Smallest Battery

I am laying out the electrical system of my '72 that has the OE battery box fitted. I am looking for room to mount a Centech AP-1 fuse panel, the Sparx integrated rectifier/VR and 3 micro relays. I need to reduce the size of the battery and I am liking the Yuasa YTZ7S which measures, roughly, 4.5 x 2.75 x 4.1 and has a 130 CCA rating, it is an AGM type. I have the Sparx high output 3 phase alternator so I don't believe that the battery will be needed much beyond starting and idling. I am also wondering if the charging system will be continously over charging such a small battery, leading to a short life and possible melt-down??

For me the width of 2.75 is appealing, but I could go up to 3.0, possibly a tad wider, 8 inches is the wall for length and 7 inches is the wall for height, do any of you have a suggestion for small battery candidates? I intend to run with headlight on at all times and also wonder if a Boyer "Power Box", or similar an option to run without a battery??

RS

Google:
power sonic batteries

Small and cheap.

Vince

I am presently running this battery. I don't have enough time on it to give a good or bad report but it is small and light!

http://cgi.ebay.com/ebaymotors/ws/eBayI ... 0203154498

I've had a Yuasa YTZ7L-BS for a couple years. It seems to be sufficient. I'm running a three phase alternator and always ride with the lights on. I occasionally turn on a KANETSU electric jacket with a heartroller with no problem.
The capacity of the 7 series battery is about 6AH. The biggest hit I've seen is approx negative 8amps on my ammeter idling with the lights on. Before the YTZ7 I had a YTZ5 and it never gave me any problems either.

I've been very happy with a LiFePO battery in my Commando - used a four cell from Maviryk Design (bike is kick only). Smaller than a pack of cigarettes, and not much heavier (under a pound).

Just put one of their 12-cells in a Guzzi Eldorado and that one's working well too. That one weighs 2 pounds and performs at least as well as the 21 pound (I kid you not) lead-acid battery I took out of it.

BrianK said:

I've been very happy with a LiFePO battery in my Commando - used a four cell from Maviryk Design (bike is kick only). Smaller than a pack of cigarettes, and not much heavier (under a pound).

Just put one of their 12-cells in a Guzzi Eldorado and that one's working well too. That one weighs 2 pounds and performs at least as well as the 21 pound (I kid you not) lead-acid battery I took out of it.

Click to expand...

Hello BrianK: Do you run this battery (LiFePo) with any other supporting circuitry?, Can you tell me what the Brand name is, or what website to explore? My Norton will be kick only and it will be fitted with an electronic ignition that is NOT very voltage sensitive.

RS

If you don't mind spending a little more money take a look at the Shorai batteries. They are light, small and very powerful.

I've installed one in my Ducati and it works wonderfully. The Ducati is a very hard bike to start. The Shorai starts mine with no problem.

The battery is so small compared to the Yuasa it replaces, it comes with foam pads of various sizes to 'shim' the battery into the battery box.

If you're going first class this may be a good solution for you. Just make sure the polarity of the terminals matches what you need. If your wiring harness is like mine, it won't matter but you'll want to make sure.

EDIT: Here's a link to Shorai. It should go to the recommended battery for the Commando electric start:

http://www.shoraipower.com/s-55543-Commando-elec-start.aspx

And the battery:

I got along just fine with a 1.2 gel cell sealed alarm type battery I could slip in my back jeans pocket. It could leave bike too low to kick start if I spend ~30 min in stop go traffic and headlight on, but did not stall or balk to barely idle along. It charged up pretty fast once engine could rev into the mid 2000's. Hope to get 2.4 in Li chemistry but may have to assemble my own out of a couple of the cylinder cells. With a 1.2 ah size and Boyer it would not sit and idle 1000 rpm but a few minutes before dropped to ~10.5 v and Boyer went bonkers and stalled. My points bike on tiny battery lasted about double lone 7-8 min. With a good size battery and lights off might idle till Roadster tank ran out.

hobot said:

