with a motorcycle to charge that battery you need to ride for a while, everytime you ride the battery charges.

 

The problem isn't jumping the bike from a cage. The problem comes from jumping the bike with a cage that is running unless it's something along the lines of a Goldwing or BMW that actually has an alternator with a huge charging system of it's own. In general, the cars charging system even at an idle puts out way more than the motorcycles charging system would even dream of outputting and because of this you stand the chance of frying the bikes system. Additionally, the cars battery will put out more than enough power to jump start a bike so there is no need to start the car in the first place. .

 

The average HD battery should have over 300 cold cranking amps, 2000 up FLs are over 400. The average car charging system is probably around 100 amps, some severe duty systems would be 140 plus and some ambulances use 2 alternators. The max possible output is not the danger of jumpstarting your bike from a car as none of them could exceed what a good battery could do. The danger is voltage spikes or grounding as the circuits are very sensitive on newer electronics. The bike would have to put a load on the charging system for it to increase amperage output.

 

I've jumped my bike numerous times with no probs. As stated before, the car is a 12v and so is your bike, so no it won't hurt it none. Get the AGM batt from Harley, it's the only thing I buy from them. They generally last 4-5 yrs. I had one and never put it on a batt. tender for 3 years and it gets 100+ deg. in the summer for a good 3 months, when it finally started to give me probs I put it on a tender and it lasted another year. They are pricy batteries, but as the saying goes "you get what you pay for".

 

uummm

As a matter of interest. It's not the voltage in this case, it's amprage. Actually most modern automotive charging systems are 14VDC anymore.

However, my truck came stock with a 800cca (cold cranking amp) battery, my bike's is something like 220 (not a harley). So if you jump it off of running car a you are risking at the very least blowing a bettery cell, if not the regulator, ignition ECU ect. The bikes electical system does NOT have sufficient resistance to keep the availabe power from blowing out parts stuff. Power (in watts is a fucnction of voltage times power IE=P(watts) Current is voltage diveided by resistance.... In this case you are running the bike's electrical system in parallel to whatever the vehicle is, in a parallel circuit CURRENT is common, so you are going to eat whatever the automobile's normal operating current is what the bike is going to eat. That's a brave propisition with a fuel injectied bike.

I've jumped a bike off of the non-running car before, with my old shovel, but that was more of a get the bastard going becuase the a battery terminal rattled lose thing. The real pisser there was that I had JUST changed to primary and removed the kickstarter the week before.....irorny at it's finest.

 

There seems to be some confusion here on this subject.
The facts:

• The only concern about jumping your bike with a cage is 'voltage'. Your bike has a 12 volt electrical system and so does your cage, so it's okay.
• 'Modern charging systems' will supply between 13.6-14.6 volts to the electrical system when the engine is running. (provided the alternator is functioning correctly) This is true also on your bike.
• If you put a volt meter across the battery terminals without the engine running, you will get approximately 12.5 volts (providing the battery is in good shape) Start the engine and the voltage rises to around 14 volts if the charging system is working.
• CCA (cold cranking amps) is only a function of the load that the battery is capable of handling. Your truck requires more cranking amps then your bike does, hence the 800 cca vs. 200 cca.
• The amperage present in a circuit is a result of the load placed on the circuit. I.E.- A motorcycle starter places a much smaller load on battery than a truck starter cranking over an 8 cyl.
  • In your house, a typical outlet is rated at 15 amps, a single 60 watt light bulb draws .5 amps - the lightbulb is not being hit with 15 amps even though the outlet is capable of producing 15 amps. That's because the load placed on the outlet dictates the amperage. Too much load with trip the breaker.
• Just because a battery has 800 cca's, doesn't mean that jumping a bike with it is going to blow anything up with 800 amps. If so, then how do you explain the fuses in the system that range from 2-30 amps that don't blow in your truck?
• Because cars and trucks have batteries with higher cca's, you can usually jumpstart your bike without having to start the car, however, if you start the car, it will not hurt the bike.
• JUMPSTARTING A MOTORCYCLE WITH A RUNNING CAR IS OKAY TO DO!!!

 

It's your bike, treat it as you will.

I was refering to the power that would be common by say, hooking a car to a bike then starting the car.

While you are right that the 800cca is only a start up condition (more like a hard value that it rarely sees), the the average running current on my F-150 with all the lights, AC and other electic crap that you can't seem to get away from anymore FAR exceeds the the normal operating range of a motorcycle charging system.

The 5, 10, 20, 30 ect amp fuses throughout most of the vehicle are electricly issolated from the charging system (which is traditionally where the alternator battery and starter live), go look up how voltage divider networks function. By the way voltage is only a circuit common value on a sequential application, which any motor vehilce is not.

When I was messing around with the light and relays on my Triumph I noticed that the charging system was only designed for a nominal 55 amps, when I pulled the manual for the truck the it was over double that.

Now you are right that CCA is start up load. However once you have both engines running you now have a two branches of a parallel circuit, and the automobile is generating WAY more current, since CURRENT DIVIDED BY RESISTANCE DETERMINES VOLTAGE this doesn't simply appear in a void the common CURRENT that the motorcycle's electrical systems is going to be presented with is going to be that of the automobile NOT the bike's alternator and at that point you are risking electrical damage. The bikes system regardless of the load presented is GOING to see the higher current, electricity follows the path of least resistance.

There are numerous types of circuits. In a simple sequential cuircuit voltage determines because it is effectively a daisy chain source to ground.

Remember Ohm's law is I=V/R, do what you will with it but it is the basic law of physics that everything electical is derived from.

Because in a parallel circuit resisistnace between branches from any one source is divided by the number of brances this is is where you run into issues.


Edit: In the interest of being more civil, yes, you can jump a bike off a car battery without damage providing it is not running. I've jumped mine off of other bikes, cars, a forklift and a tractor (I did ride a shovelhead) without damaging anything other then the battery that I already knew was pretty much toast.

 

What he said.

 

Its either the battery or the starter clutch, when you start the bike hold the start button in until the engine is firing, its designed to disengage, if you pull your finger off the start button too quickly and the motor "kickbacks" you will most definitly break the strater cluch in two, the shaft is hollow and won't tolerate a kickback.
I found this out the hard way, thought it sounded cool when I pulled the finger off and it kinda backfires as it starts, kinda cool to spend 3 hours and $125.00 bucks to replace the starter clutch on my '03 roadking.

 

You only assumed that starting the other vehicle would damage your bike, so you didn't prove the theory. Others on this thread have jumped their bikes with the car running and their batteries or their electrical system didn't explode. Seems that they already disproved your ideas concerning charging systems.

Not trying to be a jerk about things, but you can easily prove what I'm telling you by utilizing a volt meter, ammeter (the clamp on style) and see for yourself what your truck's electrical system is doing compared to your bike's. Measure the voltage with the engine off and then with it running. Then measure the amperage as the engine continues to run. As your battery recovers from staring the engine, the amperage will taper back. Watch the amperage as you turn on your headlights, a/c and other electrical devices. It will increase as the load demands the current. Hook up some jumper cables to a riding mower if you don't want to try it on your bike, leave the mower off, start your truck, turn on all your accessories (on the truck), measure the amperage across the jumper cable and then the battery cable on your truck. I gaurantee the readings won't be the same. Only the cable on your truck will see the load, not the jumper cable. Prove it for yourself, then get back to me.