I took a short ride last week in town, and suddenly, my XJ750J started missing out. I turned off the main road to a sidestreet to go home. I was doing about 20 mph when it just died. I got it restarted and had this happen again until I got her home. When I pulled in, I hit a very wet spot in my yard from some wet grass and tree limbs that were just hauled away the day before. Of course, I went down.

When I got her in the garage, I checked the spark plugs. 1 was OK, 2 were darkened "carbon fouled" and 1 last one was oily. The oily one was on the side I fell on. I put some HEET in the tank thinking it might be moisture. Also cleaned all of the plugs ( I have not yet changed them since I got her last month) It ran fine when I started her the next day.

1. Any ideas what would cause this??
2. Could the oily plug just been caused by my falling down???

Thanks

Oils shouldn't get to your plugs just by falling over unless you left it lying down for a day or so. Oil shouldn't get past the rings unless they are cactus.

Could simply be oily cos your plugs are breaking down and not firing correctly.

Whack some new plugs in and see how it goes.

Check your air filter for signs of oil. Remove the filter and look down in the box. If you find any then check your oil level. If it is high this could be part of your problem. The oil can flow back into the filter box through the vent tube if the bike is on it's side. It can also be sucked into the airbox if high enough. This would cause the cough you experienced. Next thing to do is drain the oil and smell for gas. A leaking petcock can push the oil level up as gas slowly fills the crankcase. Common problem on XJ's. Rebuild or replace the petcock along with the oil, filter & plugs.

Not to mention the fact that gas-diluted oil has basically zero lubrication qualities...