After cleaning a carb:
Idle fuel/air mix screw set to factory 2.75 turns out from seated.
idle stop screw turned in till it STARTS to depress the end of the accelerator pump
Enricher (choke) engaged until the engine is warmed up.
at this point it should start and run without needing to touch the throttle.
Once warmed up and the enricher is off, the idle mix screw gets adjusted to 50rpm below saturation (saturation point is the magic spot where turning up the mix does nothing but turning down the mix drops RPM)
then adjust the idle stop screw to maintain 1400 rpm.
2009 Honda Rebel 250; 2009 Honda Shadow 750 Spirit "The bravest thing for me to do is admit when I am wrong" - unknown HRF Answer #1 You should take the MSF Rider Course HRF Answer #2 You need to clean your carburetor HRF Answer #3 Sorry we assumed if you didn't say otherwise
thank you guys!!! it's idling now but may need a good tune. the idle furl/air mixture screw has a tab and i read that you have to break off the tab to tune it right. i'm a little skeptical to do this. any suggestions?
if you noticed i replaced most of the screws to an allen head screws
The reason for the tab on the air/fuel mixture screw is so that the screw can't vibrate out or get too far out of adjustment. I've never had one move off of where it was set, let alone have it vibrate completely out. But others reportedly have. The initial setting should be done before the carb is completely assembled. If you aren't sure what the adjustment was before assembling, you don't want to remove the carb again, and don't want to break off the tab, there is a way to remove the tab. It is held onto the top of the screw with heat sensitive glue. Heat it up with a hair dryer on high or better yet a heat gun and pull it off. Then you can adjust the screw. If the glue is still on the tab/head, apply some heat and reseat it. If not, a dab of toe nail polish should hold it, or you can get a stick of top ferrule cement at a fishing supply store. The ferrule cement is heat sensitive.
The idle adjustment screw, as wjmrty described, has a black plastic knob on it. It is a totally different animal than the air/fuel screw.
Keepin' all the left over parts. Gonna use 'em to build another bike!
I never had a mixture screw move either flitecontrol, and never heard of one moving after it was set. I just assumed it was an EPA requirement to prevent us from adjusting it. Old carbs didn't have it, and newer carbs have been made even more restrictive and difficult to get to. Some carbs no longer have any adjustment, which seems really stupid.
1999 Honda Rebel CMX250C
2003 Harley Sportster 883 Hugger
1998 Harley FXDWG Dyna Wide Glide
ALL IN! GO TIGERS!