '96 seems to have much stronger snap off the bottom. It has a 155 main, 65 pilot, stock air filter and a big gun silencer. The '90 has a K&N filter, a supertrapp, a 160 main and a 65 pilot. could it be just the pipe that makes a difference?

Any good ideas? It's driving me nuts, any help would be greatly appreciated.

[bhoth]

You may have an intermittant problem with the stator coil. I had an 85 XR600R that was doing the same sort of thing you describe. Finally I decided to just replace the coil and the problem was solved.

Using a meter to test the coil, it always said the coil was good so It took me a long time to just replace the coil and be done with it.

[Moredesert]

One more thing you might look at is the kill switch, you could have a short. It does sound like electrical problems. On my 600 the spark pulg cap got very loose and caused a miss at times. All my starting problems were jetting but if it ran good before it most likely is electrical.