Mk3 Battery upgrade - Shorai LFX21A6-BS12

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I was planning to upgrade the battery in a bone stock MK3 with a Shorai LFX21A6-BS12.
Will the stock alternator and stock voltage components work well with this battery?
Should I plan on other modern components to go along with this Shorai?

Anyone running this Shorai in an Mk3?

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this looks like stock battery


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I use a battery from Batteries plus. It's a AGM battery, 14AHL-BS, Sold under the Duracell brand name, Made by the East Pen Co.
Runs the electric starter with no issues. The last one went 6 years.
 
I am not comfortable recommending a lithium ion or lithium polymer battery to anyone that has the standard charging system on a bike, or even a podtronics type of regulator/rectifier.

For me, I like to see a minimum spec of a series type regulator/rectifier as used on a modern bike before you use a lithium-based battery. Exactly what we’ve fitted to the MK3

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Just look at phones and tablets exploding on planes. The massive recall of the Samsung devices in 2017, the freak fires where kids leave devices charging on their beds.

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Then look at the electric cars catching fire.
And all this modern kit has special chargers designed for the job in hand!!!!

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Now consider you have the same type of battery being charged by a very antiquated charging system, above a red hot engine that shakes and rattles (even with isolastics) and you are sat astride a tank full of petrol.

I just don’t like the idea.


The original selenium rectifier and zener diode output your excess charge as heat when your battery is fully charged, but there is no ‘logic’ that is checking that charge rate or the over charging.

A podtronics is similar, but worse, the circuitry keeps your alternator under 100% load 100% of the time. One of the reasons we are seeing more alternator failures.

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These are $3 components encapsulated in resin on the underside of a large heatsink.

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At least the branded Podtronics units are wired up correctly, potted with resin that actually transfers heat, and use wires that are thick enough to carry the current.

The cheaper $20 units may look the same but they are not assembled with the same care.


So I guess my answer is yes, I recommend you plan to install some other modern components alongside your Shorai

Shorai is not concerned with the charging systems on motorcycles as long as the charging system doesn't exceed 15V. They are concerned about regular chargers overcharging, hence their stipulation not to use a regular battery charger on their battery-according to their literature. I think the Podtronics regulates the charge better than the zener. I have seen the series style regulator but as I haven't had any issues with my other bikes I will continue with the Podtronics-However as per your posts I will keep an eye on my electrical bits.
 
@Fast Eddie great summary Nigel!

The Harley boys are starting to light up to the benefits of series type units now, so there are a few more coming into the market. Most of these are big, blingy and shiny though.

I like the Shindengen units, as they are quiet, unassuming and come in the same package as mosfet and shunt type reg/recs that we are all familiar with.

They are trying to phase out the SH775 in favour of their latest models.
I think they see the SH847 as the replacement, as it’s been tweaked to better handle a wider (and much higher) rev range.

The pic in my post above is the SH775.
We recently moved it so we can get an original style air filter in.

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I use the SH775 RR unit on a 36 Yo Yamaha. It had a shunt style RR and cooked a couple of stators before I figured out why. The SH775 RR I have came from a CanAm, same as is used on a late Triumph. Get the Triumph pig tail and it's plug and play if you have a 3 phase charging system.
 
p400
I have used the Shorai LFX21A6-BS12 on my E Start only Mk3 for the last five years and agree with other lithium users positive experiences posted here.
An electrical fire can quite easily be caused by faulty wiring or component failure regardless of what battery type is installed.

This Shorai is an excellent if pricey upgrade, 7.5lbs lighter than the Yuasa YTX16-BS used previously and stays charged far longer.
The only downside I,ve found on my daily work ride over winter, is the warm up period needed to wake the battery in low to sub zero cold start mornings (+3c to -2c early December 2018) Shorai advise leaving the headlight on full for a few minutes but I reinstalled my old Yuasa for convenience.
With warmer temps I,ve refitted the Shorai as it definitely has more cranking power on e start and higher capacity for touring duties like phone, camera and ipad charging, music etc.

No special voltage reg rec, other fancy parts or negative earth conversions required, standard components in good condition work fine.
I use a Lucas RM24 47244 3 Phase alternator with Lucas TPR200 Reg Rectifier (or 3 phase Sparx before that, now carried as a backup) Resting voltage is lower than max 14.4v at around 13.5v but has worked perfectly on stop-start around town or on long runs, always with the lights on incl. the High Output Osram H4 and soon to be fitted electric grips. Ignition is Trispark Classic.
An analog voltmeter keeps tabs on voltage and just confirms all working well.

My old Optimate 3 tops up the battery if necessary and the dedicated and expensive Shorai charger has not been needed.
I fitted it across the frame and made a carbon case that will house either battery using the Shorai foam shims in the box. I would say go for it, a great mod and like the (much smaller) Shorai on my FJ1200, it,s outlasted all my Yuasas.
 
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I use earth x lithium batteries in my bmw and mk3 and they provide plenty of power, are very compact and has an actual weight of 2.2 lbs .. (I weighed it) .... You can use a regular charger on it and it has a overload protector in it.
 
I run a two wire alternator and a Shorai battery ( kickstart only) with a SH775 from polaris. It charged just fine running down the road at 14.1 v with a powerarc ignition. Since I have switched to a Pazon I only get 13.3 v. I am going to have to go back to a AGM battery.
 
....Just look at phones and tablets exploding on planes. The massive recall of the Samsung devices in 2017, the freak fires where kids leave devices charging on their beds.

Then look at the electric cars catching fire.
And all this modern kit has special chargers designed for the job in hand!!!!.................


All the examples you mention have different battery chemistries than the Shorai batteries. Most, if not all motorcycle and car replacement Li batteries are of the lithium iron phosphate (LiFePO4) type. This chemistry is chemically and thermally stable and is not prone to thermal runaway, like other Lithium battery chemistries.

