KTM 790 Duke Forum banner
21 - 40 of 44 Posts

·
Registered
Joined
·
2,538 Posts
Around 2.0 kg. That's a fair bit on this bike.
About 2.6litres of fuel. Or couple of pints, steak'n'chips and a pudding.
Yes I am just chain yanking. But at my delicious 85 kg "au naturel" - 9 here or there suddenly becomes rather insignificant.
Helmet/leathers/boots etc - 10Kg? Just jawing.
 

·
Registered
Joined
·
64 Posts
Discussion Starter · #23 ·
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.
yep apologies, I realised that lifepo4 and li-ion are not mutually exclusive after posting that

Imagine you drop your bike - after a couple of pints - and there nobody there to help you out ... what if your bike is just 2 kg too heavy for you to lift it up by yourself ?
:p :censored:
it's true it could mean the difference between life and death! lolz

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.)
isn't the stock battery 3.8kg? Should be close to 3kg less
Weight: 3.8Kg
 

·
Registered
Joined
·
131 Posts
isn't the stock battery 3.8kg? Should be close to 3kg less
Weight: 3.8Kg
The slightly undersized Motobatt in mine only weighed 2.9 kg.

The nearest to the OEM Haijiu I can find says 3.6 kg, so that’s 2.7 kg saved. Do they use Yuasa elsewhere?

Less weight always makes your life easier. Except in crosswinds! LOL
 

·
Registered
Joined
·
131 Posts
How's that possible? The yuasa equivalent to the stock one here is only £59?
Not for the Duke, but my 640 a long time ago. Only the Shorai prices have doubled - supply and demand.

Currently that Yuasa YTZ10S is £155. A fair premium over the Duke fitment. It was by far the most expensive battery in the range. Very high output in a small case, and there’s no room to fit a bigger one unless you relocate some stuff.
YTZ10S
 

·
Registered
Joined
·
2,538 Posts
Just off tack-ing. Just seen a really good article about SODIUM-ION batteries. CATL (a HUGE battery maker - reputedly world's biggest) is already pushing past LiFePO4 energy storage levels. And it's cheaper and more sustainable. I'm off to look for cells.
 

·
Registered
Joined
·
34 Posts
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
Go up one size if available. In the past, Shorai got carried away with small. I did not have enough cold temp reserve as a result. I replaced with one size larger and less difficulty with cold temp starting. The Duke does not tolerate liw voltage at starting, as it will go into fault mode. Keep it charged with Shorai charger.
 

·
Registered
Joined
·
64 Posts
Discussion Starter · #32 ·
Go up one size if available. In the past, Shorai got carried away with small. I did not have enough cold temp reserve as a result. I replaced with one size larger and less difficulty with cold temp starting. The Duke does not tolerate liw voltage at starting, as it will go into fault mode. Keep it charged with Shorai charger.
The bike is not in a garage with access to power, is this a problem with these batteries? I thought they'd hold the carge much better than lead acid.
 

·
Registered
Joined
·
2,538 Posts
I thought they'd hold the carge much better than lead acid.
They hold LESS overall energy because they have LESS overall capacity.
If you have ANYTHING like an alarm fitted - just don't even try.

It all depends how often you warm up the internal chemistry.

I have a LiFePO4 Battery on my big Triumph. It's fine here in Spain. OK I may need to insist a bit after being stood a month in winter.
But on trips to the UK (Dorset) - just leaving it in my mum's unheated and damp garage overnight in late spring and the battery has to be warmed up to get the chemistry working. This I can do as the lighting works independent of the engine running or not.

When the KTM's battery dies (they all do eventually) I will NOT Be fitting a lithium unit. A good (YUASA) Lead-Acid is a better allround solution.

If I were to do so however - I would contact a bespoke LiFePO4 specialist - give them the dimensions of the "hole" the battery fits in and ask them to make the biggest one possible for the space.
 

·
Registered
Joined
·
131 Posts
The bike is not in a garage with access to power, is this a problem with these batteries? I thought they'd hold the carge much better than lead acid.
Their self-discharge is much lower, yes.

Disconnect it (ground lead) from the bike if you’re not going to ride it for a while.
 

·
Registered
Joined
·
131 Posts
If I were to do so however - I would contact a bespoke LiFePO4 specialist - give them the dimensions of the "hole" the battery fits in and ask them to make the biggest one possible for the space.
Seems overkill. The Shorai LFX19 as an upgrade from the 14 and then 18 in the same case is likely as power dense as practical - otherwise they’d have gone 20 or more.

Definitely gotta watch the parasitic and standby drain on the things though.
 

·
Registered
Joined
·
2,538 Posts
The Shorai LFX19 is a 19aH LEAD ACID EQUIVALENT.
I cannot see the TRUE values. At a guess likely 7.8aH. Just based on the discharge amps.
Yeah - I am geeky and uncompromising - but I've first hand experience of the cell/pouch differences.

Overall Li batteries do not like temps below 5ºC for true cold starts. They get temperamental below 10ºC - ime.
So for @shmod in the UK and no garage with power - I'd not risk it.
 

·
Registered
Joined
·
126 Posts
I had a Shorai LFX21L6 on my HD some years ago.
Honestly, I don't remember having had any problem starting the bike in cold weather ; may have been lucky with this particular battery (not below 0°C temperature though !).
However, I do remember Shorai advising their custumers to let some current flow for 10-30 sec when starting at 5°C down to -7°C ... and for a few minutes when down to -17°C !
 

·
Registered
Joined
·
2,538 Posts
However, I do remember Shorai advising their custumers to let some current flow for 10-30 sec when starting at 5°C down to -7°C ... and for a few minutes when down to -17°C !
The issue on anything modern where there is little to no power draw without first starting makes this awkward. The old trick was put the lights on - But not on a 790D.
 

·
a d m i n .
Joined
·
151,039 Posts
My Honda CBR SP comes standard wt a lithium battery. Zero issues, and I’ve yet to purchase a maintainer for the winter. I don’t ride when it’s cold, so no starting issues, (it has to be over 50º F (10ºC), in order for me to want to ride, haa).
 

·
Registered
Joined
·
64 Posts
Discussion Starter · #40 ·
I think I might pull the trigger on one of these..


CCA is 360, think it might be overkill? I'd be happy to get a smaller one. This one has the same exact dimensions of the stock one I believe.
 
21 - 40 of 44 Posts
Top