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Discussion Starter #1
I haven't reviewed how the battery and charging system interact so I don't know what runs off the battery and what runs off the stator.

I used to have a 250cc scooter that would jump start off and run on the stator, but the turn signals and brake light wouldn't operate. Still it would get you home with a dead battery.

I was just curious if my bat died if the Vn would run without one in it, IE- tossing the bad battery if it had a bad cell bringing the system down and running home without it.

Loved that scooter I had, got me home every time dead battery or not . Just jumped it off and took off.
 

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1986 VN750
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You can run with the battery disconnected (some have done it for troubleshooting). Not sure of the long term ill effects.

I've bump started my bike and rode home with a dead battery.
 
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I haven't reviewed how the battery and charging system interact so I don't know what runs off the battery and what runs off the stator.

I used to have a 250cc scooter that would jump start off and run on the stator, but the turn signals and brake light wouldn't operate. Still it would get you home with a dead battery.

I was just curious if my bat died if the Vn would run without one in it, IE- tossing the bad battery if it had a bad cell bringing the system down and running home without it.

Loved that scooter I had, got me home every time dead battery or not . Just jumped it off and took off.

Battery might last 5 hours or so... depends on how many lights you're using. The system is SUPER simple... basically the battery starts the engine running, turns the rotor and then the stator simply keep charging the battery full tilt with whatever its got. Anything that the battery can't use, is wasted into the heatsink of the R/R.


So basically you got this....in a nutshell...

3 wires of 3 phase 50volts peak to peak going into the R/R.
2 wires of 14..6volts coming out of the R/R straight on over to the poles on the battery. ( in an ideal world ).
Battery supplies everything unless the key is turned off, with only one exception.
The fan relay and the fan itself will both run regardless of the ignition key switch.

An "ideal" stator will put out about 336 watts if you are running at 8000 RPM ( according to the manual ). Your headlamp will pull 5 amps at 60 watts, though too.

Hope that helps.
 

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You can run with the battery disconnected (some have done it for troubleshooting). Not sure of the long term ill effects.

I've bump started my bike and rode home with a dead battery.
How did you bump started the bike?
Did you do it in second gear or first since it won't let you go out of neutral?
How fast were you going, running speed in a straight road or down a hill?
 

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Discussion Starter #5
How did you bump started the bike?
Did you do it in second gear or first since it won't let you go out of neutral?
How fast were you going, running speed in a straight road or down a hill?
It seems like I have been able to put mine in second sitting still with the bike off...... maybe I'm remembering wrong. Second would be much easier to make it start.
 

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It seems like I have been able to put mine in second sitting still with the bike off...... maybe I'm remembering wrong. Second would be much easier to make it start.
Ive tried it with a "slight hill". It just don't have the speed for my nubby legs... ;)

I suspect if you got the hang of it in 2nd or 3rd, it would be a cinch after awhile.
 

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The battery and r/r are basically in parallel with each other when the motor is running. Shouldn't be a problem running without a battery once the bike is started.
 

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Discussion Starter #8
I figured it out you can put it in first then try to push start it and when it doesn't work take it up into second. That seems to work just now by curiosity I was testing it
 

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The battery and r/r are basically in parallel with each other when the motor is running. Shouldn't be a problem running without a battery once the bike is started.
That's "hopefully" the case, and it depends on everything else of course, but by design, if it were otherwise, then the battery would always need to be charged after somebody rode the bike.

By the way... i finished that R/R for you last night. I'll probably post it up later...
 

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I figured it out you can put it in first then try to push start it and when it doesn't work take it up into second. That seems to work just now by curiosity I was testing it
The problem is, with the neutral finder, you have to get it rolling over in 1st, then hit 2nd while still keeping enough momentum/speed to do any good.

Hard to do alone, but have done it on the Kawi LTD with two people pushing.

Good to know though, bump starting is an option with a dead battery. I figured it might stall if you let it down to idle.

Wonder what happens if the fan comes on at idle?
 

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Discussion Starter #11
Random question.... How much amperage does the starter pull?
 

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1986 VN750
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It seems like I have been able to put mine in second sitting still with the bike off...... maybe I'm remembering wrong. Second would be much easier to make it start.
I was in second or third. I was being pushed in a CycleGear parking lot by a helpful employee >:)

Once up to full push speed I slammed down on the seat and dropped the clutch, reved, and pulled in the clutch. Took 3-4 tries.


Oh I also cranked idle speed to 2k rpm for the ride home. It stumbled a bit otherwise at lights and I did not want to be stranded.
 

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The problem is, with the neutral finder, you have to get it rolling over in 1st, then hit 2nd while still keeping enough momentum/speed to do any good.

Hard to do alone, but have done it on the Kawi LTD with two people pushing.

Good to know though, bump starting is an option with a dead battery. I figured it might stall if you let it down to idle.

Wonder what happens if the fan comes on at idle?

When i was having problems with the battery and she died on the way back, i pulled over and was on the phone half an hour or so trying to arrange for some help. Half hour later, just to see... she started right on up. The battery temperature is also something to consider besides the fan. As soon as you start up from a roll, that battery is going to be eating the juice from the stator as much as it can since its low. It will be pulling as much juice as either the fan or the headlight.

So a cooled down bike, would relieve the fan situation, and i guess you could just disconnect the battery since its a jump start . . .
 

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Is it possible to practice bump starting on a bike with a good battery, or maybe no battery?
That way when you find yourself in that situation, you won't have to overcome the obstacle of doing and learning it for the first time.
 

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FREEBIRDS MC CENTRAL NY
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Is it possible to practice bump starting on a bike with a good battery, or maybe no battery?
That way when you find yourself in that situation, you won't have to overcome the obstacle of doing and learning it for the first time.
Yup.
 

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Discussion Starter #16
I tried a few times unsuccessfully yesterday to see if I could do it out of curiosity and I didn't succeed yet. I can make mine go into any gear from still if I put it in first then kick it up a few times. I tried second and wasnt going fast enough.

I have a 10 amp power supply and I wonder if it is enough to start the bike if I ever have a dead battery.
 

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FREEBIRDS MC CENTRAL NY
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I could never get mine above 2nd
 

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without a battery in the bike, bump starting would be hard. you have to get the engine turning fast enough to get the stator/regulator putting out some juice, so the ign can be powered. not impossible, but hard
 

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So how does bump starting work? I know it gets the bike started on a dead battery but how does it do that?
 

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FREEBIRDS MC CENTRAL NY
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Basically you are using momentum and the bikes drivetrain to start the bike.the wheel will turn over the motor like the starter would
 
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