Guys,
Another stupid question. I fired my 400ex (it was actually warm enough) for the first time since like September. It sputttered at first, which is to be expected. I got it to idle a little bit and figured I would run it down the road to blow the 'funk' out. It kept backfiring for like the first minute or so then it quit and ran like a scalded dog. Does that mean that my timing is potentially off, or could it be a function of non-use or bad gas? Any help would be greatly appreciated.
Tom

 

I would say your gas i bad from the back firing or sputtering, but that is my opinion. I'm not an expert.

 

if the gas is that old, it was bad. i would replace the gas.

 

Thanks guys. That is what I thought. I didn't put any stabilizer in there. I will put some new hi-octane.

 

If you plan on letting it sit, for more than a few days, with out being started, you might want to get in the habit of leaving the float bowl dry, while it sits.
Either turn off the gas, while idleing, when youre done riding, and let it die ( itll take a minute or so). Or shut it off, turn off the gas, and drain the float bowl with the screw on the bottom of the float bowl.
This will keep the carb , and the jets clean. Its the constant evaporation, and refilling of the carb float bowl, which condenses, and thickens the deposits.
Add the stabil, or other stablizer, to new gas..it wont do a thing for gas which has already gone bad.