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Flabadabadingdong
04-17-2016, 3:10 PM
Trying to help my buddy get his '92 883 back on the road. The bike has a bit of a hard time starting but after it starts it idles fine. If you crack the throttle it stumbles and falls on its face but if you roll on the throttle easy, no problems. Changed the gas, plugs, wires, carb is clean (super e), and readjusted it but the problems persists. Bad coil? How can I trouble shoot it to see if thats the culprit?

BadMonkeyMW
04-17-2016, 4:08 PM
What you're describing sounds carb related. A Super E on an 883 is really too big of a carb. You can make them run alright, but a CV would be much better. Having said that, it sounds like you may have an issue with your accelerator pump adjustment. That stumbling/falling on it's face when you crack the throttle could either be too much of a squirt from the pump, or not enough. When adjusted properly and with the engine at full operating temp, you should be able to whack the throttle wide open and the engine shouldn't stumble. If it does, add or take away accel. pump fuel in 1/4 turn increments until you get the proper throttle response. Turn the pump screw clockwise the reduce the fuel it squirts in, and counterclockwise to give it more. Try that and see how it does. Good luck.

Also, what size idle jet is he running? Improper sizing there could explain the hard starting, but it could also be an intake leak.

Flabadabadingdong
04-18-2016, 1:38 PM
What you're describing sounds carb related. A Super E on an 883 is really too big of a carb. You can make them run alright, but a CV would be much better. Having said that, it sounds like you may have an issue with your accelerator pump adjustment. That stumbling/falling on it's face when you crack the throttle could either be too much of a squirt from the pump, or not enough. When adjusted properly and with the engine at full operating temp, you should be able to whack the throttle wide open and the engine shouldn't stumble. If it does, add or take away accel. pump fuel in 1/4 turn increments until you get the proper throttle response. Turn the pump screw clockwise the reduce the fuel it squirts in, and counterclockwise to give it more. Try that and see how it does. Good luck.

Also, what size idle jet is he running? Improper sizing there could explain the hard starting, but it could also be an intake leak.

I forgot to add that the bike was running and riding fine with its current set up last year. I also adjusted the pump screw a quarter turn at a time from seated all the way out to two full turns with no success.

Tattooo
04-18-2016, 2:07 PM
I forgot to add that the bike was running and riding fine with its current set up last year. I also adjusted the pump screw a quarter turn at a time from seated all the way out to two full turns with no success.


Accelerator pump has dried out and gone bad..... Rebuild the carb......

84ironhead
04-18-2016, 2:33 PM
Or at least a accelerator pump kit.

BadMonkeyMW
04-18-2016, 5:39 PM
Accelerator pump has dried out and gone bad..... Rebuild the carb......

Agreed, and I would still investigate an intake leak.

Tattooo
04-18-2016, 7:53 PM
Or at least a accelerator pump kit.

Why would you not take the carb apart clean it and change the gaskets and O rings??

Sky
04-18-2016, 8:13 PM
Probably not the coil.
He said the carb was clean...
Is it pumping fuel? can you see the squirt?
Is the hole for the pump rod full of fuel? It should not be.
Did you lose the little blue o ring on the pump tower? When you dropped the bowl to check/clean it?
Or the ball(s) and/or almost invisible little spring "under" the pump cap?

What ignition are you running?
Stock; is the pickup in good shape? or is it melted.
Not stock: is there an advance weight assembly in the cone? Are they in good shape?

jdbuis
04-18-2016, 9:31 PM
Had the same problem on a 72 1000cc ironhead. Rebuilt the whole carb and tuned. Problem solved