I fried my wifes bike

[Rut Row]

either way you mess up the wifes bike and you won't get fu@#ed

fixed...

[mdubya]

Should be an easy fix with a fuse. I do believe the worst damage you might do is to cook the dead battery or melt a connector. I have jumped plenty of bikes off of a car or truck battery. As said above, do it with the car or truck off. I even assisted an EE who connected my truck's battery directly to the disconnected battery leads on a bike. My truck was off. But we started the bike connected directly to my truck's battery. No harm, no foul.

BTW-Battery Tenders are cheap and easy to use.

[zamobro9]

i have a battery tender, just no electricity to my shed. the DAMN battery was purchased in july, thought it would have still had juice, oh well thanks for the suggestions, the truck was off when I did this

[the dude himself]

You can push amperage. That is what voltage is for. The difference in voltage of the 2 batteries will determine the amperage. If your dead battery is at 2volts and your charging battery is at 15volts. That could be a disaster. The lower amperage you use to recharge the battery the better. Low and slow.

Amperage is the rate of flow of electrons through a wire. Devices can draw amps, ie use a certain amount at a constant voltage, but a 1A device on a 20A circuit won't burst into flames. It can't draw the other 19A.

And while voltage is the difference in potential of the circuit, it can't be increased to increase the amperage. The opposite is true - that's why line voltage is stepped up to 110kV for transmission, then reduced via transformers before entering our homes. If we tried to carry 110V from the power plant the cable would need to be huge to handle the resistance.

A device that requires 20A, or a dead battery, is capable of using up to 20A if the voltage is raised high enough. A dead battery at 14.4V won't draw more than 10-20A - well below the main fuse (30A). Of course, reverse the polarity and you're looking at a quick 40A load - hopefully the main pops before the diode hits its breakdown voltage.

Regarding charging the battery:

The best battery charger is a power supply that can be current and voltage regulated. There are some super fancy automatic ones that incorporate these features. Based on the chemistry of a battery, there is a MAGIC voltage where it can be left connected and it will not overcharge, and its internal leakage will be compensated for, keeping the battery fully charged all the time. This is called trickle charged or "floated", but most so called trickle chargers are junk, not voltage regulated and really just slowly boil away the electrolyte with electrolysis, making certain it will be a "late" battery when you actually need it.

To properly charge a battery, you should apply a voltage that causes current to flow (being careful to get the plus and minus hooked up properly!) at about 1/10th the amp/hour rating of the battery to a maximum of about 1/4th the amp hour rating of the battery.

For instance, for a 45 amp/hour battery you should not charge much faster than 5 amps. For a 12 amp/hour motorcycle battery you should not charge faster than about 1.5 amps, etc.

When the voltage required to maintain this charge rate exceeds 14 volts, you should turn it down and regulate it at 13.8 volts. Just let the charge rate drop naturally while the voltage is held constant at the battery terminals.

Eventually the current into the battery will drop to practically nothing at 13.8 volts if it is lead/acid. Different chemistries will have different magic voltages. This is what is called "float" charging a battery. Maintaining it at a voltage which just balances the electrochemical potential of a fully charged series of cells, just below where they will start to perform electrolysis on the battery solution. If done correctly such a float can go on for a very long time and the battery will stay healthy, just compensating for the internal discharge rate of the battery.

http://www.chem.hawaii.edu/uham/bat.html

I looked over the schematics for the DR200 and if the fuse is still good I'd check the ignition switch and diode.

[frogman1981]

I wouldn't charge it more than the stator puts out. I'm guessing about 100w max (about 8a). Alot less than 20a. After the headlight uses 50w (about 4a) .

[zamobro9]

It was the main 20 amp. Thanks for the DAMN info

[bonehead]

Welcome back from the dog house