My bike is running too lean i am stumped.. I have a 175 main jett in my left carb and a 180 in my right carb. i have the needle jett set to the 4th position... my air to fule mixture screw is 2.5 turns out in the left carb and 3 turns out in the right carb... what should i do to richen up the bike, mabey move the needle jett to the fifth position?? ( its a stock needle)

 

What makes you think it's too lean? Is it backfiring or did you do a plug test? Is this over the whole throttle travel or just in the mid travel? Changing the needle position will only change mixture (primarily) between 1/4 and 3/4 throttle. Below 1/4 is the pilot jet and screw, above 3/4 is the main jet.

What aftermarket parts are you running, if any, and what changes did you make in the jetting since?

 

ok, i noticed that my header pipes turned blue , (I know that when they turn blue it not jetted right) So i pulled the plug and sure enofugh the porcilin was brite white. i put 3 hours of ride time on the bike after new spark plug... I am running a stage IV trinity exaust system, with an open air box prodesign air filter... and i just put a new clutch in the bike, but that should have nothing to do with it... the power feels like its there, i dont really feel any bogg just alittle out of first. now come to think of it when i first jetted the bike it rode like a monster now it feels like it lost some power... harder to pull it off the ground as to couldnt keep it down up to third gear... ??? make any sense?

 

How long it been since you adjusted your valves? Intakes could be tightening up. Only reason I suggest this is your statement that it has lost power over time.

 

you know something Your right.. i just bought the bike from somebody, the bike was completely stock i dont think the kid did any maitnance to the bike besides an oil change regullary.... but you think that would make the bike lean?? before i did the mods to the bike i pulled the plug and it was just right like a meduim tan not to light not to dark.....?? what you think??

 

I'd rather refer to someone else's expertise on this, but if the intakes are tight, you will be drawing a bit more air/fuel mixture in, so the jets may be acting a bit lean. (kinda like adding a longer duration cam).

Anybody else wanna throw thier 2 cents in?

 

well i just recently jetted mine first time i've done em i just followed the directions but how do you tell if its running lean or rich?

 

well he could try to run a smaller jet to let less air in. then if that doesnt work then he could turn his air fule mixture screw (but with the same jets [stock] or whatever he had in there to begin with) then change his fule mixture screw i dont know off hand what the way is to increase the fuel is but try to do that. and if your plugs were light brown not to dark and not to light that means that it was running perfect.

 

and if your losing power also check your airfilter maybe

 

<div class="FTQUOTE"><begin quote>Originally posted by: TacticZero

well i just recently jetted mine first time i've done em i just followed the directions but how do you tell if its running lean or rich?</end quote></div>

you can tell if its running lean or rich by the plug
dark=rich to much fuel
light=lean to much air
and also by how you use the power/throttle it will backfire if its to lean and will barley run if its to rich