I got along just fine with a 1.2 gel cell sealed alarm type battery I could slip in my back jeans pocket. It could leave bike too low to kick start if I spend ~30 min in stop go traffic and headlight on, but did not stall or balk to barely idle along. It charged up pretty fast once engine could rev into the mid 2000's. Hope to get 2.4 in Li chemistry but may have to assemble my own out of a couple of the cylinder cells. With a 1.2 ah size and Boyer it would not sit and idle 1000 rpm but a few minutes before dropped to ~10.5 v and Boyer went bonkers and stalled. My points bike on tiny battery lasted about double lone 7-8 min. With a good size battery and lights off might idle till Roadster tank ran out.

Click to expand...

So Steve,

Brilliant! By locating the battery in your back pocket, the bike obviously shut down immediately upon your dismounting. Kind of a kill switch huh?

Actually no Steve, both my bikes, one points and one Boyer will run just fine after flinging the battery out of the side cover. Will kick start points pretty easy but Boyer usually needs 20 mph roll off. At my first rally, I goofed on Boyer trigger wire upgrade and worm battery and me down all day lone and most the night. Next day walked battery to charger in back pocket, to surprise the guys waiting for me, empty handed.

Butt maybe you are on to something, I wouldn't have a behind w/o my wallet and pocket knife.

RoadScholar said:

BrianK said:

I've been very happy with a LiFePO battery in my Commando - used a four cell from Maviryk Design (bike is kick only). Smaller than a pack of cigarettes, and not much heavier (under a pound).

Just put one of their 12-cells in a Guzzi Eldorado and that one's working well too. That one weighs 2 pounds and performs at least as well as the 21 pound (I kid you not) lead-acid battery I took out of it.

Click to expand...

Hello BrianK: Do you run this battery (LiFePo) with any other supporting circuitry?, Can you tell me what the Brand name is, or what website to explore? My Norton will be kick only and it will be fitted with an electronic ignition that is NOT very voltage sensitive.

RS

Click to expand...

Hi Bill. You can find the ones I use at http://www.mavirykdesign.com. They're basically the same innards as Shorai, Speedcell, etc. (123 cells, I think they call them - see the website), assembled by a smaller company (Jim Ong, who was a grad student in EE when I bought my first battery from him - seems like a great guy and the products are terrific, plus I like supporting a young entrepreneur instead of a big corporation). I put mine into my bike without modifications. I run a Boyer EI, Sparx 3-phase alternator (with voltage regulator, no zener), Dyna coils, and a fairly recent new wiring harness with most connections cut and soldered instead of using connectors. (The only Lucas bits still on the bike are the handlebar switches and the taillight assembly.)

Not sure if I've answered your questions so reply or email/PM if others.

Out of curiosity plus the desire to learn from your expertise, what EI are you going to run? - BK

speaking about bacteries, I was looking for a bactery charger for my norton:
would you suggest the optimate or the much cheaper Battery Tender junior? what is your experience?

**********Out of curiosity plus the desire to learn from your expertise, what EI are you going to run?**********

I purchased a Tri-Spark before I purchased Rocky Point Cycle. I sell Boyers (which come with a 5 year no BS warranty) so I am quite torn. I think I'll use the Tri-Spark in Norton I'm almost finished with and use a Boyer in the R90S that I have under construction, then just stick with the Boyers.

RS

Lorenzo said:

speaking about bacteries, I was looking for a bactery charger for my norton:
would you suggest the optimate or the much cheaper Battery Tender junior? what is your experience?

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I recommend the less expensive Battery Tender Junior. I have 6 bikes plugged in at my shop and have pulled a few after 2-3 months of sitting and they cranked to beat the band. I have used them for the last 3 years and they run continously for 3-4 months a year so they have demonstrated good reliability.

RS

Concur with Scholar. I've used the Tenders for years now and find that they work perfectly. They also use a connector that's commonly found in any autoparts place. Makes it easy to attach a pigtail to more than one bike and rotate the charger.