spark plug fouling

[woodsrider823]

Hey I filled up my 5 gallon gas tank with premix golden spectro 50-1 ratio. I used most of it to fill up the tank on my kdx 200 and I rode it about 5 times throughout that week. I then stored the bike for a couple of weeks, put the remaining gas in the 5 gallon that i had left over and it wouldnt start. I put a new plug in fired right up, turned it off wouldnt start again, new plug same thing. Any ideas on why i am fouling plugs now or any ideas on what to do? thanks

 

[lepper]

Make sure you mix up that gas oil mix real good... the longer it sits, the more it separates.

 

[oldturtle]

I would try process of elimination. First make sure that bike starts easy and runs correctly with fresh premix. Then next time out use Stabil gasoline stabilizer for the left over gas and see if this solves the problem. Premix goes bad faster then straight gas and Stabil will keep it better for longer period. Another thing to try is draining the floatbowl before parking for over one week. The first place bad gas starts mucking up things is usually in the pilot jet and draining float bowl will keep pilot clear.
If none of the above helps then I would think your jetting may be too rich, or air filter may be dirty, or spark arrestor may be partially plugged.

 

[adam728]

I would try process of elimination. First make sure that bike starts easy and runs correctly with fresh premix. Then next time out use Stabil gasoline stabilizer for the left over gas and see if this solves the problem. Premix goes bad faster then straight gas and Stabil will keep it better for longer period. Another thing to try is draining the floatbowl before parking for over one week. The first place bad gas starts mucking up things is usually in the pilot jet and draining float bowl will keep pilot clear.
If none of the above helps then I would think your jetting may be too rich, or air filter may be dirty, or spark arrestor may be partially plugged.

All good info, except that premix does not goes bad faster than plain gasoline. Many premix oils have additives that act as a stabilizer and extend the life of the gasoline. Still, if I have some sitting around more than about a month I dump it in the Jeep and get some fresh stuff for the bike.

 

[oldturtle]

.....premix does not go bad faster than plain gasoline....

You could be right on that Adam but since all the lubrication for top and bottom is in the premix I just worry much more about fresh premix in KDX and Banshee than I worry about fresh straight gas for 4 strokes that have seperate and independent lubrication.

 

[Green Hornet]

IMO I don't think the fuel going bad is the problem. You got SPARK?????

 

[woodsrider823]

yea im getting spark and when i put a new plug in it fires right up but then once i kill it, it wont start again.

 

[rubbersidedown]

I can put my old pre-mix in my Jeep? sorry to de-rail.

 

[adam728]

I can put my old pre-mix in my Jeep? sorry to de-rail.

I've always thrown old premix in what ever I am driving at that time. Usually it's like a gallon or 2 in 15 gallons of gas, so it really doesn't have any effect. Running 400 to 1 premix doesn't hurt anything.

As for the bike wetting plugs, are you running the right heat range plug? Carb clean? Float set to the proper height?

 

[woodsrider823]

yea everything is the same as it has been i didnt change plugs or anything it just started fouling plugs, really weird

 

[John Harris]

Maybe I missed something here, but sounds like your air filter may be stopped up. Clean yours or better yet get a new one--sometimes the old ones just mat up in the pores especially if incorrect oil was used. Cheers John