Oil useage and Overheating -Airscrew?

niftyfifty · Post by **niftyfifty** » Mon Apr 24, 2006 10:20 pm

with the idle screw and air screw are they there simply to set your idle speed right or do they have an impact on the fuel/oil/air ratio?

i mean by setting it to one extreme will you foul spark plugs and to the other extreme overheat and melt pistions?

The reason i ask is because i have two carbs, the original on the bike has the air screw so loose its on its last threads, this bike idles perfect. the other carb has been set to service standards and it also idles fine.

am i running the risk of melting pistons or fouling plugs by using the original carb that the bike came with?

MySpree · Post by **MySpree** » Tue Apr 25, 2006 8:24 am

mines on there about 2 1/2 screws out

DENMANSHAFFER · Post by **DENMANSHAFFER** » Tue Apr 25, 2006 4:25 pm

VIRTUALLY ALL MOTORCYCLE/SCOOTER CARBS HAVE A SEPARATE CIRCUIT / JETS FOR THE IDLE SYSTEM AND THE RUNNING SYSTEM.

THE IDLE CIRCUIT ONLY CONTROLS THE MIXTURE UP TO ABOUT 1/4 THROTTLE. THE AUTO BYSTARTER (AUTO CHOKE) IS ALSO ACTIVE TO ASSURE A RICH MIXTURE.

AFTER 1/4 THROTTLE, THE FUEL QUANTITY IS CONTROLLED BY THE NEEDLE JET'S DEPTH INTO THE MAIN JET CIRCUIT.

AT WOT, THE FUEL QUANTITY IS CONTROLLED STRICTLY BY THE SIZE OF THE MAIN JET.
MAKE SURE YOU HAVE ADEQUATE AIR FLOW FROM FILTER THRU THE CARB. IF YOUR AUTOBYSTARTER STAYS ENGAGED, YOU MIGHT BE SUFFERING FROM LACK OF AIR.

niftyfifty · Post by **niftyfifty** » Tue Apr 25, 2006 8:10 pm

if im understanding that right, if its idling right at ethier of the extremes of the air screw then thats fine?

Farfignugin · Post by **Farfignugin** » Tue Apr 25, 2006 8:25 pm

if ur mixture screws are set correctly (by "correctly" i mean the following: Idle at approximately 800rpm; air/fuel mixture set properly for highest idle at current barometric pressure, temp., humidity, etc...) your scoot should accelerate at a very high rate (idle to full speed in maybe half a sec.). The carbs on the sprees are VERY TOUCHY to changes in the atmosperics, I've had mine set perfectly for an early afternoon ride, but as sun starts to set and it get slightly cooler it starts to run slopily (if thats a word). All in all, to get the best performance out of ur scoot, tune the carb before every ride. I know this can get annoying, but hey... what do you expect from a carburator?

niftyfifty · Post by **niftyfifty** » Tue Apr 25, 2006 11:50 pm

in the manual it says:

attach tachometer and set throttle stop screw to specified 1800rpm.
when engine misses or runs erractically proceed with:
*screw in air screw till lightly seated and turn out 1 3/8 turns
*reset idle speed with throttle screw
*turn the air screw in or out to find the highest idle speed.
*reset idle speed with throttle screw
*make sure engine doesnt miss or run erractically otherwise repeat steps

WHAT DOES RESET IDLE SPEED WITH THROTTLE SCREW MEAN??

Does it mean readjust till 1800prm or does it mean screw it right in?
I cleaned the carb and am having difficulty with these adjustments, also there is now white smoke coming from the exhaust, if i use one carb. and blacker smoke if i use the other carb which is also just been cleaned.

what does the smoke mean?

MySpree · Post by **MySpree** » Wed Apr 26, 2006 8:14 am

my aeros got a tac, and a voltimiter under the seat.

Farfignugin · Post by **Farfignugin** » Wed Apr 26, 2006 9:17 am

It means to get it back to 1800rpm