Don't jump start a bike off a car battery

[nwujames]

<<CORRECTION>>Don't jump start your bike off of a car that's turned on - the amperage difference will fry your bike's battery, and maybe the electrical system too.

[longbeachgary]

I've heard that you can jump a bike with a car as long as the car is not on.

[NYcruiser]

i just did it recently... worked fine... not MY bike though

[nwujames]

I don't think so - the main issue is that there is a large amperage difference...

[longbeachgary]

There is no voltage difference, they are both 12 volts

[Norm]

Just thinking, could it have fried because the cables were not hooked up correctly?

[nwujames]

Well, I wasn't there so it's a possibility - I'm just hoping he'd know better than that.

[Frankt07]

i believe what might happen is the same as connecting a generator to your house while the light company is still powering it. the power company will push the generator voltage and current back and blow something.
same thing with the motorcycle and car charging systems. the cars system is designed to put out over 100 amps in most vehicles due to all teh electronics. all we have is a few dozen amps.
we can jump start off of a car battery, but the car must be off

[nwujames]

Originally Posted by Frankt07

i believe what might happen is the same as connecting a generator to your house while the light company is still powering it. the power company will push the generator voltage and current back and blow something.
same thing with the motorcycle and car charging systems. the cars system is designed to put out over 100 amps in most vehicles due to all teh electronics. all we have is a few dozen amps.
we can jump start off of a car battery, but the car must be off

That sounds about right. Thanks!

[AutoTech1]

Originally Posted by nwujames

So it's a cold morning and your bike doesn't feel like turning over.... Learn to bump-start it and DO NOT go for the jumper cables from your car trunk. The voltage on your car battery will fry your battery, potentially a fuse, and maybe even your electrical system. Just thought I'd pass that along, since unfortunately one of my buddies just learned the hard way.

I'm not too knowledged with bikes, but what I do know is strictly about cars. You said it was a cold morning right? How cold was it? Because if it's pretty cold and you give a battery a huge charge you can kill it that way. Which is why in the automotive world, when we charge batteries, we start at low voltage and slowly rise up... But I don't know. It could be a thing with bikes, so don't qoute me on that... I don't know too much about bikes yet. And if it's really cold outside and you just shoot a battery up with high voltage, it can become a bomb too and explode. :-/

[elr658]

Uhhhhh Dude, you mean AMPERAGE.

Mark L.
ASE Master Auto Tech
Mitsubishi Senior Tech
CT Certified Emission Inspector
Former bike shop line tech and Service Manager.

USAF A-10 Master Avionics Tech AFCS/Inst

Annoying Internet Know it all.

[AutoTech1]

Originally Posted by elr658

Uhhhhh Dude, you mean AMPERAGE.

Mark L.
ASE Master Auto Tech
Mitsubishi Senior Tech
CT Certified Emission Inspector
Former bike shop line tech and Service Manager.

USAF A-10 Master Avionics Tech AFCS/Inst

Annoying Internet Know it all.

Sorry. It's my first year in AutoTech and I'm in highschool. That's what I meant though.

I wasn't trying to be a "know it all though." I don't know it all. Lol. I'll admit that. I was just trying to help out. Have to learn by making mistakes anyways.

[zedx11]

if you look in your owners manual it tells you how to jump your bike. red on pos black on neg of jumper battery, red on pos of bike and black on foot peg or other clean metal piece of your bike.

[robrider]

I left my lights on the other day and used one of those booster packs to get it started. No problems at all...

[elr658]

And I'M the annoying internet know it all! (Or at least around here.)

[nwujames]

hey, as long as you're right, it's all good

[tawd]

You cant burn anything up by jumpstarting a motorcycle with a 12v system from a car. The car having a higher amperage charging system will NOT hurt anything. Voltage is whats important, not amperage.

[78_KZ750_Cafe]

Whoa there tawd, where did you get your electrical engineering degree? Amperage is definately the main issue in jump starting a bike with a car system. The amps are the maximum flux of power, sort of like how fast water flows through a pipe. voltage is the electrical potential - the amount of water in the tank. running higher amperage through a system than what its designed for will eff it up pretty bad - push a lot more water through a pipe than the pipe can handle without bursting. that said, you CAN jump a bike with a car battery, just don't have the car running. The batteries current is limited but the alternators is much higher. you don't want the current from your alternator frying the circuits in your bike.

[MONSTERKAWI]

was the bike a 6 volt set up whereas the cars are 12volt?

[nwujames]

He had a 250cc crusier-lite. Not sure what the voltage was on his batt.