Battery??

[pos-tech]

So electricity and I have never been good friends, so I was hoping someone has a good idea. I have a 77 gs750 and the goal is to either eliminate the battery or at least make it really small(so I can hide it under or in the seat).I plan on using the kick start to start it, but in order to start it needs juice to run the ignition. I read about someone who replaced the standard battery with a small sealed lead acid battery on a gt750, so I thought it was a good idea, so I found a 12v 2.9 amp/h lead acid battery I had lying around, but it was dead, so started the bike on the normal battery then swapped over to the small lead acid battery, I let it charge for about 5 minutes, killed the bike, and there was planty of power to restart the bike. That is when the trouble started. I revved it and the headlight got brighter, which is something I am used to, then I revved it higher and the headlight got really bright then really, really dark. The tail light lasted a bit longer. It seems to me that the smaller battery is not absorbing enough juice or the bike is putting out too much juice, any ideas on how I can make this battery work, or find another battery that is small(so I can hide it under the seat).
Thanks

[Anonymous]

So the question now is "did I damage anything"? Now go back to the original battery and see if everthing is back to normal or not. One of the batteries functions is to act as a big sponge to absorb and damp nastyness. If your battery is to old(which makes it like a small battery) or low on fluid, bad things start to happen and damage the components which expect the larger healthier battery to be there. Personally, I think you are playing with fire but if you insist, try as big a capacitor as you can fit along with the battery you want. Good luck.

[Keith Winter]

Oh boy,
Did you disconnect the battery with the bike running? You may have fried your rectifier by doing this. This means that you may have been getting unregulated AC going to the battery and this would be bad. Also any sealed battery can not withstand any kind of over charging, they have been known to blow up as a result of being over charged. This applies to both "gell" batterys and the more common "wet blanket" type that is found in most car's these days. As all fixed output alternator systems like our old bikes have will always charge a little to much into the battery no matter what R/R you have, you should not use a sealed battery unless you know for sure that it's not being over charged. Also, like the last post states, the battery has to absorb the excess voltage, DC and a little AC, so the one you tried was probably not "big" enough to do this. This can also lead to meltdown as well. There is no adjustable field regulation on old bike's (like a car) so the balance between to much and not enough voltage/ amperage is hard to get. Without revamping the entire charging system, you may not be able to do what you want without burning things up on a regular basis.
Keith

[pos-tech]

so it's official my idea was bad, but does anyone have any good ideas??

[themess]

battery

Start by assuming that Suzuki's engineers really knew what they were doing when they designed the motorcycle. They designed the electrical system to work best with the stock battery. Return to the stock electrical system. If you fried some parts, replace them with stock parts.

Don't change the elctrical system unless you've taken a course in electricity. You need to understand voltage, amperage, and resistance; the difference between DC and AC and how AC is converted to DC, how to read and use wiring diagrams, the function of solenoids and how they are used, how to use a multimeter, how to size wires, connectors and soldering.