I have a 93 Soft tail Heritage with some power issue while riding. I started with the simple stuff like replacing the coil, plugs and wires.
So here is how it all started. As Im riding the bike after a few miles and the bike become hot, it starts to putter and the bike loses power. Now imagine doing 80 MPH and all of the sudden the bike drops in power. Not a fun place to be in. After puttering all the way and at times the bike will kick in and out I finally made it home. Took it to the shop and my mech said that the gas need to be re-sealed. Ok sure no problem. 700 hundreds and 45 days later the bike is ready. I take her out for a spin and she was running like old time. But wait! A few weeks later she started again. WTF! I aint spending another 700 hundred dollars so I said let me see what I can do. Keep in mind I am no mechanic. After asking around and getting others opinion I started with the basic.
I few months ago my stator went out. The reason I mentioning this is because the symptoms were the same. Loss of power and sputtering until she died. It loses power and sputters off and on but doesn't die. I also had a issue a few years ago when I was riding it was doing the exact same thing. And for the life of me I couldn't figure it out. After playing with it I found the problem. One of the coil wires was broken and barely touching. Hence the puttering and stuttering.
Cool I fixed the wire and off I went. Im mentioning all this because the symptoms are exactly the same. It has to be electrical. So replace the coli, wires and plugs with high performance pieces. She ran great. Took per for a spin and I was on cloud 9 that she was running perfect.
A few days later I took her out for another spin and she was running great. Until it happen again. Made a right turn to take some back roads to cruise around barely breaking 35 MPH she sputtered, puttered again. WTF?!? As I gave her more throttle she would pick and then putter, pick up again then puttered. Until she ran smoothly again for a few miles. I pulled over and left her running while checking the connections to make sure nothing was loose or disconnected. All look good. Started riding again and she was acting pretty good. But I need to air her out to see if it would act up again. Kept going down the road and an opportunity rose when a light turned yellow and I aired her out and she did great. So now Im thinking WTF is going on here. I did it a few times without having any issues. So I headed straight home after riding 50 miles. As I turn on a small highway I figured let me aired it out again one more time. ****! she did it again. At this time I sooooo pissed I just wanted to run her into the pond. I went home had a cold one and just mellowed out. My neighbor keeps telling me its a gas pressure valve. Not all bike have pressure valves and my bike does not have one. I followed all the lines from the carb to its destination. Choke, overflow and gas line from the peacock. Im sure its electrical because I ran out of gas before and it sounds or feel nothing like. I sprayed some WD40 on where the carb connects to the manifold and all good, no leaks.

Anyone please. Im not gonna take her back to the shop to waste my time and money. I have notices lots of forums with bikers with literally the same or close to the problem I am have. HELP!!!

 

 

How are those circuit breakers treatin' ya?

 

i had similar symptoms a few years back. Turned out I had a sharp turn in my fuel line and it would cause an air lock situation. it happened and went away, happened and went away. thought it was electrail to. simple adjustment of the petcock postion, straightened out the gas line, all fixed, never happened again. Maybe you will get lucky

 

 

Thanks for the response. When I originally sent the bike to the shop my mechanic diagnosed the bike with paint in the tank. After they fix the tank the bike ran good. I’m thinking that another issue arose. As I mentioned I replaced the coil, plugs and wires. She ran really good afterwards. I took her out the next day and In the middle of the ride she started acting up again. I’m gonna replaces the the fuel line from the peacock to the car and see what that will do. I also sprayed WD40 in the carb to check for leaks and all seem good. I checked the ignition switch and all seem good but hard to tell.

 

I'd work on isolating the problem. Using jumper leads and some masking tape, I'd fasten a voltmeter to the center console and check some circuits dynamically. First, making sure that the ignition coil is receiving voltage when the symptoms occur. If you are, you've just eliminated the ignition switch, the master fuse and all the wiring in between. If you are dropping voltage, you can work upstream from there. I wouldn't just toss parts at this.

 

 

Given the intermittent nature of your problem and that when it's not acting up it runs great, I'd lean more towards electrical. Generally, with an issue with the carb, such as a needle and seat issue in the float bowl or crud in the tank, you'd have to clean something out to eliminate the symptom. One potential clue would be to check the voltage drop on the circuit. You could have 12.5 volts at the battery and only 11 to 11.5 at the coil. The proper way to do a voltage drop test would be to hook the positive lead up to the battery and the negative lead to the power supply terminal on the coil. If you've got more than .5 volts registering, that indicates resistance in that circuit. Resistance and heat go hand in hand and both will increase the longer it's operating and the voltage drop would increase.