Piston... Is this too lean or Rich.

[Nick110]

Help me out guys, is my quad running too lean or too rich.

http://i44.photobucket.com/albums/f29/nick110/DSCF0225.jpg
http://i44.photobucket.com/albums/f29/nick110/DSCF0227.jpg
http://i44.photobucket.com/albums/f29/nick110/DSCF0228.jpg

[d3ktrix]

Did u clean it? or is that how it came out?

[Nick110]

thats how it came out.

[d3ktrix]

EDITED:

Whats your jetting/mods?
What did it run like that made u question it?

[tfuchs]

Looks like lead deposits from race gas

[Nick110]

Originally posted by d3ktrix
EDITED:

Whats your jetting/mods?
What did it run like that made u question it?

My mods are Rossier full system, uni filter, no lid, and 02 crf cam. My jetting was set to rossiers spec for the full exhaust which I think is 48 pilot 160 main and HRC needle on 4 clip.

It felt like it ran great, Im just tearing my motor down to fix the tranny.

[d3ktrix]

Race gas correct?
Thought something was really wrong at first but then I forgot race gas turns everything white :P

I'm not sure about the effects that race gas make, but it looks like a decent amount of piston wash to me. I'd say your pretty good, I could be wrong though :P

[400exrider989]

looking at your plug is the only way to get a perfect reading

[pro-rider46]

what type of race fuel are you running? and the plug is not the only way to tell how it runs, thats just the easiest instead of tearing the whole thing apart, and thats the stocker right?

[400exrider989]

plug tells you whats going on and how everything is doing inside so that you dont have to tear it apart

[pro-rider46]

Originally posted by 400exrider989
plug tells you whats going on and how everything is doing inside so that you dont have to tear it apart
exactly, but looking at the plug is not the only way to tell

[4bidden]

I run race gas and I've NEVER pulled a piston that looked like that.

[bloodmoney23]

well ive never ran cam2 or nothing in an ATV but Ive ran plenty of it in my car and everything up to the tip of my exhaust looks like that. Race fuel does leave white instead of black exhaust. If you were running normal fuel that would not look good. If you are indeed running race fuel than you are fine. and if that is the stock piston then it would be best to stop running race fuel. Get a high comp piston then run it. By the pits in the top of it looks like it may not have much left in it. (in the pic its pitted bad) and by the pic i can gaurentee the bottom of your plug is white as well.

[Nick110]

Thanks guys, I ran U4 in the beginning of the season but then switched to C12. Its a Wiseco 13.5.1. I will be getting a new piston over winter.

So I shouldnt change the jetting?

[bloodmoney23]

No as long as the bike is running how it is supposed to and its not running hot, or popping on decel and still have a good midrange and all then your jetting is fine . You would def be able to tell if your jetting was off. Just pick up the new piston and keep doing what your doing. If anyoen else has better advice let him know. Like I said, I have my experience with cam2 in import cars not atv's even though they should be the exact same concept.

[k265r]

u4 is not good for aluminum i have had to replace carburetor parts from u4 eating away the aluminum.

[eastside 400]

160 seems on the lean side to me, ive ran C12 all year long with correct jetting and my baldwin 14:1 piston is black on top but the combustion chamber and valves look like yours, white/green from the dye