Wednesday, November 9, 2011

Lightweight Shorai Battery

Not a vintage project but a cool one. I wanted a new battery for my 2010 Husqvarna TE250, and had recently read about these cool lightweight LiFePO4 (lithium iron phosphate) batteries made by Shorai. I'm a novice in the dirt and I'm short so the idea of lightening the bike a couple pounds sounded like a good idea.

Shorai's "Standard Recommendation" for my bike is the LFX09L2-BS12. There website claims: "This LFX battery is 4.07 Lbs. lighter than the lead-acid YTZ7S." That sounded pretty awesome, and my local dealer had it in stock.
Here is my original battery and the new Shorai.
The new Shorai is significantly shorter and less deep. They provide foam that you can cut to wedge the battery in the battery tray and you can see that in front of the Shorai battery in the picture. They also have these nice bolts with foam underneath that helps raise the nut for fitting the bolt. If you have fit a motorcycle battery before you know this seems like a handy and nice idea.

But what about the weight? First I weighed the original battery.
This is the original battery that came with the bike and including the bolts it weights 4 pounds 8.5 ounces (4.53 pounds).

Now the new Shorai battery.
Wow! 1 pound 4.9 ounces (1.31 pounds), including the bolts and foam shim.

So that is a savings of: 3 pounds 3.6 ounces, or 3.2 pounds. Not really close to Shorai's claim of 4.07 pounds, but still a pretty good weight savings.

Here's a picture of the battery fitted to the bike.

I was careful to zip tie the battery in place, as it definitely cold come loose otherwise, due to it's smaller size. But it does fit really well. (You might notice, I have some extra wiring under my bike for the Power Commander.)

I checked the voltage of the battery when I bought it, and it was at 13.40V. Which Shorai claims means the battery as delivered was at more than 90% charge. I also checked the drain with the ignition off and got 0.17mA on my meter. Thats pretty small, but I think I'll leave the battery disconnected between riding trips.

Cost? The Shorai at $106.62, tax included, was about the same price as a replacement Yuasa MF YTZ-7S battery ($110 online from various sites). But you can get an off-brand sealed AGM YTZ-7S for less than $50. So it's a great deal if you compare to a high end OEM replacement battery, kind of expensive if you compare it to the cheapest batteries out there.

So thats it, probably the easiest 3 pounds I've ever saved on a bike.