Fouling Plugs

[trickster19]

I just bought a 2005 kx100 on saturday and today i fouled 2 spark plugs. So i was thinking that when the people put gas in the bike they mixed the gas to rich. I bought the bike used and it has about 20 hours from the previous owner. I just clean the air filter yesterday. It has never been jetted. What do you think

 

[elliot-cr133]

you're probably right...

 

[stevied125]

You are right!! I just bought a 2005 YZ125 a little over a month ago. For break in purposes they mix the gas 32:1 but after the first tank they said mix 40:1. I fouled a plug on my first tank also

 

[DLHamblin]

I just bought a 2005 kx100 on saturday and today i fouled 2 spark plugs. So i was thinking that when the people put gas in the bike they mixed the gas to rich. What do you think

Its impossible for us to guess without a little more info.

Is the bike running stock plug and jetting or has the jetting been changed (being as its a 2005 its either a left over and new you just bought or its used). If its used how many hours on the top-end? Is the air filter clean?

There are a number of reasons it could foul.

If in doubt; change the pre-mix. Just remember the less oil in the pre-mix the richer the fuel mixture is. So 32:1 is actually a leaner fuel mixture than 40:1.

 

[trickster19]

Ok i bought the bike used and it has about 20 hours from the previous owners. I just clean the air filter yesterday. It has never been jetted.

 

[Xtremesports445]

you say previous ownerS. Was there more than one or is that a typo?

 

[trickster19]

it was a typo

 

[Xtremesports445]

ok, so then do you know what the premix ratio is that's in the tank?

 

[xr100ider]

Just putting this out there...but i think more people generally go with Rich and Lean having to do with the oil rather than the fuel.

Just to avoid any confusion....

 

[DLHamblin]

Just putting this out there...but i think more people generally go with Rich and Lean having to do with the oil rather than the fuel.

Just to avoid any confusion....

Thats why I mentioned it, to avoid confusion. If your bike is running rich (fuel mixture) and fouling plugs; going from 32:1 to 40 or 50:1 actually makes the bike more rich (fuel mixture) and prone to fouling plugs.

Most 2-stroke oils are ok to mix from 16:1 to 40:1 (with some of the synthetics supposedly able to mix even higher ratios) as long as you jet accordingly.

The richer fuel mixture makes the combustion temperature less; so the plug tip temp is less and will foul easier.

 

[budhoot]

i mix my bike 32:1 and its a 2002 yz125 i never foul plugs but if you dont putt around on em you shouldnt foul em or atleast i dont guess thats just that kawasaki lol........

 

[trial_07]

My kawasaki never fouls a plug at a 32:1 ratio.

 

[snb73]

Pick a ratio, then jet it.

I would suggest 32:1

 

[hks308]

yea, just keep it on 32:1. i was running around 42:1 foulin plugs none stop. now that im 32:1 i have never fouled one yet.