Shorai battery amp hour ratings

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After reading up what I can, it still seems that the Li is the best in terms of weight vs usable AH (FOR A TOTAL LOSS APPLICATION).

The benefit is smaller than the manufacturers would have us believe, as Glen has pointed out before, but Li does still win.
 
OK, I don't know anything about this subject so I have to ask, does a total loss/battery-only system really offer sufficient weight savings to actually make a difference for lap times on these bikes? If so, what are we talking about difference-wise in lap (or 1/4 mile -if that's the application) times?
 
MexicoMike said:
OK, I don't know anything about this subject so I have to ask, does a total loss/battery-only system really offer sufficient weight savings to actually make a difference for lap times on these bikes? If so, what are we talking about difference-wise in lap (or 1/4 mile -if that's the application) times?
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Charging system is extra weight, extra power loss and most importantly, an extra failure mode. Consider the engine will be running at, or close to, max rpm all of the time… but with very little draw on the alternator.

When you’ve spent untold thousands of £ and hundreds of hours building something as light and powerful as you can, the last thing on your list of preferred options is bolt on stuff which adds weight and saps power !

Is it possible to fit an alternator? Of course. But there’s just no reason or advantage to doing so when better alternatives exist.
 
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Yes, Lithium still wins the weight contest even when true AH is used.
It also wins for longevity. Solarpower users like Lithium batteries for their ability to withstand thousands of drawdown cycles vs hundreds with lead acid.

Glen
 
What are the dangers , if any, using a Shorai in our Nortons?
 
There's a small chance that something could go wrong with the battery and a fire would occur.
Also, Norton charging systems are not correct for a Lithium battery. Lithium requires a charging system that produces 13.1 volts at idle. Old Brit bikes discharge at idle, even with new components fitted. Lots of people ignore this and get away with it, but Shorai and other manufacturers do not recommend it.
If you are always attuned to the state of your battery and take steps to make sure the voltage doesn't get too low, then the Lithium should work fine.

Glen
 
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That being said, a Shorai 18AH has been in my Norton for over 10 years now with absolutely no drama at all and using the stock-type charging system. The first one lasted 9 years!
 
Fast Eddie said:
Would this charge a Li ?
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I think it would although it's a bit of an experiment. The charger puts out 17 volts which should be fine as long as it is regulated to stop charging the battery once battery voltage reaches 14 volts or so. The 10 watts is enough if the bike is running 25% of the time or less as ignition takes about 40 watts.
The ad doesn't detail this info so more investigation is needed.
I'm going to use one of these solar chargers for an electric start whole house genset. Usually these gensets are forgotten until needed, then the battery is dead.
Some youtubers have mounted one of these solar chargers on the genset enclosure and left it permanently trickle charging the battery. Apparently this works perfectly year in and year out, so I'm thinking the charger has a cut out or it would damage the battery.

I suspect that for racing the big extra lead acid battery and inverter for running your special charger would be a better solution. A 100 ah deep discharge battery would have enough power stored to see you through several race days.
Afterward you could just charge the deep discharge battery at home, or recharge it while driving your Van home, if setup that way.

Glen
 
MexicoMike said:
That being said, a Shorai 18AH has been in my Norton for over 10 years now with absolutely no drama at all and using the stock-type charging system. The first one lasted 9 years!
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Yes, that's why I added the bit about keeping the voltage up.
I ran into difficulties with night riding in the city. Everything shut down and we were stranded. Most riders don't ride old motorcycles at night in the city!

Glen
 
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I use a solar panel just a wee bit larger to keep the electric trolling motor batteries charged.
It keeps up ok and this trolling motor runs about 6-8 hours per day continuously. Draw is probably similar or slightly more than ignition.
How many hours of run time per day would the bike see?
The solar charger in the link has 10 watts of output. That is similar to many plug in trickle chargers.



Glen
 
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The big battery, inverter and charger is the way to go.
If the ignition averages 5 amp draw, then the 100ah battery should provide about 16 hours of run time thru an 80% efficient inverter.
There are modified sine wave inverters and pure sine wave inverters.
The pure sine wave inverters can also safely run your home electronics during a power outage ( or possibly your furnace, if needed)
 
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I track cars not bikes so probably shouldn't interject (but will anyway)

What about just having several batteries. Number would depend on size, discharge rate and length of event. Discharge is just the spark so how long will a battery last? I'd think you could get a couple sessions at least

And yeah, Li batteries aren't cheap but you wouldn't have to lug a bunch of gear to keep it charged. And what's the down time? Is it long enough to put a good charge on the battery

ok, i'll shut up now
 
TomU said:
I track cars not bikes so probably shouldn't interject (but will anyway)

What about just having several batteries. Number would depend on size, discharge rate and length of event. Discharge is just the spark so how long will a battery last? I'd think you could get a couple sessions at least

And yeah, Li batteries aren't cheap but you wouldn't have to lug a bunch of gear to keep it charged. And what's the down time? Is it long enough to put a good charge on the battery

ok, i'll shut up now
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Actually, I think you’re absolutely correct !
 
There are a number of ways to go about it.
The main advantage to a 100 ah battery and inverter is that it can also be used to run lots of things at home, if a power outage occurs. More and more people are using these setups for temporary power in built up areas. Often generators aren't permitted due to noise and exhaust fumes.
And it's really not much gear to drag along to a race either. A big inverter might weigh 7 or 8 pounds. The 100 ah lead acid battery will weigh a bit but they come with a strap and are quite manageable. Its the equivalent of about sixteen LFX 18 batteries so you won't run out of power.

It also gives you ac power for ac tool use at the racetrack or anywhere else you need it, camping etc.
I use our inverter quite a lot in remote areas.

Glen
 
Fast Eddie said:
Actually, I think you’re absolutely correct !
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Nooo! LiFePo4 batteries are expensive and they sit around doing nothing most of the time . Ok they might be able to take the the treatment better than other types of battery, but I lean the other way, sharing one battery between two bikes.
This is what I use for charging at the track (this one's 24V, but there is a 14V version): -
www.ebay.com

DC Power 12v 24v Step Up Regulator w/ Noise Filter SR-700-24 PST-SR700-24 NEW | eBay

DC Power 12v 24v Step Up Regulator with Noise Filter SR-700-24. Peak Output Power: 700 Watts. Output Current Limit. Short Circuit Protection. Continuous Output Power: 276 Watts. Box condition may vary & Serial # may be different than shown.
www.ebay.com
I don't know how I came across this, used to use it on my small lead acid batteries before going LiFePo, but it plugs into a 12V power supply (jumper cables + compressor thingy) and it boosts the output to 14V, no more, no less. Pretty useful for topping up a LiFePo between races. I have a charging port on the bike, so park the bike, plug it in for 15 minutes and its good to go again.
 
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