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Bike dies when turning handle bars to the right

6K views 24 replies 7 participants last post by  MSattler 
#1 · (Edited)
I had posted this originally in the engine forum, but it is electrical. The back story is that the bike would die whenever I turned the handlebars to the right. Several people suggested to check the left side wiring harnesses (makes complete sense, as it is adding strain there when turning left). I could not get the problem to duplicate yesterday, in the 95 degree heat, but I got it this morning when it was 70. Maybe the harness was more pliable yesterday in the heat. I have taken a video of the issue, and it has a relay like click when I get to the “dead zone”. Maybe kill switch? Maybe ignition? You’ll need audio for this, but it has a distinct relay sound coming from the right side of the bike. If the video doesn’t have sound for you, click the “v” in the lower left side of the video. It’ll take you to the page
https://vimeo.com/346534959

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#2 ·
Where is the relay for your coil mod? Is that it by the battery? Are the terminals fully insulated? No bare metal on the connections or pins?
 
#3 · (Edited)
That is it by the battery. Where you have the washers and the bolt. They are not fully insulated, just the female connectors attached to the pin. I caught a sheet metal screw in the front tire, and I was going to get a patch kit from O’Reillys. I can get some heat shrink there. It sounds identical to the relay that turns on when the ignition is turned on. So that would make sense, since the rear coil is the trigger. To test, I should be able to disconnect the trigger from the relay to see if that is it.
Update - I pulled off the trigger and sure enough, it stopped doing that. So... is it as simple as insulating the female connectors? I just filled the tank, and I do not feel like draining it for the umpteenth time. I have a new petcock kit coming, so I will clean the fuel gauge, run new wire and see if that will fix that gremlin.


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#4 ·
Insulate the terminals by wrapping electrical tape around them and the relay. If the relay is loose and the bike only shuts off going up/down hill as you said in your previous thread the relay may be swinging and shorting against the frame.
 
#5 ·
I will do that. The relay is tight though, and it felt like it would break if I pushed on it much harder to move it. It shuts off when turning the handle bars. So I think something is being stretched and grounding out.


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#6 ·
If the relay pins are exposed it might not take much movement to short it open. Wrap it and try it.

If no improvement, back to the wiring under the neck covers. You mentioned corroded wires. It may be you have a wire that is broken in the insulation and not visible as exposed. When you turn right it pulls apart in the insulation.
 
#7 ·
If the relay pins are exposed it might not take much movement to short it open. Wrap it and try it.



If no improvement, back to the wiring under the neck covers. You mentioned corroded wires. It may be you have a wire that is broken in the insulation and not visible as exposed. When you turn right it pulls apart in the insulation.


It is grounding out the starter. The button does nothing after the relay clicks. I have insulated the whole mod very with electrical tape, but nothing works. The battery jumps up to 14vdc on idle and then drops to like 13.5 at 4K rpm. Thoughts? I have the stock r/r


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#8 · (Edited)
Working from faulty memory here. I think the coil wiring shows connecting the positive coil wire to the relay and on to the coils as connected to the starter relay positive. Try connecting that wire directly to the battery. Leave the relay trigger wires as is.

14v at idle when just started RR may be recovering the battery and then reving it is clipping voltage to a lower charging rate. If you battery shows 12.8V after sitting idle for 24 hours I wouldn't worry about stator/rr for now. Let's find the starting problem for now.

BTW, is the RR still under the battery box?
 
#9 ·
Yes it is still in the stock location. I have the red wire that connects the two coils wired directly to the battery. That was the mistake I made before, I had it grounded


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#10 ·
About the battery voltages are those readings from when the bike would start?

Is the not starting intermittent or solid failure now?

Have you checked the battery voltage after sitting for a couple of hours. If so what was it? You have a wet cell battery if I recall correctly.
 
#11 ·
About the battery voltages are those readings from when the bike would start?



Is the not starting intermittent or solid failure now?



Have you checked the battery voltage after sitting for a couple of hours. If so what was it? You have a wet cell battery if I recall correctly.


That was from when the bike would start. Before starting, it is at 12.38 and has been going up from there. That was after letting it sit for a few days. Yes, it is a wet cell battery. I wiggled all of the wires with the bars off to the right, to no avail.


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#12 ·
OK, you've wiggled the wires with no result.

With the bars to the right and the ignition on, are all the front lights, instrument and dash lights on?

With the run switch on an you hit the start button does the starter relay click?

Do you have a 3 amp charger? Can you charge the battery? Are all the cells to the full mark? O'Reiley's can load test it. And they have an AGM motorcycle battery for 85 bucks. I just had to replace mine.

After that it's back to tracing wires one by one for an open or short. All black/yellow should show ground.

If I recall, you don't have a meter just a continuity light. There' a way to use that but it's nasty! 8~)
 
#15 ·
OK, you've wiggled the wires with no result.



With the bars to the right and the ignition on, are all the front lights, instrument and dash lights on?



With the run switch on an you hit the start button does the starter relay click?



Do you have a 3 amp charger? Can you charge the battery? Are all the cells to the full mark? O'Reiley's can load test it. And they have an AGM motorcycle battery for 85 bucks. I just had to replace mine.



