Trying to figure out what the problem is. First some backround I'm not a Harley mechanic I work on Japanese bikes. So not new to bikes or mechanics. Anyway customer brought this bike to me an was leaking fuel from the accelerator pump diaphragm. Also the pump was not shooting fuel down the throat. Figured it shouldn't be very hard to fix. Got new parts including bowl gasket and needle valve because it was also overflowing the carb while sitting. Anyway, pulled the carb and did a complete cleaning, every jet every passage is clean and clear. reassembled and installed on the bike, fires instantly, idles great. But as soon as I give it some throttle it dies out, like it's starving for fuel. Accelerator pump is shooting out fuel if the throttle is cracked fast. but not opened slowly. Only way to even try to ride it is to pull the choke/fuel enricher so it's getting enough fuel. tried checking for air leaks but have not found any as of yet. none at the carb, none at the intakes. So what am I missing here. After doing research it seem these bikes are known for this exact problem yet everyone points to air leaks and I cant find any. Owner said it ran fine before. Just leaked fuel. Do these carbs not like to be clean? Ha ha...

 

Are you sure during the cleaning that the needle jet didn't get lost or reinstalled upside down? The needle jet is held in place by the needle jet holder (emulsion tube) which is what the main jet screws into. The big end of the needle jet should be sticking up through the bottom of the carb throat.

 

Thanks for the info. I will double check to make sure that the needle jet is in the correct way. I may have gotten it in upside down.

 

Have you also checked, with the A/C off, to make sure the slide moves up and down properly when you rev the motor?

 

I don't know what you mean by A/C but yes the slide moves up and down correctly. Great call on the needle jet, I did have it in upside down. Bike now revs like it should. Idles great, took it for a test ride and runs ok, but seems to be stumbling a bit. Have the idle mix screw at 2 1/4 turns out. Maybe to rich? As far as I can tell the bike is stock.

 

Good deal, it's easy to do.
Can't help much on the mix screw as a lot depends on what size jets are installed, but up to 3 turns out is ok. If it takes more than 3 turns out, it's time to go up one size on the pilot jet.

A/C = Air Cleaner

 

A/C = air cleaner, got it... Well I don't remember what size jet it has in it right now. Assuming whatever is stock. I'm going to try it at 1 1/2 turns out. and see how it runs. Pulled the plugs and looks very rich black and sooty, cleaned them. I did write down when I took apart and the idle mixture screw was at 1 turns out.