Topic: jumping / charging battery on CB550f

[whoismattclark]

My $20 trickle charger was stolen out of my garage a few weeks ago, and now before I go out an buy another -- which might just get stolen again...I'm in an apartment complex, you see -- I was wondering if I could use this portable gizmo which was just given to me as a present.

http://www.toolrage.com/prodView.asp?idproduct=561


I'm working on getting this bike running, so this would be just a temporary fix while I try to start her up.  It's not meant to recharge the battery after sitting without riding.  Once I get her running, she'll be ridden enough not to need the trickle charge.

[lawrence]

How many CCAs' is that charger rated at?
My friend, who had a 71 cb750 rat bike, once drove 3 miles back to his house, with one of those portable jumpers taped to his seat, with the clamps electrical taped directly to the leads, and no battery. After that rig his bike still charged better than mine. And that was weeks after our group ride  50 miles north of Seattle to the Tulip festival in which our little group played the game, "Keep Skippy's CB Going", where almost there and back we had to all stop and put out the electrical fires in his handle bars (thus the "Rat Bike") I think we used the horn and start button wires to keep ignition, it was great fun!!

[whoismattclark]

I don't have much info on the DC power supply gizmo, but maybe this will help:

Boost Power=400 Cranking Amperes
Peak Ampere Power=900 Amperes

Fun story, thanks for your reply...MDC

[Ibsen]

To be on the safe side. If you have an ordinary car battery, that would be a better alternative for jump starting. But it should not  be in a running car. A car generator will put out to much power.

[Badboy]

It has been a while[2.5 months] that the original post was made, but what we are looking at is one of the best backups you can get for battery problems. It is a ncad setup and will start any thing from a lawn mower to a small diesel. We have a couple in the garage where I work . They have a lot of umpth. Good investment for your car or whatever[in your car it might pay for itself in towing charges]I don't think you would what to carry it on your motorcycle though,it weighs around twenty pounds or so.
The snap-on dealer brought one around the other day that had an inverter on the back of it[so in a pinch you could use it to shave with or watch the news !].

[Paul]

I've used this on my 500 on many occasion, whilst I was trying to get my own battery to hold a charge.
I've never had any problems with it. From what I can see if it's 12V the bike will suck in what it needs to start, then remove the leads immediatly. Remember when jumping put the ground lead on the frame, not the battery.

Exemption clause....the writer takes no responsibility for any damage caused whilst trying this excersise)

[SteveD CB500F]

Remember when jumping put the ground lead on the frame, not the battery.

What's the technical reason for this. The frame is connected to the battery (isn't it?)

[Paul]

In theory one is supposed to connect the negative at least 10 to 12 inches (25 to 30 cm) away from the battery. This arrangement is used because some sparking will occur and you want to keep sparks as far away from the battery as practical in order to prevent a battery explosion from the gas dissapated. 9I've never seen it ........but I don't want to either.

[Raul CB750K1]

This subject has been discussed before a thousand times and still it seems that there are many misconceptions.

1. From a electrical point of view, no matter if you connect the negative to the frame or the battery lead. The only important thing is to get a clean surface and a wide contact surface.

2. The spark caution makes sense, but a battery will only generate hydrogen while charging (the famous rotten egg smell), so no way of getting explosions on a discharged or stationary battery.

3. When connecting the leads, it's good to connect the positive first and then the negative. That way, if you unintenionally touch with the clamp any part of the receiving car there will be no short circuit as both chassis would not be yet connected. If you later make a short circuit with the negative lead there will be no problem as chassis and lead will be at the same potential (strictly speaking, that would be no short circuit at all). Remove the leads in the reverse order: first ground, then positive. Believe me: I once made a short with the spanner and it melted in the contact point. That can be DANGEROUS.

You can jumpstart a bike with a car battery or with a heavy duty truck battery, as long as it is 12 V. The power of the alternator doesn't matter as it is only given on demand. I can crash an empty beer can if I want, or simply hold it without damage. My 2 year old daughter probably can't crush the beer can (why should her?). I hope the analogy is clear    The alternator provides 12 V to hold the charge of the battery. If the charging current is high you will need a higher power alternator.

Strictly speaking, when you connect the jump cables you are connecting two batteries in parallel to the donor's alternator. It needs to have enough power to charge both. If we consider that the donor's battery is charged, all the alternator power will be available to the bike battery, but the voltage will still be 12 V.

4. I don't have one of those gizmo's but they seem pretty convenient. Anyway I always carry jump cables in my car. I have been donor three or four times, and receptor a couple of them. I don't mind to ask a foreigner to jumpstart my car if I have the cables.


Regards


Raul

[dpen]

First thing we were taught in the dim, long ago apprenticeship days was never to take electrics for granted. Even an almost dead battery MAY have a small amount of hydrogen gas present.
For safety reasons (as mentioned-eliminate any sparks) connect the negative lead to something metal & handy (seat hinge, rack, numerous possibilities).
It may never happen, but, you don't want to be a crispy critter, or worse, damage your bike.

[Raul CB750K1]

Yeah, every precaution is not enough. I've seen many mechanics warning me about safety at work, while smoking their cigarettes in that oil-and-gas environment... 

[TwoTired]

To be on the safe side. If you have an ordinary car battery, that would be a better alternative for jump starting. But it should not  be in a running car. A car generator will put out to much power.

ugh.  This ficticious rumour needs to be quelled.  As, the old wife that started it has already been amused far too long.

Power is an equation,  Amperage times Voltage = Power (watts)
Auto alternators generate about 14V @ 30 Amps (Really big ones put out 60 Amps)  so, that's 420 watts  (or maybe, 840 watts).

Car batteries generally have at minimum 400 CCA (Cold Cranking Amps) (footnote 1) And, they are often bigger, 600, 800, 1000 CCAs or more.   7.2V X 400 = 2880 Watts  (I'm being very conservative here)

Even the smallest car batteries far exceed the power of the car's alternator when fully charged.


Footnotes:
 1 - Cold Cranking Amps
Cold Cranking Amps is a rating used in the battery industry to define a battery's ability to start an engine in cold temperatures. The rating is the number of amps a new, fully charged battery can deliver at 0° Farenheit for 30 seconds, while maintaining a voltage of at least 7.2 volts, for a 12 volt battery. The higher the CCA rating, the greater the starting power of the battery.

[Badboy]

A couple of times in my life ,I have seen a battery that was blown apart. The party was charging it and removed one of the leads while the charger was still turned on . It blew the top right off. Big battery to. The reason to put the negative away from the batt is to avoid this,it can hapen . Hydrogen gas is powerfull stuf. Beter be safe than mess up your cycle or maybe your face!

[keiths]

We had a battery blow up in our van. It was sitting in the hot sun all day and it exploded when the key was turned. It sounded like a bomb. The acid peeled the paint off the inside of the hood.

[TwoTired]

One thing I noticed not mentioned in this thread about those battery jump boxes is: the batteries wear out in the boxes, too!  Nicads should be cycled and charged reqularly to maintain their functionality.  Even then they will wear out in about 5 years.  So, if you get one of these, just be prepared for another machine to maintain.

Cheers,

[oldbiker]

Current drawn by a load  is dependant on the applied voltage and the circuit resistance (or impedance in an AC circuit) so it doesn't matter how much current the source is capable of supplying. The load ie. your bike that you are jumping will not be damaged by jumping from a car or truck.

[Badboy]

They are still real handy to have around. We use them all the time in the garage.

[dpen]

Look after them. we have one in each breakdown truck (12v, 24v), used mainly for trucks & buses.
One is reliable, other required new batteries after a year.
As mentioned, another mechanical thing to be maintained properly.