Need Help. My 1988 Springer Softail has had a problem over the last 5 years or so, always the same thing. It runs like its only hitting on one Evo cylinder sometimes, but all of a sudden it will start running fine. I have had it in the shop a couple times only to have them work on carb but problem still happens. I even put a new S/S on it to see if that helped but ran good for a while and then back to same thing. One day it might run fine but I will get few miles down the road and it starts spitting and coffin and running shitty but all of a sudden it clears right up. I just put a new battery, changed fuel, changed all fuel lines and it starts right up now and sounds good but when you take it for a ride it kinda feels like a plug is fouled. That is my next step to change plugs. Any ideas? I don’t chance even ridding it for the last few years?
If something seems to be running on 1 cylinder, you usually look into the ignition, or something electrical. Determine what you have for an ignition coil. Test the coil for ohms resistance. You can usually find the specs (for most coils) on line, or in forums. Check your plug wires. Make sure they are not corroded or cut. Make sure they are secure. Determine what you have for an ignition (pick up). Visually inspect it. See if you can find a test procedure for it. Test your charging system. Trace your ignition wires. Make sure that they are all secure and that none are creating a dead short. Inspect your ignition switch and breakers. Make nothing is touching ground in those areas.Related Videos:
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My 1990 Harley Davidson FLHS starts on one cylinder, Then catches up and runs on both Cylinders until it gets hot then it drops down to one again
I have an 87 evo FXSTC, on my last ride with a buddy, about 10 miles out my bike began to misfire, sputter, die out while riding, but then it would come back to life while moving. Also, when I throttle down and then up there would be a delayed response and all of a sudden it would lunge forward, making it difficult to control the bike. We stopped and changed out plugs with no results. As I limped back home it got progressively worse, to the point that it would stall each time I stopped which required to restart the bike. At one point, it ran normal again but only for about a mile or two. I've checked the voes and it checks out, though it closes on #2 of the vacuum gauge instead of 3 to 5 as to what I've read and heard. I've not checked the coil as of yet but will before I change anything out. Any advice I can get would be greatly appreciated.
My 2004 Sportster 1200C runs great for the first seven miles, then it sputters and misfires but does not stall or die. Spark plug # 2 always getting fouled-up. This sporty only has 500 miles on it. Please help.
I had the same problem with my 82 FXR. I had it in the shop several times and they couldn't find anything wrong. It turned out to be a coil wire that was hanging down on one of the cylinder fins. It had burnt/rubbed through and was shorting out on the fin. This only happened at uncertain times because it had to vibrate over to the fin. Who knew? Even Harley was amazed because it looked perfectly normal otherwise.
Different question sorry. I've a 2004 Softail FXSTI I just replaced my speed sensor but my speedometer is still moving til it max's out. Please do you have any thought on this I tried to bring up a code all I got was dIA9 I think. that's what showed
I have a 1990 FLHTC. It would run on one cylinder and then seem ok. checked the intake manifold for leaks, discovered the studs were pulled out of the bottom end. Fixed the studs with Time serts , works now.
My 86 FXR had similar problem finally discovered intake gasket in head had disfigured causing it to suck air.
mine was just a fuel filter that couldnt keep up with the flow it ran good for a few miles then spit sputered then came back to life couldnt figure it out for a while
Always simply check your battery connections at both ends of the wires. Make sure the cable ends are clean of any corrosion and "tight as a fish's arse!"
One carb feeds two cylinders. One cylinder not firing will NEVER be the carburetors problem. For combustion, air, fuel and ignition or ignitor/ fire-spark. Air and fuel are delivered simultaneously from one source, equally to both cylinders. Spark is individually sent to each cylinder in a timed manner. The problem is in the ignition system.