You can a pretty good one at Radio Shack for under $25.00

 

I have, took a class session on winterizing your motorcycle and they pointed out that you can't keep the battery charged during the winter by going out and starting up and letting it idle for a while because the RPM's aren't high enough to set up the correct charging voltage.
Not sure if it's true but they were Harley Service Techniains

 

They were right in telling you idle will not charge the battery, however at 1200 RPM and up, ( not 3,000RPM minimum) the charging system is producing enough amperage to supply the bikes needs as well as charge the battery.

 

I agree that it shouldnt matter if you use a car to jump it. I had the stator go out in my 09 FB with under 400 miles and the d--k at the dealer said I jumped it off of a car and they would not fix it. I did politely inform him that if my 3 day old bike would not start I would not jump it I would call them directly to come get their bike. Moral of the story?? I dont know???

 

I had always thought that a car alternator charges when it's reving up as well, However, I read somewhere the other day that a car Alternator actually charges on the deceleration so it doesn't rob as much horse power from the engine.

I always thought that as long as the two systems were 12 volts it didn't matter. But when I jump a bike off of a car i always hook the Negatives to the frame and not directly to the battery. Just always heard to do it that way on a bike???????

 

FYI:...Just another note on this method of charging the battery.

You shouldn't start your bike in the colder weather for short periods of time, like to charge the battery.
The reason why is that the engine heats up a bit but doesn't stay at operating temp long enough to burn up the condensation that builds up in the motor from the engine heating and cooling down.
Normally the condensation is turned to steam by the hot oil and pumped out the crankcase vents to the carb and then burnt up in the motor during normal driving.
After a couple of these short period running sessions you will have moisture build up in the oil that will have that milky look to it.
(Kinda like it looks on a cars dipstick when it has a blown head gasket. (water in the oil)
It will start to form first where you can see it, on the top inside of the dipstick.

I know this because it happened to my brothers bike when he took it to work all last winter. It was only a five to seven minute ride to his job each way. It drove us crazy trying to figure out how water got into the motor since it is not water cooled and he didn't power wash it.
After alot of research on the internet and confirming it with a trusted mechanic, we got the answer which is what I just described.

 

Time to install a kickstart kit Mike. I called Allen HD to see if I could have mine serviced in Garland under my contract and they said no.

 

DO NOT tell them you jumped the bike with the car running.. just tell them you have a problem with the battery going dead..

 

up until here recently cars charge all the time regardless of whether the eng is accel or decel.. now hybrids are another story.. they charge on decel only.

i know honda is experimenting with a clutch drive alt so it only charges at higher rpm's.. it won't be long and we'll be getting dumb *** complaints of dim lights and low blower speeds at idle..

 

Cars alternators charge normally charge at a higher voltage then a bike. 13.8 to 14.7 give or take a few points. bikes charge in the low to mid 13's. They say you can jump with a car but not with the engine running. Yes always put the neg cable on frame. idle will not charge the battery.
if the car is running when you connect the bike the voltage will dip for a moment and then try to stabilize and go slightly high for a moment. The moment of low voltage will increase amp draw which can cause damage(like that blown bulb). The moment of high voltage can also cause damage (like stater or regulator damage). That's why a bike doesn't do full charge till the rpm go up. It won't have the low voltage issues at idle and have to rev the engine itself to assist regulation. The regulator on a bike just keeps the voltage down which is easier