Extra battery

Use a battery that does not vent such as a gel cell. You do not want a regular battery venting into an enclosed area.
We often will use 2 6 volt gel cells on thier side mounted under the sidecar body. This way we do not loose trunk space.
Jay Giese
Dauntless Motors Corporation
www.dauntlessmotors.com

A few years back, I ran an automotive/marine type battery in a marine box in my Panhead/Ural rig. The battery was very inexpensive but it was designed for use in an enclosed area and it had a vent tube like the motorcycle batteries have. I just poked the vent tube down out of the trunk through a grommet in an existing drain hole in the floor. I don't remember the MFG of the battery, but it was designed for use in an enclosed area and it had both bolt and post type terminals. Good ballast, cheap, and it never wore down.
As Jay mentioned in his post: Don't install a wet cell battery in an enclosed space. As they discharge, Hydrogen gas is formed and it is very volatile. (Read that Explosive).

Thanks for the info, I'm thinking about the Optima battery. Gel cell 12volt, weighs about sixty pounds(good ballast). What do you think about using an automotive fuse block to distribute the power to the various accessories?

We have run automotive batteries for years in our sidecar rigs but always got rid of the motorcycle battery completely. They work great and the reserve power is excellent. They cost less typically and last what seems forever.
Trying to run the two batteries (motorcycle and car...not what Jay was speaking of) can create problems if not set up properly and it is just not worth the hassle.
Never have used an Optima but am considering it. They are a little costly but the feedback we have received has been excellent. Look on their website as there are different features offered.

Accessory fuse blocks are nice as long as they are wired with the proper guage stock. I have always just plugged into the original ground and positive battery lead positions on the bike, using generous sized leads from the battery. The discharge amperage draw of your bikes existing accessories is already covered with a proper fuse or circuit breaker. An accessory fuse block could cover added items like heaters and noise makers and extra visuals nicely without disturbing the existing system.

It may be a good idea to put a fuse or circuit breaker on the positive lead to the battery that matches the rated max. output of your alternator.

A flat car battery can pull more amps than your alternator is designed to deliver, after all, it is much larger than a motorcycle battery. The alternator can toast itself trying to charge a big dead battery.

Dave

Dnepr MT-16, 14 amp alternator

I was down at Sears today and saw that they sell the optima batteries. However the $126 price (with exchange) for the "red top" did tend to cool my enthusiasm a bit. While looking around at other options, I came across a "wheelchair" battery. This is a deep cycle gell cell for around $35. It puts out a little over 200 cold crank amps. Now it seem time to get out my tape measure and see how to stuff them in my wheeled chair.

I like the idea of the larger battery, but have two questions. Someone mentioned about the stock charging system keeping up. I have a Moto Guzzi Cal II with a 20 amp charge system (stock) if the battery is maintained well ie. battery tender during downtimes will this keep up with the bigger battery? Also I would remove the stock battery under the seat. How do I connect now? I was thinking of mounting a "junction" at that location and hooking cables from sidecar directly to those now attached to my present battery. Is this the right way? Thanks in advance. BillinPA

Plugging in to existing or with a junction block works for me.

Hack'n, are you saying leave my present battery and attach the cables from new battery to old battery, leaving existing cables in place? I think that is what you are saying, I just did not realize that was an option. BillinPA

Bill,
'Keeping up' with the large battery is typically not the issue. You will only be recharging what you have used. If you do need to charge it for some reason you can charge a car battery quickly on a charger.
On our present rig we have run electric vests, extra lights plus 2 Hella driving lights and have still never had to do an extra charge other than what the bike does.The bike is a '79 XS1100 Yamaha.I don;t know the charging capicity that it has but I bet it isn't near what the newer bikes are.
Note that We have always took out the stock battery and just run the car battery.

Your alternaor being able to keep up is not a problem, unless your equipment draws more amps than your alternator puts out. The big problem occurs when you have a dead battery, if you have a small capacity alternator, the alternator will toast itself, trying to charge that big car battery. A fuse or a circuit breaker, to the battery, is cheap insurance.

Dave

Bill,

I don't reccommend doing that. I tried using two batteries wired in parallel. It would probably work better if both batteries were identical and in the same point in their life cycle. When you put in two batteries of different sizes, it seems that one is always trying to charge the other. Anyway, it was problematic.

What worked for me was to set up a pair of dummy battery terminal substitutes in the approximate position of the old battery and run BIG wire [#6 is what I used] from the battery in the hack to the ersatz "battery placeholder" in the bike. To make my battery placeholder, I used plexiglass and a couple of nice stainless bolts sized to match the old battery connectors, then I attached a shortish pigtail with a heavy duty connector that was used to charge forklift trucks.[ http://www.andersonpower.com/products/mp/sb.html ] The connectors are available from a bunch of places and they are used for all sorts of things but I got mine from a forklift supply place. By adding the connector, I can easily disconnect the battery without actually loosening any fasteners. The whole thing has worked just fine for three years now [since I got rid of the second battery]

Thanks Guys for the help, I just replaced the battery last week, so I am unsure when I may do this. I had never looked into it, but it seems like a good idea. Now I am able to make a plan if I pursue it. Thanks again. BillinPA