More charging info

The other thread melted down from high voltage without ever answering the basic question-
Are any of the Lucas or Lucas type alternators suitable for running Lithium batteries in our old Nortons?
I thought it best to go right to the horse , Shorai.
I used numbers for my RM23 since I have those. A high output 3 phase RM24 is stronger at low rpm, but I have not been able to find voltage data for it. My guess from the original Lucas chart is that the RM24 hits 13.1 v at about 2800 rpm.

My question to Shorai-

" I would like to use a Shorai battery in my 1975 Norton Commando MK3.
The idle charging output is below the 13.1 called for by Shorai. Idle (1000 rpm) voltage output of the alternator is around 8 volts. At approximately 3500 rpm it reaches 13.1 v, according to testing done with a 100watt load.
If I maintain the battery voltage above the minimum 12.86 v by avoiding prolonged idling, will the Shorai LFX18 work well in the Norton?


Shorai' answer

Hi Glenn,



I wouldn’t recommend it. You would be discharging the battery when idling, and at 13.1V you would barely be charging the battery.



Ideally you would want to see about 13.3V at idle, and max 14.2V at higher RPM. 13.3-138V is pretty normal for a modern bike with a regulator, but I know your bike is not modern



If you want to run ANY lithium battery, it would be good to see the ranges mentioned above.



If you don’t want to swap system with a regulator, then best would be to stick with lead-acid / gel batteries. They can tolerate the voltage swings, from the stock alternator.

I read the same thing before buying a Shorai battery. I have a digital voltmeter fitted to my bike.

I think that Shorai is correct in their assessment, but one thing that is missing is the current draw at idle. Modern bikes with their fuel injection and sophisticated electrical systems draw a lot of power at all times running.

My Norton only draws about 3.8 amps idling with the headlight on. Yes, idling for long periods of time will draw down the battery, but I can sit at a stoplight (about the most time typically I spend sitting idle) and my voltage will stay above 13.3. Sure, I am not charging the battery, but as soon as I am moving again, the voltage is soon up to 14.4 again. The documentation that came with my battery stated that 14.8 volts was a not to exceed value.

The odd time I am idling for longer, I flip the headlight over to the pilot light, and reduce the draw.

From what I have read, I seem to be within the guidelines laid out by Shorai... Only time will tell I guess...

FWIW

It's one of those marginal areas where the type of usage can make or break the deal.
It helps to know the numbers and understand what is actually happening. That was my problem as an early adopter of Lithium, blissful ignorance of the numbers.

Here is the RM23 data

Glen

This is off of https://granttiller.com/choosing-a-new-alternator

I dont know what the watt load was, so maybe Grant might know so you can do the maths from 5 amps?

Edit: fixed link address

I have a HO RM24, and had been using a Shorai for a number of years before earlier this year when just before a long trip my Pod crapped out, and I also replaced the battery with a lesser CCA AGM just in case., since I dont have a electric foot. Yet.

I also have a LED BSM in the headlight shell, but no volt meter on the bike.

At 12V Battery is still low and the LED maintains a constant red.
12.5 - 13.5V battery fully charged (engine not running) the LED will show orange.
Over 13.8V battery charging the LED shows green
Over 15.25V Overcharging. Fast red flash.

FWIW - Almost always at idle with the Shorai, normally the BSM would be green or sometimes orange.

The BSM is how I knew my Pod crapped out as it was showing orange/red when running. Seldom green.

The Shorai has held a full charge on the shelf since March.

Was this article about lithium batteries and Lucas components any use?

It's a good article but the info I'm searching for is alt voltage output vs rpm, no battery, standard 100 watt load.
Dave's site provided that for the RM23.
The high output version of the RM24 is obviously a lot stronger at low rpm, it would be nice to see it's output tested the same way.

worntorn said:

It's a good article but the info I'm searching for is alt voltage output vs rpm, no battery, standard 100 watt load.
Dave's site provided that for the RM23.
The high output version of the RM24 is obviously a lot stronger at low rpm, it would be nice to see it's output tested the same way.

Click to expand...

Maybe ask sales@elta.co.uk

Oh no, in that case I’ll have to take my Shorai‘s (using them on my Commando and 2 Triumphs since 2014) off cos they might go flat

Seriously though, I am using a 3 phase 14.5 amp, so looking at the chart, that clearly helps.