My Commando has a CNW starter kit, a high output alternator, and a Battery Tender brand LiFePO4 battery. It has always started right up.

Incidentally, LiFePO4 batteries like to be warmed up before being tasked with cranking an engine in cold weather. If the weather is very cold it's best to turn on the headlight for a few seconds before starting the engine. It is somewhat counterintuitive, but it works.
 
@C317414 as I say in my post, it’s just my opinion based on my own experience and testing.

Here are some examples of LiPo batteries catching fire.

Mk3 Battery upgrade - Shorai LFX21A6-BS12 Mk3 Battery upgrade - Shorai LFX21A6-BS12 Mk3 Battery upgrade - Shorai LFX21A6-BS12 Mk3 Battery upgrade - Shorai LFX21A6-BS12 Mk3 Battery upgrade - Shorai LFX21A6-BS12

Of course you can do whatever you like - that’s the great thing about this world, but I do think it’s important that people are aware that it’s not a drop in replacement for older bikes like the manufacturer says it is.
 
I've seen a number of lead acid batteries that exploded, so I believe it could happen with any battery. In any case, I am comfortable enough with LiFePO4 batteries that I'm contemplating using them for house batteries on my boat.
 
Interesting thread in that it sent me to research "lithium" batteries. I had no idea there were more than 20 different Lithium + other element battery combinations! https://en.wikipedia.org/wiki/Lithium_battery

Unlike most of the other Lithium + (whatever) batteries, Lithium Iron batteries - like the Shorai - are considered suitable for replacing lead acid batteries in vehicles. Here's a quote from a Wikipedia article: "Because of the nominal 3.2 V output, four cells can be placed in series for a nominal voltage of 12.8 V. This comes close to the nominal voltage of six-cell lead-acid batteries. Along with the good safety characteristics of LFP [Lithium-Iron] batteries, this makes LFP a good potential replacement for lead-acid batteries in applications such as automotive and solar applications, provided the charging systems are adapted not to damage the LFP cells through excessive charging voltages (beyond 3.6 volts DC per cell while under charge)" The entire article is here: https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery

For ten years (until this thread) I had thought that Shorai calling their battery "Lithium Iron" as opposed to "Lithium ion" or just "Lithium" was just some sort of catchphrase or marketing speak but "Lithium Iron" is just one type of the more than 20 different kinds of "lithium" batteries.
 
I'm with gtiller on this, and like him it's just my personal choice from my personal experience to date.
In my64 years Ive purchased and used long term probably 100 or so wet lead acid batteries for various cars,trucks, motorcycles, crawler tractors and farm tractors. Like most people I have probably ridden in more than a thousand vehicles that utilized lead acid batteries.
In all of that experience Ive never seen a single lead acid battery catch fire or melt.
The batteries I've purchased have probably averaged five or six years longevity, the car batteries much more, some lasting 12 years or so.

I've had two LiFePO4 batteries.
One melted and took out the charging system at 18 months, the other just died at 14 months.

Glen
 
The original selenium rectifier

That was a generation before the Lucas 2DS506 rectifier which is a silicon device.Selenium rectifiers were used from the early 1930's and were not used inconjunction with the Lucas zener diode,also a silicon based diode.Selenium rectifiers are not as efficient as silicon based diode rectifiers.
 
I'm with gtiller on this

You sure Glen...? gtiller has a Shorai battery on his mk3...

If I’m understanding his posts correctly, he is making a case for use of correct components to control the charging circuit properly... and pointing out what can happen if you don’t, especially if using a lithium battery.
 
@Fast Eddie correct - from my research, I determined Shorai is the best of the bunch:
- high cold cranking amps
- very light weight
- stable materials vs some of the other more extravagant materials used where the jury is still out.


However, I have their special charger, and have significantly modded the charge circuit of the bike to accommodate it along with a general electrical refresh.

Removed:
- lead acid battery
- two zeners
- rectifier
- assimilator
- points
- two 6 volt coils
- capacitor
- two condensers
- ballast resistor

New:
- shorai (36Ah 540CCA)
- shindengen SH775
- lucas RM24 LU47244 175 watt 3 phase alternator stator
- lucas RM20 LU54202299 rotor - turned down to provide correct clearance
- twin output single coil
- tri-spark electronic ignition
- 4 brush/4 coil starter (used a new harley prestolite as a parts donor)
- heavier gauge cables
- modified anti backfire device to take the extra torque
- charge warning light from www.improvingclassicmotorcycles.com
- fused main harness AND separately fused charge circuit


With this kind of setup, and peace of mind, I can highly recommend Shorai.
 
I have (almost) the same set up Grant, without all that heavy electric leg nonesense ;)

When you say ‘fused charge circuit’ do you mean fuses between the alternator and Shindengen unit? Or betweeen the Shindengen unit and the battery?
 
@Fast Eddie the reg/rec is wired directly to the +ve and -ve terminals of the battery via it's own fuse.

The logic behind that is if there is charging issue:
1) the charging circuit fuse will blow, protecting the battery
2) maybe this will give you a chance of getting home, as the coil will still be getting power
 
On a non-electric starting Commando, an old style lead/acid battery will be ok, and worked well for the last 40 odd years on my bikes, and I suspect that exotic li-ion batteries are imo a solution in search of a problem.

However what I read above about the Podtronics regulators was something I was unaware of : The fact that these regulators kept the alternator on full load all the time. Should I be worried now? I installed a podtronics regulator on the Commando about a year ago, works well so far, although I have to admit that I did not put many miles on it after installation of this unit. would replacement with a Shindingen unit be a safer option ?
 
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