I have a 2003 Fatboy (carb). When I'm coming to a stop sometimes it will sputter like it's going to stall out until I give it gas to keep it running. This is annoying and a bit embarassing. It seems to idle fine but sometimes this will also happen right after I've warmed the bike for awhile and go to take off. I've only had the bike a short time and was told it has a jet kit in it but that's all I know. The bike has about 19,000 miles on it. If it's the carb I've never worked on a carb before and would rather just by a new one and install it myself then pay the dealer to work on my old one if it's something I can't do myself. Any advice is greatly appreciated. Also I've heard of guys switching to Mikuni 42 carbs what's your guys take on them?

 

need to know what carb you have and what jets were installed? do you have a Fuel management devise on it --- Fuel-Pak , TFI , etc.

 

First step, check the plugs to see if it is running too rich. If the plugs are black and sooty you are too rich. You are looking for a tan appearance. You can lean it out with the mixture screw under the carb. All this is supposing the jet was near right to begin with and the choke is not sticking. Anyway, new plugs are always a good place to start and they are cheap. Oil fouled plugs are also suspect.

 

Hi if you have a stock carb that is a lot of the problem.Get a good carb S&S wake it up.It probably needs to be cleaned .And like the other guy said it might be the plugs.

 

Plus 1 on the plugs... I would start there also. The Mikuni 42mm will make a huge difference best bang for you buck if you ask me. It's a night and day difference compared to the stock carb and with the Mikuni EZ kit you won't have to change you cables, but will will have to reroute them to come at the carb from a different angle. You will have to grind the fins on the cyl heads just the last one on each head for clearance for the carb... not hard at all. Best $300 I ever spent... well a side from the ladies... lol

 

My experience is cheap or poor quality gas.
Try a 93 octane by a name brand, ie Exxon or BP/Amoco

 

I bought the bike in August and after experiencing the issues with it wanting to stall the first thing I did was put on new plugs and wires. The carb is stock and I don't know what jets are in it. I live in NY and have put the bike away for the winter and I just want to get an idea of what could be causing this as I don't wish to deal with this again next year.

 

Also I always run 93 in the bike.

 

And the old plugs looked good when I swapped them out.

 

The Keihin CV carb is one of the best carbs Harley has ever put on their bikes. S&S and Mikuni are both good carbs, but you can "tune" the stock carb for very little cost and have a great performing carb. Google "Keihin CV carb" and click on www.nightrider.com/biketech/hd_cv_mods.htm or use this link. It walks you through the modifications and tuning for your carb.