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Discussion Starter #1
So here is the biggest issue with my bike that is preventing me from trusting the bike past my immediate neighborhood.

NOTE: I am running a brand new MotoBatt AGM battery that is always fully charged, and on a tender when sitting for a while.

I put the key into the ignition switch, and set the bike to "ON" and the Neutral light comes on.

I flip the handlebar starter switch to "RUN" and the neutral light shuts off. No starter, no lights, no horn, etc. I checked my fuses for a short, and all of my fuses look perfect. If I cycle the key switch from off to on again, the Neutral light faintly comes on. It is almost as if the bike is acting like it barely has a charge.

Here is the interesting bit...

If I kick the bike over while it is "dead", the lights come on and it immediately starts to run. I found that if it is left idling, then as soon as I use a turn signal (for example), the engine cuts out. However, if I am revving the engine anything past idle, the bike can handle the electrical loads.

I hooked up a voltmeter to my battery to see if I am experiencing a sharp downturn in charge while using any of the switches, and to make sure that my charging system is actually charging the bike at 3-4k rpms. Nothing abnormal has been observed.

I took apart the headlight and opened up the "bird's nest" of wiring up there and verified that I have no loose wires.

I made a video documenting my findings from today which can help illustrate my issue.

 

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Sounds like a bad/intermittent connection on one of the battery cables. Could be at the battery or the solenoid or the frame.
 

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Discussion Starter #3
Sounds like a bad/intermittent connection on one of the battery cables. Could be at the battery or the solenoid or the frame.
Understood, I will reassess the connections at the battery and starter solenoid.
 

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Discussion Starter #4

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The neutral light goes out because one of the coils saps all the juice when you turn on the kill switch, turning the engine over opens the points and lets the neutral light come back on. With everything turned on use your voltmeter,grounded to the battery minus terminal, to probe the black wire in the headlight shell. There will probably be little or no voltage showing. Now move the lead to the black, then the red wire connection on the ignition switch. Finally move to the fuse box connector plug and check both sides of it. When you get to the place where the voltage jumps up you've isolated the problem spot. Finally check between battery minus and the green wire in the headlight to test your battery ground connection, the meter should not show voltage there.
 

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Discussion Starter #6
The neutral light goes out because one of the coils saps all the juice when you turn on the kill switch, turning the engine over opens the points and lets the neutral light come back on. With everything turned on use your voltmeter,grounded to the battery minus terminal, to probe the black wire in the headlight shell. There will probably be little or no voltage showing. Now move the lead to the black, then the red wire connection on the ignition switch. Finally move to the fuse box connector plug and check both sides of it. When you get to the place where the voltage jumps up you've isolated the problem spot. Finally check between battery minus and the green wire in the headlight to test your battery ground connection, the meter should not show voltage there.
Starting with the easy stuff, I disconnected the cables going to/from the solenoid and the starter, and the cables going to/from the battery and solenoid, as well as the grounding cable. I used an emery cloth to scrub the connections clean, and used QD electrical contacts cleaner to clean them up and reconnected the wiring. I later tried to recreate the issue where "everything goes out" but I was unable to, whether it was with electric start, kick start, lights off, and/or all lights + turn signals flashing. I ran out of time to go for a ride and run the system out a bit and try again, so I will have to wait till next week or so.
 

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Sounds to me like you got it now, electric start will present the biggest load and if that doesn't kill the connectivity, you're should be okay
 

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Discussion Starter #8
So I did not fix the issue. I went out for a nice quick ride around my immediate neighborhood today to get the engine to operating temperature to synch the carbs and set idle speed to spec. When I came back to the garage for tuning, the issue returned. I was quite pissed off, but anyway I went to get the multimeter to do the check ups that mike_in_idaho recommended. I had a mini alligator clip from the multimeter (connected to the battery negative terminal) detach and hit the engine crankcase and I heard a spark, and the neutral light came on! After a triple check, it looks like I had an issue of poor grounding?!?!?!

I detached the engine hanger bolt that also attaches to the ground terminal connection. It turns out that the engine hanger bracket was completely powdercoated on all sides and all holes and may have made for poor grounding? I used a rolled up piece of sandpaper to scrape away the paint and cleaned up any surface that may be related to grounding with electrical cleaner. The engine mounting bolt was cleaned up, and the ground connection was sanded down and covered in dielectric grease.

I reassembled everything and it looks like I have no recurrence of this issue. For kicks I tried to spark a clip from the battery (-) to the crankcase cover, and no spark was generated.

Thread closed, I hope!
 

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Yep, powdercoating has to go on both the mount plates and the spot on the frame where the contact is made... I guess I assumed you had done that :D glad it is NOW good to go!
 

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Discussion Starter #10
Yep, powdercoating has to go on both the mount plates and the spot on the frame where the contact is made... I guess I assumed you had done that :D glad it is NOW good to go!
You assume too much!

Yeah, now I just gotta sort out the wonky idle when the bike is at operating temperature...or just live with it :D
 

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Live with it long enough, along with some cleaner additive added, and it might just work itself out. Probably won't ever be perfect without truly cleaning them again, but it might work into something that runs well enough with a little fuel flow through it regularly for a while (ride!)
 
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