In fact, looking at the chart, and considering I have all LED bulbs and a Tri Spark (which has a low draw), and no indicators or electric clothing, etc, maybe I’d actually be better off with the 3 phase 10.5 amp to achieve a better load balance…?

I say fair play to Shoria, it shows good integrity as they didn’t just try and sell. They are being very conservative, empirical evidence from users shows clearly that they do work on Norton’s (and old Triumphs).

But, it’s true, I do not spend long periods at idle or sat in traffic (on any bike, bikes are for filtering)!

Been using a Shorai battery since '10 (the same one!) and although it is correct that, per Shorai, the battery is never at 100% charge, it hasn't mattered yet! For the first two years the charging system was the totally stock Lucas alternator/rectifier/zener. In late '12 I installed an Alton E-start so the Lucas alternator was removed at that time, replaced with the 150W Alton.

MexicoMike said:

Been using a Shorai battery since '10 (the same one!) and although it is correct that, per Shorai, the battery is never at 100% charge, it hasn't mattered yet! For the first two years the charging system was the totally stock Lucas alternator/rectifier/zener. In late '12 I installed an Alton E-start so the Lucas alternator was removed at that time, replaced with the 150W Alton.

Click to expand...

That is rather good to hear, I recently decided to try a Shorai on one of my bikes that has a 150w Alton alternator and was wonderin’…

Fast Eddie said:

Oh no, in that case I’ll have to take my Shorai‘s (using them on my Commando and 2 Triumphs since 2014) off cos they might go flat

Seriously though, I am using a 3 phase 14.5 amp, so looking at the chart, that clearly helps.

In fact, looking at the chart, and considering I have all LED bulbs and a Tri Spark (which has a low draw), and no indicators or electric clothing, etc, maybe I’d actually be better off with the 3 phase 10.5 amp to achieve a better load balance…?

I say fair play to Shoria, it shows good integrity as they didn’t just try and sell. They are being very conservative, empirical evidence from users shows clearly that they do work on Norton’s (and old Triumphs).

But, it’s true, I do not spend long periods at idle or sat in traffic (on any bike, bikes are for filtering)!

Click to expand...

Make sure you are using the MOSFET regulator, not a standard three phase Pod.

Well… on the Norton I’m using the Shindengen recommended by Grant. The main downside to these is they’re a bit on the big side.

On the others, they’re still on a mix of unkown cheap ones... Been looking at the Tri Sparks MOSFET offerings as possible replacements, which folk seem to rate.

Glen,
I have been using a Shorai battery with the Lucas 3-phase alternator and MOSFET regulator since installing the CNW electric start. I have LED head and tail lights.This setup has been on the bike for 3 years now with over 5,000 miles on it.The bike doesn’t idle very much as I am fortunate to live in a rural area.After every ride I always check the oil level and the battery voltage just to try to stay ahead of any problems. I would use this combination again as there have been no issues.
Just my 2 cents on this as you understand electrics way more than myself.
Mike

gortnipper said:

This is off of https://granttiller.com/choosing-a-new-alternator

I dont know what the watt load was, so maybe Grant might know so you can do the maths from 5 amps?

Edit: fixed link address

Click to expand...

Good chart - I know with my Alton Alternator, I am pushing the system voltage over 14 at about 2000 rpm, so it would seem it's performance is slightly better than the RM21 alternator. Alton states 90 watts at "cruising speed" (say 4000 rpm?), so if you consider a lead acid battery at 13.7 volts, that equates to 6.5 Amps. I would say I am now getting that after initially having a weak rotor supplied with the kit (replaced by Alton under warranty). With this kind of performance, I recommend at least installing an LED headlight with the Alton. A typical halogen bulb draws about 5 amps, gobbling up most of your alternator output.

I have been diligent about reducing my current draw as much as possible. I have all LED lighting, but I am running electronic instruments and my volt meter - but they are worth it in my opinion.

Fast Eddie said:

Oh no, in that case I’ll have to take my Shorai‘s (using them on my Commando and 2 Triumphs since 2014) off cos they might go flat

Seriously though, I am using a 3 phase 14.5 amp, so looking at the chart, that clearly helps.

In fact, looking at the chart, and considering I have all LED bulbs and a Tri Spark (which has a low draw), and no indicators or electric clothing, etc, maybe I’d actually be better off with the 3 phase 10.5 amp to achieve a better load balance…?