After that it's back to tracing wires one by one for an open or short. All black/yellow should show ground.



If I recall, you don't have a meter just a continuity light. There' a way to use that but it's nasty! 8~)


All of the lights are on. I took apart the starter switch, which had corrosion, and cleaned that. So when I hit the spot on the range of motion (not all of the way to the right, it’s just a small little sliver that you can see in the video), the starter button will not work. Up until and past that, it works as it should. I will throw it on the charger, and I got a multimeter yesterday. I will have to get the agm, but this bike is turning into a money pit lol. I still need the brake lines, turn signals and fork seals. I have a new petcock rebuild kit coming, so once that comes in, and the tank is empty, I will take the tank off.

I also want to check the coolant lines when I have the tank off. It seemed that someone poured a ton of oil in the coolant reservoir. The rear cylinder coolant drain was plugged when I flushed the system. I think running the bike has dislodged the sludge, as there’s a film floating in the reservoir tank. Since I have had it running, the temp stays in the center, so I don’t think head gasket. I will reflush the system again.


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#16 ·
All "project" bikes are money pits. Mine was but when finished you'll love it. I do mine. Once I got past the noise these VN750 engines make that is! 8~)

With the bars at the dead spot continuity check all wires to start button and the run switch to see if you have an open that is pulling apart under stress.

Disconnect the battery, make sure the cells are topped off and charge it fully. Meter the voltage to see what the initial charge is. Let it sit disconnected for 4-5 hours for the surface charge to bleed off and meter again. Less than 12.8 is a weak battery.

The AGM battery seems to cure other issues. These bikes love volts at starting.
 
#17 ·
For diagnosing starting/running issues I find it way better to just hook the bike up to a car battery with the car turned off. Those big car batteries can start the bike several more times and with better cold cranking amps than even the AGM batteries. That was how I figured out my last AGM was bad, and confirmed that there were no other electrical issues than the battery.

In this case it doesn't seem like the battery is necessarily the culprit, but may be discharged right now.
 
#18 ·
I don’t think the battery is your culprit either but it could just be a casualty. When my stator died last month I needed a few jumps to get the bike the 20 miles back home. That and I’m sure it sat long at the dealership where I got it fixed seemed to kill it. I was able to charge it but it didn’t hold it as well as it did before the stator crapping out. Using the bikes battery to troubleshoot electrical issue will strain it for sure
 
#19 ·
Not to sound stupid, but I thought it was a 12v battery, so wouldn't 12.4 volts be spot on? I took it out tonight, and I think it is working the bugs out of the drive train. It is actually much more snappy than it was at first. I will take the tank off soon. I also saw the emgo wide swept handlebars. I wanted something that was similar to the road king (I think the handle bars feel perfect), so I am hoping these are it. Once I get back from my vacation, I will order those, and will probably have to lengthen the wires to get them to fit the wider handlebars.
 
#21 ·
I'll be honest i skipped reading the thread because all 5 of my VN’s have done this and 100% of the time it’s been the ignition switch. If you think you’ve found the issue elsewhere, you may have found the OTHER issue..... but i guarantee you’ll find out your ignition switch is going bad eventually when another problem arises in the future.

When the bars turn the switch plates push away from each other (they are sandwiched) when the wires push or pull.
 
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#22 ·
And shooting something like wd-40 in the lockset will fix this?
 
#23 ·
Yes, usually if the bike dies turning the bars to the right, there's either a bad wire in the harness where it bends around the steering neck, or there's an exposed wire in the headlight thats grounding out on the headlight shell (its plastic, but metal coated) or there's a bad wire in the ignition switch.
Rebuilding the switch and checking the welds, along with checking and isolating the wires by wrapping them in plastic wrap usually cures the issue.
Rarely is it a broken wire in the harness.

Spraying the switch with WD40 can help with stuck or dirty contacts, but this would be problem that bar position shouldn't impact.
 
#24 ·
Well the damned thing died yesterday, after running well around town. The tank is about empty, so I will be pulling it again once I get done mowing. I will check the neck. I will use this time to replace the radiator hoses on the top (the one is leaking where it enters the rear cylinder at the top), and see if I can’t figure out what is wrong with the gas gauge now. There just seems to be a ton of what I am assuming (hoping) are electrical issues. Also, I think someone put oil in the coolant reservoir. When I flushed the coolant, a ton of old oil sludge came out and the rear cylinder wouldn’t flush. Running it now, there’s a little bit of oil in the reservoir floating on top, but the temp stays steady in the middle. I am hoping the heat has loosened everything up. It sat for 19 years and never moved.


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#25 ·
UPDATE: After much tugging and turning the handlebar, I believe that it is in the big wire bundle going into the headlight. My front turn signals stems were broken, so I cut off the old ones. I checked the bundle the first time I was in there before discovering that is where the problem lies, and it looked fine. I will dig into it more tomorrow. The fuel gauge works, but the float is bad. So that problem is solved. Now to flush the coolant and see if the oil returns again. It was much less oil than when I drained it after sitting for 19 years, so I am hoping this is just residual oil that was stuck in the reservoir/lines. Do you think the lines will should be replaced? I pulled that metal tube off of the rear cylinder where it leaks, and I was surprised by there only being a small gasket.
 
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