Jump starting
Stellar HDF Member
Joined: May 2009
Posts: 2,856
Likes: 127
From: Middle of Kansas
It is a very good practice to have the vehicle turned off when jumping lawntractors and motorcycles, or anything with a small battery/charging system. You do not need anymore than what the battery alone will put out, with out the alternator pumping it up to 15 volts or so. As has been said, going from small to small makes no difference, and you can leave the other vehicle running as long as its another with a same type system. Bike to bike, or lawn tractor to bike or another lawn tractor. This info use to be in the old Harley manuals I think.
Intermediate
Joined: Oct 2010
Posts: 31
Likes: 0
I have not done this on my harley, but back in my metric days I had to jump my little yamaha 650 with my car. Never turned the car over, had no problems getting the bike started, or problems with the bike post jump.
Road Warrior
Joined: May 2007
Posts: 1,635
Likes: 58
From: Bishkek, Kyrgyzstan
There are enough stories of fried starters from using a running car to jump a bike that it seems prudent to avoid the practice. Seems some get away with it and others don't. It's not the voltage that's the issue, it's the amperage.
The argument that a car alternator is only going to generate the amount of amps called for by the bike is apparently a sound one from what I've read but with all the stories about fried starters it's not something I want to take a chance with.
The argument that a car alternator is only going to generate the amount of amps called for by the bike is apparently a sound one from what I've read but with all the stories about fried starters it's not something I want to take a chance with.
If you don't feel safe doing it then don't do it.
That's exactly why it's called electrical theory, not electrical fact.
Road Warrior
Joined: May 2007
Posts: 1,635
Likes: 58
From: Bishkek, Kyrgyzstan
It should be created somewhere else, most commonly between the frames of the vehicles.
It's because the arc that CAN be created when the connection is made COULD ignite the explosive vapors coming from the battery.
We used to touch the bumpers together instead of running a cable between the negative posts.
Intermediate
Joined: Apr 2009
Posts: 31
Likes: 0
Jump Starting Using Battery Charger Connections?
I was stupid and left the ignition on. Not even a click when I came out. Jumped it from a buddy's bike with cables and four sets of needle nose pliers. It worked, but it was a PIA.
Has anybody ever thought about connecting the battery charger connections between two bikes using the HD charger extension cable? It might not be an immediate start, but maybe locking the running bike at 2k for a few minutes might be enough to crank the dead bike. A fist sized coil of extension cord beats a basketball wad of jumper cables any day in a saddlebag.
Has anybody ever thought about connecting the battery charger connections between two bikes using the HD charger extension cable? It might not be an immediate start, but maybe locking the running bike at 2k for a few minutes might be enough to crank the dead bike. A fist sized coil of extension cord beats a basketball wad of jumper cables any day in a saddlebag.
Road Master
Joined: Aug 2008
Posts: 1,018
Likes: 17
From: Southeastern Wisconsin
Do not start the car and jump to the battery is fine. If car is running, when you put load on (hit starter on bike) the car's alternator will kick out enough amps to possible harm the bikes voltage regulater, starter, stator. Just have the car shut off then all is good.
Another option might be to hook it up then go have a smoke and let it charge for 10-15 minutes then unplug and give it a go.
Another option might be to hook it up then go have a smoke and let it charge for 10-15 minutes then unplug and give it a go.
Road Warrior
Joined: Jul 2009
Posts: 1,431
Likes: 1
From: Calgary
Thanks for the tips. I guess I woulda' been a dumbass also because thats how I would have boosted my bike. Not anymore.
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Road Captain
Joined: Jul 2009
Posts: 583
Likes: 2
From: Eaton, OH
You can also jump from another bike if one is around. I have a set of jumper cables made just for that that I carry with me. So far I have have not had to use them.
http://www.yuasabatteries.com/accessories.php
http://www.yuasabatteries.com/accessories.php