I say fair play to Shoria, it shows good integrity as they didn’t just try and sell. They are being very conservative, empirical evidence from users shows clearly that they do work on Norton’s (and old Triumphs).

But, it’s true, I do not spend long periods at idle or sat in traffic (on any bike, bikes are for filtering)!

Click to expand...

The trouble definitely comes when stuck in traffic with lights on, not when underway at decent speed. IIRC, Comnoz had a similar experience to mine when stuck in traffic at night, although I believe that just resulted in a dead battery and stalled engine, no melt down. It was Jim who explained about the internal low voltage cutout switch in Lithium batteries.
If you can always avoid that idling/very low rpm scenario then the bike will be charging for most of the ride, rather than discharging, so it's quite a different situation.
Shorai assumes that the user might get caught idling in traffic, hence the recommendation.
If one was to get caught in that mess, the 14.5 amp RM24 would be a big help.
Yes, bikes are for filtering. For some of us, they are also for long distance touring. When you do that, all sorts of unplanned scenarios pop up.
It's not logical, I should just ride one of the modern Triumph's instead, but my wife and I really enjoy touring on the old bikes.

Glen

Fast Eddie said:

Well… on the Norton I’m using the Shindengen recommended by Grant. The main downside to these is they’re a bit on the big side.

On the others, they’re still on a mix of unkown cheap ones... Been looking at the Tri Sparks MOSFET offerings as possible replacements, which folk seem to rate.

Click to expand...

What do you see at the battery with a DVM at idle with the Shindengen?

I've used the PODtronics reg/rect that includes the battery eliminator feature, and the Tri-Spark MOSFET reg/rec with a lithium battery. Both of them undercharge at idle if they idle long enough. (That is a contradiction to a statement I made a while ago. I thought the MOSFET was providing over 14V at idle, but I hadn't done the long idle test when I said that. Have done the long idle test since, and tears welled up in my eyes when I saw the results. ) Anyway voltage output ends up right around 12.9V with the LED lights on after 15 minutes idling with my single phase alternator. 13-13.1V with the lights off. I don't know if my alternator is a 10amp or 16amp. In my case 10 amp would be enough, but that is irrelevant. I did not run the test over 15 minutes to see if I'd lose enough voltage for the EI to quit. Edit: (Now that I think about it, I'm not sure that is possible unless I stall the motor at launch and the battery is dead.)

I'm tempted to try the Rick's Motorsports reg/rect, because it doesn't over charge with a 14.2V max output. The Tri-Spark MOSFET does overcharge according to the Shorai response and most of the lithium battery literature out there. Actually, I'm also tempted to try another reg/rect I found that has the same 14.2V max voltage output and costs a whopping $35US. That one might be a bike fire waiting to happen, but then again it might just be priced closer to actual cost.

Point is the MOSFET isn't really in spec. for lithium, so it won't buy you much other than I think it is a more robust part for a standard AGM, or lead acid battery.

Also starting to wonder if a PODtronics with the battery eliminator feature along with the lithium battery would be enough to sit at idle for long periods of time with the LED lights on and not have the EI die. I'd test that theory but the PODtronics lost an alternator leg after a short, and it's useless.

Still wondering why bother with all these worries whe n LeadAcid chemistry is what the original system was designed for?

In my case, it's not a Commando, and I don't have space or want to make space for a lead acid battery. I want a very small powerful enough battery for the EI and lights. Only other option is a magneto ignition and a battery eliminator reg/rect, but it's too late for retrofitting a magneto on my Norton. Too many modifications to get one back in there. Plus a magneto ignition would actually add more weight.

None of it is a worry for me. My Norton is just a toy to play with regardless of what it sounds like.

Tornado said:

Still wondering why bother with all these worries whe n LeadAcid chemistry is what the original system was designed for?

Click to expand...

Good question! I went with the Shorai initially because I was curious about them and needed a battery! Figured I'd try some modern technology! Later, when I installed the Alton E-start, I liked the small size of the batt which allows convenient placement of the Alton starter relay on the battery tray. Since the Shorai has worked fine for 11 years now - 3 times as long as any previous moto battery (!), it is my battery of choice for my Commando.

I'd put a Lithium batt in my old car but at 800 bucks, that's a bit more than I care to pay for a battery!