Hi everybody,
I'm having the notorious high idle problem. and I need some help getting the concepts right. please let me know if my understanding is ok here.
after reading extensively through a high idle search I still can't wrap the old brain around the air mix screw can someone please help me clarify?
screw in = higher rpm's
screw out = lower???
is this right.
I'm confused because I thought more air = higher rpms but turning the air mix screw out gives more air right?
the bike idles at 4500 when its warm and in nutral. I've ruled out choke cable, it slides well. I've ruled out tight throttle, if anything its loose, there is a lot of play.
I'm left with lean mix. so its either the carb boots to the cylinder didn't get a good seal when I put the carbs back on, or its the vacume hose, or its the air mix screw.... basically I feel like air is getting in there at some point right? wouldn't that mean screwing in the air mix screw for less air?
I'd like not to have to reseat the carbs if I can help it but that seems the most likely point of entry for bad air. next time the bike is warm i will see if I can get the idle down by turning the air mix screw.
and by the way through all this there is no response to the idle screw I can turn it either way all day long till its flush or falls out and get no change. this makes me afraid my valves are bad. could that be?
thanks for the help.
d
You need to re-jet. Look in the FAQ's for more than you ever wanted to know. RE-jetting will some the problem nicely.
ChuckS
sorry I forgot to mention, the bike was rejetted by the previous owner, I should have written the numbers down while I was in there cleaning but didn't.
should I still rejet?
After the usual - try airbox boots being loose or holes in the air filter. Bitten by that one.
Cool.
Srinath.
cool. I'll check that. i had a hard time getting the seals right on front and back of carbs when I put them back on so air could be getting in on either side? the filter is pretty new, I just oiled it so I don't think there are holes. what about the guys who say to get rid of the air box all together?. wouldn't that f up the idle? on top of other various dirty air problems?
No, getting rid of the airbox means you put either a lunchbox (big-ass square filter for both carbs), or individual pods on each carb's inlet.
Running no filter on the street is probably about the same level of stupidity as not wearing a helmet.
Same level of stupidity?
Yes.
Same level of consequences?
No.
I'll take a fried engine over a cracked head any day of the week.
thanks for the clarification, when I read about no airbox in some posts it confused the hell out of me. I thought that sounded like a bad idea.