Misfiring

[Phare Est]

For voltage being equal to initial batt.voltage at other critical locations, first turn key on THEN check batt. voltage. Next, unplug a coils primary leads, turn key back on and check voltage at that coil lead wire. Needs to be the same as voltage at battery was. If it's lower, I first would suspect internal contacts of STOP/RUN switch are cruddy and loosing full contact. That switch has to be removed, taken apart and cleaned. The whole internal contact assembly has to be clean. 'Looks clean' doesn't cut it. The STOP/RUN switch completes the electrical running circuit.

Thanks motoman! I'll run the test on the battery and the coil lead wires. If it does turn out to be an ignition switch problem, I may just go ahead a buy a new one (https://fortnine.ca/en/emgo-ignition-switch-40-71340). I did wash the bike after taking out of storage, which is when the misfiring, sputtering and NEUTRAL light problems started...

[skids]

Sorry about replying to my own post, but I think I need to elaborate on it a bit. Someone described the condition as a stray current when the neutral light is not shining. At that time, the current is “searching for ground” and interferes with the ignition circuit that is in the same loom.

[Ranger_xs1100]

fuse box?

Are your turn signals working ok?
When my green neutral light was giving me problems on my 81 LH, it turned out to be the 20 amp fuse holder, (not the fuse itself). However the turn signals and brake lights were not working right either. Replacing the fuse holder solved all of those problems. It's possible that when you were fiddling with the alternator wires, you were inadvertently jiggling the wires to the fuse box as well.

[DiverRay]

When my green neutral light was giving me problems on my 81 LH, it turned out to be the 20 amp fuse holder, (not the fuse itself). However the turn signals and brake lights were not working right either. Replacing the fuse holder solved all of those problems. It's possible that when you were fiddling with the alternator wires, you were inadvertently jiggling the wires to the fuse box as well.

If you still have the factory fuse box, REPLACE IT! The glass fuse holders use spring tension to make good contact. ANY spring looses tension after 30+ years. You can get a five position blade type holder, and that should be fairly easy to install. And as poster earlier, replace the main fuse holder with a blade type as well.

[motoman]

Phare Est, ignition switch voltage has nothing to do with what I stated for you to test....one thing at a time to resolve issue. Again, batt. voltage with key on, as opposed to coil twelve volt wire voltage with key on. If voltage at coil wire is lower than voltage at batt., then your missing the necessary voltage needed for coils to operate properly. A +1 on Diver Ray's suggestion, as that IS also a common location for voltage drops.

[Phare Est]

Are your turn signals working ok?
When my green neutral light was giving me problems on my 81 LH, it turned out to be the 20 amp fuse holder, (not the fuse itself). However the turn signals and brake lights were not working right either. Replacing the fuse holder solved all of those problems. It's possible that when you were fiddling with the alternator wires, you were inadvertently jiggling the wires to the fuse box as well.

If you still have the factory fuse box, REPLACE IT! The glass fuse holders use spring tension to make good contact. ANY spring looses tension after 30+ years. You can get a five position blade type holder, and that should be fairly easy to install. And as poster earlier, replace the main fuse holder with a blade type as well.

Hi Ranger_XS1100 and DiverRay,

The turn signals, headlight and brake lights work fine. I replaced the factory fuse box with a new blade fuse box last year. The 30 amp main fuse was also swapped with a blade fuse. Everything was working perfectly before I put the bike in storage. I went ahead and changed all the fuses after I noticed the misfiring and sputtering, but the problems persisted.

I will have time to work on the bike in a couple of days. Thanks to everyone for the advice!

[DiverRay]

OK, then go to the ground...wires. Pull all ground wires and clean, put anti-seize on, and re-connect the screws/bolts.
Next, behind the metal plate holding the fuse block is a six position connection for the Alt. check this connector for heat damage, warped plastic, or even burned plastic. If you see ANY problems replace both connectors. I like buying from here:http://www.oregonmotorcycleparts.com/connectors.html, but noticed he is out of stock on the six-pin connectors at the moment. Tony is an xs11 member who makes electrical parts for a LOT of old bikes.

[Phare Est]

OK, then go to the ground...wires. Pull all ground wires and clean, put anti-seize on, and re-connect the screws/bolts.
Next, behind the metal plate holding the fuse block is a six position connection for the Alt. check this connector for heat damage, warped plastic, or even burned plastic. If you see ANY problems replace both connectors. I like buying from here:http://www.oregonmotorcycleparts.com/connectors.html, but noticed he is out of stock on the six-pin connectors at the moment. Tony is an xs11 member who makes electrical parts for a LOT of old bikes.

I checked and cleaned carefully all the ground wires, except the main ground wire underneath the air box, since one of the screws (the one closest to the battery seat) is impossible to crack loose... Any advice?

As for the alternator plug-in behind the fuse box, it was changed last year, along with the three white wires going to the REG/REC and the tach. I used 14 gauge wire.

I'll be heading on a business trip on Friday, so I may not be able to work on the bike until Wednesday or Thursday of next week. On another topic, I am the happy owner of a 2007 Kawasaki VN2000 (base model) since yesterday, so my XS11 will be competing for attention from now on. We'll see how that works out 😁.

[DiverRay]

I ended up putting another ground from battery to engine on my '79. Seemed to cure the odd problems I was having with it. I used #8 wire, as I had it and connectors available.

[Phare Est]

I ended up putting another ground from battery to engine on my '79. Seemed to cure the odd problems I was having with it. I used #8 wire, as I had it and connectors available.

Hi DiverRay,

Thanks for the tip! That's exactly what I'll do.

[Phare Est]

I used an 8 gauge wire to connect the engine to the negative battery terminal. The problem persists, but there was certainly no harm in adding that wire.

I'll be replacing the ignition switch. if that doesn't resolve the issue, then I suppose it's back to square one.

[bikerphil]

Have you thoroughly checked the condition of the P/U coil harness, especially in the area where it runs near the exhaust? Those alternator wires you were messing with run under there too. Could be a broken wire there.

[Bonz]

I went back and re-read the full thread. Post #4 says you replaced the float bowl gaskets. Did you double check they were not impeding the float movement inside of the bowl? It is a known issue for some float bowl gasket’s to overlap into the bowl and need trimmed, otherwise the float hangs up.

[Phare Est]

Have you thoroughly checked the condition of the P/U coil harness, especially in the area where it runs near the exhaust? Those alternator wires you were messing with run under there too. Could be a broken wire there.

Hi bikerphil,

I haven't had much time to work on the bike lately. I did replace the stator, but I suppose there could be a field coil wire issue. As Bonz suggested, I will have a look at those new float bowl gaskets if my new ignition switch doesn't solve the misfiring problem. I'll be on the road again this week, so I will only be able install the switch next week.

[bikerphil]

Not the field coil wires but pickup coil wire harness that runs under the rear of engine.