Stuttering with the Turn Signal on?

delagem

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As the title says; any ideas what could cause this? Ignition sputters exactly in time with the light on; either side causes this. Runs fine briefly when the light is off. Runs fine when the signal is cancelled...

I checked the wiring, and did find a chafed spot on the turn signal wire, and the adjacent ignition wire coming from the fuse box. Easy, I thought! But liquid electrical tape, and wrapping the harness back up in electrical tape didn't change anything.
 
Check the voltage at the + side of the coil(s) with the turn signals off and then see if it holds steady when the turn signals are lit. Would also help to know more about your bike. Year,mods.
 
If your bike is using the original indicator unit, it draws quite a lot of current initially, if your battery is not up to snuff or you have a poor voltage on the brown wire, this could cause the coil voltage to drop enough to stop the engine.
Ignition switch is a noted area for voltage drop, also the kill switch. Hope it helps.
 
Thank you for the suggestions. I'll check it out. I can toss another battery in to test, but the current battery starts the bike just fine.

Bike is pretty much stock, as listed in the signature. No real mods to speak of, except cafe bars and seat.

Bike is a bit of a pig to start. Sputters and stalls probably a dozen times before finally agreeing to run at idle only. Rolling on the throttle brings more sputtering and misfires, for maybe 2 min's till it warms up and will take throttle. Choke doesn't help. Probably a separate issue with the carbs causing this I suspect.
 
Unplug your voltage regulator and see how it does. I know that may sound like a crazy test. Your bike has TCI ignition. Do a search on TCI rare earth magnet.
 
My bike does similar, I'm getting ready to do the LED tail light.
 
Get a voltmeter and check the alternator output, idling and as you rev to 3000 RPM
 
Check the fuses and fuse holders in the fuse box, the metal has often rotted, then they no longer grip the fuses well.

Thank you Gary, I wire brushed the fuse holders, Scotchbrite'd the fuses, and reassembled with dielectric grease

Unplug your voltage regulator and see how it does. I know that may sound like a crazy test. Your bike has TCI ignition. Do a search on TCI rare earth magnet.

Ah, great idea! Not crazy, I remember reading about that test.

My bike does similar, I'm getting ready to do the LED tail light.

Interesting. One of the few mods the bike has, is a Dime City Cycles Norton replica tail light. Probably not relevant.

Get a voltmeter and check the alternator output, idling and as you rev to 3000 RPM

Will do, thank you.

Michael
 
When your turns flash they draw around 57 watts, or a bit over 4 amps. The headlight is only 50 watts, 3.5 amps on high beam. That's if everything is as it should be. Any poor connections will draw more.
I might suggest going through your turn wiring and clean and tighten every connection. Same with the ignition wiring.
Some of us recommend starting at one end of bike and working to the other end, cleaning and tightening every connection before even trying to start the bike. A bit of dielectric grease on every connection will help keep the connections working better.
Doing this to before going to far in a bike will help fix and prevent a lot of electrical issues before they become issues.
Where any wires black wires, grounds, hook to the frame or engine you want clean bare metal to bare clean metal. Paint, rust, dirt, powder coat, all thus things make for poor connections.
Leo
 
Unplug your voltage regulator and see how it does. I know that may sound like a crazy test. Your bike has TCI ignition. Do a search on TCI rare earth magnet.

GLJ nailed it! Thank you sir!

Bringing this back to the top, with a resolution. After many conversations and reading, I fitted one of Jim's OEM alternator rotor rewinds (thank you Jim!) in place of the MikesXS rotor that the PO had fitted. This not only solved the prior running issue where the bike needed to warm up for 5 minutes before it would take any throttle without popping and refusing to rev above 2,000 to 2,500 rpms, it also solved the stuttering whenever the turn signal was on.

Jim's theory, I believe, is that there isn't much metal in the outer face of the aftermarket rotor. This metal acts as a shield, preventing the electromagnet field from interfering with the ignition pickup magnet. Once the bike ran for a few minutes, the battery demand for amps would go down, and the magnetic field would subside, ending the interference, and the bike would run properly. Turning on the turn signals would bring the demand up, increasing the interference and the stuttering would start.

Thank you everyone who I spoke with, PM'ed, bounced ideas off of, and offered help in these threads!

Michael
 
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