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Discussion Starter · #1 ·
I was thinking of replacing the battery to save weight, I was reluctant to use a lithium battery due to safety concerns but have since found that LifePO4 batteries are available and much safer, while still lightweight.

I have read good things about Shorai batteries, I found that the original is HTZ12A-BS which is equivalent to YT12A-BS, so was thinking to go for this one which is the closest I could find:


Does anyone have any thoughts of possible reasons not to go for the swap? Anyone using lithium batteries in their dukes?

Thanks
 

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I too have the Anti Gravity ATZ-10 battery and have NO issues or problems. Plus it gave the bike 1 more horsepower!
6 pounds weight loss = 1 horsepower.
 

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I've had a Shorai in my 640 Adventure for 10 years and it is still going strong. Saved about 3 kg weight, got faster cranking but the caveat is they don't have the reserve capacity of the lead acid types. Also had one in my VFR for a while, and an 1190 Adventure.

You will want an LFX14 minimum, or preferably 18 or 19 though. The latter is Shorai's recommendation. LFX12 has a fairly low rating at 155 CCA. Initially the 14 was specced for my 640 to replace a YTZ10S but they've since bumped that up to the 18.
 

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Does anyone have any thoughts of possible reasons not to go for the swap? Anyone using lithium batteries in their dukes?

Thanks

This is a bit of a geeky response. But I would NOT fit a LiFePO4 to my 790D.
 

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Discussion Starter · #7 ·
I've had a Shorai in my 640 Adventure for 10 years and it is still going strong. Saved about 3 kg weight, got faster cranking but the caveat is they don't have the reserve capacity of the lead acid types. Also had one in my VFR for a while, and an 1190 Adventure.

You will want an LFX14 minimum, or preferably 18 or 19 though. The latter is Shorai's recommendation. LFX12 has a fairly low rating at 155 CCA. Initially the 14 was specced for my 640 to replace a YTZ10S but they've since bumped that up to the 18.
One thing I don't understand is why they have 2 different numbers for storage capacity and equivalent storage capacity:

  • Storage Capacity: 4.95Ah
  • Lead/Acid equivalent capacity: 14Ah
  • Cold-start performance: 210A CCA

The 14 seems over-specced compared to stock? Why would you want the bigger one?

Thanks
 

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One thing I don't understand is why they have 2 different numbers for storage capacity and equivalent storage capacity:

  • Storage Capacity: 4.95Ah
  • Lead/Acid equivalent capacity: 14Ah
  • Cold-start performance: 210A CCA

The 14 seems over-specced compared to stock? Why would you want the bigger one?

Thanks
It's do with how they get the numbers. Some are "real" and some are a point on a line generated using a test designed to compare a single type of technology. The tests aren't so useful to compare the performance of different technologies, hence the "equivalant" wording, and the point reference doesn't tell you anything about the shape of the curve.

The 14 was the initial recommendation from Shorai for a few bikes, but they didn't have the 18 in the shorter A4 size case back then. Presumably real-world feedback resulted in the change to the 18 as the recommendation, and then they released the 19A4 to increase the storage capacity in the shorter A4 case as well.

You could possibly get away with the 14, and since I now have one spare I'm going to try it. But if I was buying I'd get the bigger one for peace of mind. Alternatively, get a portable starting battery thingy. Something that isn't mentioned very often is that this technology is rated several times more deep cycle events (5000 vs 1500, or something like that) vs lead acid, so they last a lot longer - which makes them also a value proposition.
 

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This is a bit of a geeky response. But I would NOT fit a LiFePO4 to my 790D.
I have read all that and the only thing I got from it was "don't let your battery run down if you have an immobilizer". Nothing against a LiFePO4 per se.
 

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I put a shorai into a KTM 990 SMT. It left me stranded at work in 20 degree (-7c) weather. No matter what "warm up" I tried, it wouldn't crank over. So they suck in cold soak situations. If it's always warm, then go for it. After taking a bus home with all my riding gear, hitching up a trailer, rescuing my bike in the dark, swapping battery to a new lead acid, I'll never do one again.
 

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I have read all that and the only thing I got from it was "don't let your battery run down if you have an immobilizer". Nothing against a LiFePO4 per se.
I have both.

The real world issue is that if a Lithium goes into "sleep mode" due to the chill overnight, you have to make it work to get the chemistry started. And the OP is from the UK.

The obvious way to warm up teh chemistry is whack the lights on - but on the 790 (AFAIK) they don't come on unless the engine runs.
And from my experience even in early summer in Dorset (UK) they can go dormant - inside a lockup style garage.

Here in Spain we get less chilly days - but even so.

The choice of Cells matters hugely. A123Sysyems Nanophosphate cells ime - WAY less prone to going sleepy.
I stand by - Stick a YUASA lead Acid in. And carry a booster pack in the jacket (or leave it inside the house)

This LiFePO4 "wakes" very fast,
Light Fluid Circuit component Gas Cylinder


560 pulse Amp discharge at 13.2V - but has no regulation - and it's big brother

Hood Motor vehicle Electrical wiring Automotive exterior Gas


smoked a Car starter motor - 1120Amps at 13.2V
 

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This I understand - How much weight will it actually save? - I haven't looked.
Around 2.0 kg. That's a fair bit on this bike.

Silencer 1 kg
Pillion pegs delete and single seat cover 3 kg
Lithium battery 2 kg
Motomaster front discs 3 kg

169 kg is now 160 kg. A useful change without spending a lot of cash. (There's another 6 kg in the full exhaust system if you have 3500 Euros or so to spend including programmable ECU, and your ears can stand it. A few more ponies, too.)
 

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Discussion Starter · #18 ·
imho dodgy as it says lifepo4 on the box and then li-ion on the battery, also doesn't looik like they honour the warranty, see comment at the bottom here
 

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Discussion Starter · #19 ·
I've had a Shorai in my 640 Adventure for 10 years and it is still going strong. Saved about 3 kg weight, got faster cranking but the caveat is they don't have the reserve capacity of the lead acid types. Also had one in my VFR for a while, and an 1190 Adventure.

You will want an LFX14 minimum, or preferably 18 or 19 though. The latter is Shorai's recommendation. LFX12 has a fairly low rating at 155 CCA. Initially the 14 was specced for my 640 to replace a YTZ10S but they've since bumped that up to the 18.
I see, well it would come down to £200 battery + £80 charger, too expensive
 

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imho dodgy as it says lifepo4 on the box and then li-ion on the battery, also doesn't looik like they honour the warranty, see comment at the bottom here
OK - What do you think ion means? - It (ion) is a generic term and there are LOTS AND LOTS of ions. in lithium battery terms, Iron-Phosphate is one of them.
If it says LiFePO4 anywhere and isn't - you can shut the buggers down in a week.

I deliberately cut this from Wikipedia

Chemistry, performance, cost and safety characteristics vary across types of lithium-ion batteries. Handheld electronics mostly use lithium polymer batteries (with a polymer gel as electrolyte), a lithium cobalt oxide (LiCoO2) cathode material, and a graphite anode, which together offer a high energy density.[17][18] Lithium iron phosphate (LiFePO4), lithium manganese oxide (LiMn2O4spinel, or Li2MnO3-based lithium rich layered materials, LMR-NMC), and lithium nickel manganese cobalt oxide (LiNiMnCoO2 or NMC) may offer longer lives and may have better rate capability.

And Yes! - I did know - it was just easier to copy/paste.
 
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