Ok so hopefully somebody can get me in the right direction. This problem been ongoing for about a couple months or so. First let me say it's not the carb or a fuel issue as I have rebuilt the carb and checked the tank to make sure I am getting gas. No problem there. Anyway I was riding one night when all of a sudden the bike started sputtering like I was running out of gas. I would lose power and then all of a sudden it would catch and take off like a bat out of hell because I had it throttled up to keep me going. It has been doing this once in a while for a couple months or so now. Thing is it will run great at times. Hell, been a couple weeks up until last saturday with no problems. Then last saturday I rode for two hours and on the way home same thing. Started losing power and died on my. Then I would start it up again ride for 3 blocks no problem until it did it again. Did that the whole way until about the last 5 minutes it ran fine with no problems. I am thinking it is a short somewhere or the ignition but wanted to get some input see if anyone got some ideas. My old coil was cracked so I replaced it with a brand new coil so that should rule that one out as well. Also as stated I rebuilt the carb and cleaned out all the jets so prob isn't there either. Thanks in advance for any help.

 

My wife's '89 Custom Softail had the exact same symptoms a while back and I replaced several things. Ignition switch, coil, plugs, etc. Turned out to be the ignition module under the seat. Replaced that and no more problem. I'm betting that's your trouble. Just curious, does your bike have the rubber compliance fittings that connect the carb to the engine? If one of those has a hole or crack in it, the bike will run rough, but usually at low rpms.

 

I would start by cleaning all engine grounds and connections. Pull the main negative and shine up the ends.

 

Cleaning contacts can only help. I work with an old telephone guy, and he says if you are trouble shooting, and you find a problem that seems unrelated, fix it... He has a long funny story that follows, but its true. Bad connections can wreak havoc of intermittent issues... I had the same sounding problem and cleaning all the grounds and contacts seemed to solve my issue. Worse case scenario is moving forward you can rule that out .. just my pennies

 

Does it have an in-line fuel filter?

 

Something stupid but maybe next time it's acting up take the gas cap off and see if it clears up. I've had similar issues due to a cap not venting properly.

 

Tug on the wire under the cone while it's running. Rubber mount motors break the wire going to the ignition sensor, giving intermittent problems until it stops permanently.

 

Mine did the exact same thing for a while, ended up the battery had an internal short, she would fire up and once got going it acted like it dropped a cylinder, then ran fine for days, and finally left me on the side of the road the last time it did it. These systems arent like cars as u can take the battery out of a car and it will continue to run. Harleys need a battery to even run to complete its loop, disconnect ur barrey while ur bike is running and u will see it will die. If u got a bad cell or internal short, it wont complete the circuit and it will act as u discribed.

 

Hi everyone I'm having a similar problem with my 92 FXR. Everything will be running/working like it should then all of a sudden I will lose power all my lights will dim and gas gauge will drop. The bike will want to stall; as soon as I twist the throttle the bike will come back to life only to lose power again. It's been happening on and off for the past 6months and I can not track it down. I'm losing my mind trying to figure it out.
I've replaced the ignition module (happend before and after I replaced it) I've checked almost every wire on the bike. I've replaced the ignition switch. I've replaced motor to frame ground. I'm pretty much at a loss for other things to check. I feel it's not a fuel issue due to the fact my lights dim and gauges drop. Any help would be much appreciated!

 

Check charging system. Check plug at stator.