'07 BMW G650 XCountry
Mod: New technology LiFePO4 battery from Sycl:
The object here is to find a reliable battery to crank the motor over (as opposed to a lot of Ah (Amp Hours) for running accessories, which lithium batteries are not as good for).
You can read all the details about the comparison between traditional lead AGM types vs. the new LiFePO4 (Lithium Iron Phosphate) on my G650 XCountry Links page (search for: "Battery:").
But this page is just a summary:
The choices that I believe will fit are:
- AGM (lead) type: Yuasa YTZ10S or Odyssey PC310.
- LiFePO4 type: The EarthX ETX18B monster one fits.
Or the Shorai LFX14A2-BS12 or maybe their taller LFX18A1-BS12 is not too tall to fit?
Or Testsycl.com may still sell their Sycl branded 8-cell 4.6 AH.
Or the Ballistic 8 cell or the monster 12 cell are the same height and are tight but they have been made to fit by cutting off the top plastic pieces.
- I chose the Sycl 4.6AH (8-cell) battery. One reason is I decided to try the LiFePO4 over lead acid mainly to just try it and see how it feels having more cranking amps the more you crank. Sure it is smaller and lighter but to me I only care about cranking amps dependably. The only drawback I felt was the cold weather warmup first issues. I was not confident in the Shorai only due to some G650X riders having massive cold start delays, yet I know the Sycl 8-cell has been used tbarstow without any real cold start problems (1-2 minutes at 32 degrees F perhaps).
- I also believe the 3.3v cell made by A123 systems has been proven in many other electric vehicle applications and the Shorai may not have as much history yet. I would have chosen the Ballistic but I think it is clearly too tall to fit.
- I also really like the quick disconnect connectors on the Sycl and the low hassle backup of the 2.3AH (4 cell) as a backup which I could carry as a spare on some adventures, especially since I have a Rekluse semi-auto clutch installed so I cannot bump start it.
(UPDATE: If I was to do it again, I would get the monster EarthX ETX18B.)
Here is a visual comparison between the Yuasa YTZ10S and the Sycl 8 cell:
I forgot to take a picture of the mounting before I stuffed all the battery cables into the box, but I used the included velcro on the bottom, and 3 zip ties to hold it in, similar to this picture copied from tbarstow's install:
Here is my install, with the long-ish battery leads stuffed inside the battery box:
I also bought the smaller Sycl 4 cell (2.3AH) to carry as a spare on some adventurous trips. My plan is to pull out the cables and shove it into the battery box with the bubble pack to make it snug, then shove the battery cables in above the batteries. It will all easily fit. You must first unplug the (dead) 8 cell battery or it will cause too big a load for the little 4 cell. But I have tried it and the 4 cell cranks it just fine.
Update: Cold weather cranking results:
I got it in December so tried out it's cold weather starting performance and this is what I found:
- At 40 degrees F there was no delay in starting.
- At 20 degrees F for 2 hours it took about a minute to warmup with the headlight first before it would crank enough to start it.
- At 20 degrees F overnight soak (with frost all over the bike) it took a total of about 10 minutes, mostly with the key and headlight on for 1 minute then off for 30 seconds before cranking. There may be a better way like don't turn off the key at all, I don't know but I got that idea from the Shorai instructions.
This new LiFePO4 technology takes getting used to after being so used to lead based batteries, as at first after cranking it awhile it sounded "dead" and was too low a voltage and it reset the entire display and in fact it went blank and cleared all the trip miles.
But sure enough the more I left the light on and got the chemistry going, the more cranking amps it would put out!
I also tried my backup 4 cell Sycl and it was able to start my bike at 40 degrees F with no problem or delay.