I was talkin to my spark plug and thi is what it had to say...

[EX LONERIDER]

http://img228.imageshack.us/img228/3299/plug004ry5.jpg
http://img228.imageshack.us/img228/4458/plug005vg7.jpg


has a nice chocolate brown burn to it. seems like i hit it dead on as far as the jetting goes but i still have a very slight stumble. the mods done to my bike are on my signature. this trip i ran 1/2 91 octane, 1/2 110 VP leaded....... yea, leaded and ran *****in!!!!!

mostly... its when the bike has no load to just under 1/4 throttle.... my best guess is a pilot? what do you guys think? i figure if i go up one size it should fix the issue.... but im looking for reassurance in others opinions.

[Flynbryan19]

Possibly the pilot. More than likely that they throttle position it is your pilot screw.

[NacsMXer]

The 1st pic looks good a nice tan color (ideal) but the 2nd pic for some reason looks a lot darker/on the rich side. Maybe it's the lighting in the pics playing tricks. If it stumbles when you get into it you could be slightly rich. It doesn't really show signs of running lean so try bumping down the pilot or leaning out the fuel screw.

[EX LONERIDER]

yea... the lighting is not playing tricks. for some reason or another, one side is darker then the other. the only thing i can figure is maybe the way its burning inside the cylinder. i think i may be on the rich side on my pilot screw. i have it set to 2 3/4 turns out. imma go back 1/4 turn and see if it helps.

other then that, the bike runs perfect. so imma guess the pilot screw is where my issue lies... thanks for the input guys.

[Big - D Racing]

most all race fuel is leaded, it is standard. I run VP C-12 straight.

[EX LONERIDER]

didnt know that.... they do offer some unleaded race gas but i figured there might have been speculation so i wanted to be clear on it.:D

[Big - D Racing]

the only unleaded race fuel I know of it VP Ultimate 4. It is 100 octane unleaded. I am sure there are others but that's the only one I know of.

[EX LONERIDER]

yea... the place i whent to sells it straight at the pump or in a 5 gal can. they sell a 109 unleaded but im not sure what else. they had alot to chose from. didnt have time to see what else they offered since they were closing in 5 minutes. cool thing though since now i know where to go for race fuel :devil:

[AutoRoc]

VP makes MS103 and MS109 unleaded. Both oxygenated also and make good power. I run Torco 110 leaded in mine.

Plug doesn't look bad but like these guys are saying, maybe take a little fuel out. I'm tempted to hook my car's Innovate Wideband O2 sensor into my 440EX soon and see how rich/lean it is at idle/cruise/WOT... We'll see once it gets rebuilt! haha

[400exrapes]

Oh well in case you havent fixed the jetting this is what helped me in my jetting dilema.
Neutral-3/8 throttle = Pilot Jet
3/8-1/2 throttle=needle clip
1/2-WOT=Main jet

Wherever your problem is find out how hard your pushing the throttle and it will be one of those three.

[Eviltanker]

Stumbling at 1/4 is pilot being on the rich side. back up 1/4 turn and go from there.

[EX LONERIDER]

yea... it was the pilot screw. set it back to 2 1/4 turns and its fine now.

i still may have to mess with jetting... im thinking about goin to a uni filter and dumping all the extra stuff thats restricting the air flow.