My friends Raptor 660 and it will run fine for a while and then it will spit and sputter a little and die. After a littel while it will start again we pulled the sparkplug and cleaned it and run it again till it quit and then pulled the plug and it was barly ghost white on the tip. When it does quit it is not that hot. It did this the last time it ran out of gas but after a while it started runing again and ran fine until it got low on gas again and started doing the same thing but that was yesterday and it has not starting fine again.

From what I know everything is stock, the only thing is in the pipe conectors below the muffler is gone so it leaks there and next to the head the outside pipe right before the heat guard it leaks there also I don't think it leaks much but would this be enough to cause it to run bad lean?

Also is there a fuel filter per say that could get cloged up to starve the engine of fuel?


Thanks for the help.
Derek

 

First of all, don't reuse spark plugs. Although you may think you have properly cleaned the plug there could be buildup, burnout, incorrect gap and numerous other problems with a used plug that you don't see when "cleaning" it. Always replace your plug with a fresh one if you suspect it of being a problem. They aren't that expensive.

After replacing the plug with a new, properly gapped plug, try running the bike for a bit and recheck the plug to get an idea of the air fuel mixture. I would not expect a full stock bike to be running very lean simply from missing a couple of exhaust seals and there are no fuel filters on a stock 660 save a small screen on the petcock. Let us know if you don't get it figured out.

~HoundDog

 

I've seen these symptoms on a raptor of our group, believe it or not it was loose battery cables, worth checking them out to rule out at least[img]i/expressions/face-icon-small-wink.gif[/img]

 

I would also check the adjustment on the intake valves. It could be they have little or no clearance cold and are staying slightly open when it warms up.