Smallest battery

[Wack]

I currently use a Yuasa 12 v 7 ah battery to power an Acewell speedo, Stage 6 EGT and the horn, but may do LED brake light in the future. The battery is roughly 6"x3 x4" but would like something smaller so what's the minimum amperage I could get away with? Thanks

[Stevepshipley]

I think you divide watts used by volts and that tells you amps used. Amp hours is how long your batter will last on that drain.
(But I could be talking bolxxxs)

[MickYork]

but.......you also have the power/watts coming off the stator which is topping up the battery and giving additional power to what you are supplying.

I would have thought a 1ah battery would be sufficient to power the appliances you have mentioned but without knowing the total power consumption this is a guess.

[Knowledge]

Mick is right, the stator is constantly topping up the power while the engine is running.

To be strictly accurate, the stator is there to power the electrical system, and the battery is there to soak up surplus power or supply extra power on demand. The 7Ah rating means that the battery could provide 1A for 7 hours. Many of the items listed in your electrical spec use very little power; perhaps totally less than 1A.

I'd get the back and brake lights converted to LED though.

[MK Monty]

If you are running AC for lights and a trickle charge for the battery and your toys Then it will be a bit different to a full DC conversion when as above the battery is just a buffer. I have run all of the above with indicators and occasional full wattage pathfinder on a 1.2amp battery with no problems till I left the lights on in the shed. Those alarm batteries don't like being flat. but cheap as chips anyway

[Donnie]

ah but MK Monty are you on full DC with that 1.2 amp battery? I don't know if the original poster is on full dc or not as this will make a critical difference to his decision.

Personally though, if he's getting what he wants from his current battery Im unsure why anyone would bother changing?

[Mel K]

Ah but Donnie, it looks like , Wack, the O P, is after a smaller dimension battery, not neccesseraly a smaller watt or amp battery !

[MK Monty]

That was my point guys. if he is running AC then its only going to get a trickle charge so a larger capacity will last longer before needing a recharge. If he is on DC a different story. as pointed out he dont say what he has at the moment. this is the one I had used its about as small as they get.BUT im full DC
http://www.hardwarexpress.co.uk/np12-12 ... 1393-p.asp
Im using one of these on my special, it dosent foul the rear wheel and is 4 amp

[Wack]

Sorry chaps I should have been more specific.The reason I wanted a smaller dimension battery was to fit it inside a Diablo tank with the small toolbox but my existing battery would be too big to fit up against the back wall of the tank and the only size that would fit are the 1and 2 amp alarm ones.I'm on AC Varitronic and only use the battery as stated in the first post, the instructions for the digi units don't give the amps used.I already have an LED rear light but the brake light isn't that bright in poor,rainy weather so I'm told .

[MickYork]

In theory a battery is used to "store" energy. This means the actual running power is from the supply (stator) and the battery is only needed when the stator is not supplying power. If your appliances are drawing more power than the stator is giving out, then the battery will assist in powering them but only for a limited time as there is no spare power to charge the battery. Therefore....if your appliance's power is less than the power output from the stator then a very small battery will suffice.....if the appliance power is more than the stator output then a battery will give you more time to use the appliances but you will have to constantly re-charge the battery.......

[Nelly]

I wouldn't go too small with the battery as it's only being trickle charged.
None of the things you are listing is using a great deal of power, but the fact it's powering the speedo and the brake light, you don't want it to go completely flat and leave you without those.
Remember you can parallel connect 2 batteries to give more capacity, it's just a case of experimentation with the space you have.
Try the biggest you can get in first and see how it copes with the demand, if it's not enough try connecting another in parallel if the space allows.

[davet]

This is what I use in my diablo. I run full DC.



This is how much room I've got left with foam padding in front of battery. I know some struggle to get the battery out so I cut a bit out and fitted a sliding piece.

[Wack]

Nice

[Mel K]

Wack, here's mine also in a Diablo tank , it's an Enduroline YTZ7S, been great, I always trickle charge it . I'm full DC. Oh and it's 6 ah

[Wack]

Thanks

[Train driver]

http://www.ebay.co.uk/itm/09-12-HYOSUNG ... 3641.l6368 These ballistic batteries are the smallest I have found

[Nelly]

http://www.ebay.co.uk/itm/09-12-HYOSUNG-GT250R-Ballistic-Performance-EVO2-4-Cell-Motorcycle-Battery-NEW-/141456020022?_trksid=p2141725.m3641.l6368 These ballistic batteries are the smallest I have found

I'd never seen these before, look like a good bit of kit. Found a you tube video about them.

[Wack]

To alter the original post, I now have a Wassell conversion to do on a Spanish Ser 2 fitted with a TS1.So I've cut the battery tray off and was thinking of fitting a battery the other side as the Jet 200 plastic tank has a large cut out so I could use the Ser2 or a Ser 3 holder but need a battery that would be smaller than standard. What amperage could I get away with? The DC is only going to be powering the lights and horn. Thanks. This is the space I have, the tray will need to be a touch higher to clear petrol tap.A DB4LB battery is just a tad too tall.