Spark Plugs are fouling, what to do?

[badbanshee01]

Hi,

 

A couple weeks ago I jetted my quad with a 320 main and needle on the 4th clip. Mods are in my sig. However, since then the temp. has increased about 10 degrees. When I ran it today i fouled a set of brand new spark plugs after about a minute of hard riding. I'm going through plugs like crazy so what main should I step down to? I don't think I should have to rejet for a 10 degree difference so maybe I was rich before and now it just made it richer? Thanks alot

[2003LimitedBanshee]

I would have guessed you would be around the right jetting, but probably a touch fat. Plus, if you are fouling plugs that fast, you must be jetted too rich, and the warmer temps revealed that. Is it fouling both plus? If so it is most likely jetting, but it could be dirty filter, weakening stator (weaker spark), too rich oil ratio etc, but likely jetting. If it is just fouling one plug it could also point to a bad plug wire etc.

[badbanshee01]

One cylinder would stop firing while the other would still go but both plugs were pretty black when I looked at them. I run 24:1 oil premix with yamalube which is too rich I know. I plan to start running 32:1 so should I try that before rejetting or still go down one size on the main? Thanks alot

[banshee tuner]

Try 40:1 mix ratio and jet your mains no larger than 300's at sea level.

[onz]

Try 40:1 mix ratio and jet your mains no larger than 300's at sea level.

461975[/snapback]

 

thats what i run..24:1 way to rich

[FIRST BANSHEE]

I would try some 300's and move the clip up one to the middle.

also if your are going to change your oil/fuel ratio, do it before you rejet. you'll be adding more fuel when you change your mix.

[badbanshee01]

Ok, so I changed my mix to 32:1and installed some 310 mains. It started right up and ran beautiful, no oil dripping out of the silencers like before with 24:1. After about 10 minutes of riding I decide to check my plugs. The plugs were used ones that were black but now the entire porcelin color was white So, how big should I go up on my main and the needle? It ran great but I'm sure I am lean THanks

[badbanshee01]

I just tried some 330's and it ran about the same as it did with the 310's. The plugs had a darker color but were still starting to turn white on the porcelin. I could go richer I think since it doesn't seem rich but I'm not sure. the biggest I have is a 340 and I'm getting pretty close to swithcing to it

[banshee tuner]

It's sounds to me like you might have an air leak, what is your elevation.

[banshee tuner]

You also might not be getting the right amount of gas to the carbs or your float height might be wrong.

[FIRST BANSHEE]

I just tried some 330's and it ran about the same as it did with the 310's. The plugs had a darker color but were still starting to turn white on the porcelin. I could go richer I think since it doesn't seem rich but I'm not sure. the biggest I have is a 340 and I'm getting pretty close to swithcing to it

463699[/snapback]

sounds like your close. I would go up one size at a time untill it burbles a little then back off one. then start on the needle

Edited January 24, 2006 by FIRST BANSHEE

[badbanshee01]

I just did a wot test with brand new plugs, ya know where you smack brand new plugs in and run it wide open for 10 seconds then shut it off. Well I did that and when I got done I looked at my pipes and they were glowing red for about 6 inches after they exit the motor This scared the shit out of me I don't know if this hurt my motor any from overheating. Anyways aobut the plug it has a nice medium brown around it but for a quarter of the way around it there is a twist in it.by that I mean it comes up toward the end of the porcealin and it also gets black their. I have read about one guys plug doing this but nobody knew why. So, I guess this means I am good on my mains, man 330's seem high but they work. I'l try messing with the needle now. It could idle all day, it's perfect. Thanks for all of your help you have given me through this hassle