Hi sorry for my poor english but i 'll try.My quad was perfect last year but i decided to put a new air intake on.Now i have some problem to jet it.I explain my problem. The quad run good at idle but when i push on the throttle ,during .5 second it stop he misfire if i can tell you like that just loosing big power .i push again and he is able to cross over the misfire.to 50%throttle.and 100% is perfect.

Idle=Good idle
0to¼ OKAY
¼ to 40%.Misfire just when the needle come in.
40% to 100%throttle ALL is perfect.
My spark plug is more white than dark.Little brown.Last year it was dark.but now....??

Does is the pilot jet?
Needle jet
Jet Needle?

Is there a sign im too rich or lean? spark plug seem perfect?


Thank you i will post more info...

thank you so much

 

I would clean the carb,make sure jets are clean,if has old gas I would drain/siphon out. Fresh gas and use Marine Stabil,best for ethanol gas.Carb probably just varnished up,spark plug whitish color is usually lean condition,not getting enough fuel. If what I understand that you have installed a different air intake and filter?? Then could need a main jet increase,plus you can drop the slide needle clip one position (raises needle to allow more fuel at low/mid range) Welcome to the forum! OPT

 

Yes i already put new fuel .Iwas jetted 175 on the main im 185 now.But the problem is not at the main jet because the power is good a this level...i clipped 1 more rich my needle but i have 2 other groove.I w'll try one more rich

And what means (((varnished up)))? Thank you

P.s There is a way to put the jet needle in the hole.The Needle are in a jet needle but there is a way to put that needle jet .??? Seems the 2 hole are the same?

 

"Varnished up" means gas that has jelled from sitting too long and coats bottom of carb bowl,jets,etc! Doesn't sound like this is your problem!
You can remove the top of the carburetor and remove the slide and rubber diaphram that has the jet "needle". The "needle jet" stays in the carburetor body. Remove "needle" from the slide by pushing up.It has a small "e-clip" that can be moved to different notches. If the clip is set on the "2nd position", just move clip one position lower and see if runs better,if NOT,then you can move lower and check how it runs(this causes a "richer" condition. If it runs worse,then move the clip up to "lean" the low/mid range. You may have to experiment with different positions to get it right! Hope this helps. OPT

 

Old Polaris Tec. I have a question for you maybe you can help. I started a new tread "radiator help" I didnt want to ask here because I didnt want to hijack.

 

I believe I just answered it. OPT

 

Thank you so much for your support i made a mistake.A put the jet needle or the neddle jet the wrong side. This little cylinder wrong side loll.Thank you