What kind of battery for adventuring, is Lithium up to the challenge?

Discussion in 'Parallel Universe' started by JoelWisman, Mar 6, 2012.

  1. ebrabaek

    ebrabaek Long timer

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    Ohhh dear..... I'm fraid I'l make you laugh...... I use a 22 year old Shack multimeter...before there were China.....from a WTO point..... But it is very accurate.....and I have not seen a need to replace it, until it dies..... I am on the springboard for this little piece though.......
    [​IMG]

    Perhaps foe the BD.......
    I'l measure up monday in the am....as I will be floating around tomorrow until late PM.......:thumb:thumb

    Erling
    #61
  2. JRWooden

    JRWooden Long timer

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    Thanks Joel!

    I've been out riding for the last few days on the coast ... no e-mail :D

    The 0.2 ohm series resistors would be an "easy" fix maybe ...
    I started thinking about wattage .... To produce 400W each stator leg needs to be putting out about ~9.5A

    9.5A^2 * 0.2 ohms = 18W or 54W total ...

    That's a high-side and simplistic estimate done by by a guy with very rusty EE skills.

    It got me thinking that the size of the heat sink on the stock R/R does not seem any too "generous" in size given that it needs to be able to disappate something like ~250W of surplus output from the stator when nothing was drawing power on the bike other than basic requirements & low beam headlight.

    I hope one of your R/R mfg. buddies comes up with something nice - thanks for asking them!

    As another data point, my F650GS which is now 3.5yrs old and has a new Deka battery installed reads as follows
    (using my venerable Fluke 77 meter):

    12.90 - resting overnight voltage
    13.91 - stable idle
    13.65 - 3K RPM

    THANKS!
    #62
  3. ebrabaek

    ebrabaek Long timer

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    Got home late last night..... and today is the day to show off my high tech meter......:D....

    Key off battery rest from overnight....
    [​IMG]

    Key on...engine off......
    [​IMG]

    Idle.....
    [​IMG]

    3000 rpm.....
    [​IMG]

    30 seconds after key off.....
    [​IMG]

    :thumb:thumb

    Erling
    #63
  4. TowPro

    TowPro Lets ride

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    very interesting video of Lithium batteries and the cold problem.

    http://ballisticparts.com/downloads/video/video2.php

    they show a HD that is in stone cold (upper 20'sF) with a lithium battery.

    what they are showing here is during the crank stage the battery will produce internal heat. They will do a short crank, let it sit for a couple seconds, do another short crank, let it set and each time you see how the battery works better as it heats up with internal heat. Long story short, after battery warms up from it's own internal heat, bike cranks fine.
    PS: Watch the volt meter when he hits the starter button. :eek1
    Remember as the voltage goes down, the required amperage goes up. I bet that voltage drop could weld the starter relay in the start position (Which does happen to older K100's with low batteries).
    #64
  5. JRWooden

    JRWooden Long timer

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    It appears you have a magic alternator or a miscalibrated VOM ....
    Could we trouble you to unscrew your R/R and post the markings on the back?

    Mine (lower voltage output) has the corporate logo for shindengen on the back, along with:
    SH541G-12 (Part number I think...)
    8.4022 (mfg lot/date code?)

    Schematic might be on this page: http://www.shindengen.co.jp/product_e/electro/catalog.html
    #65
  6. ebrabaek

    ebrabaek Long timer

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    Yessir.... I'l be right back.....:thumb:thumb

    Erling
    #66
  7. ebrabaek

    ebrabaek Long timer

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    Hereyago....2009...
    [​IMG]

    :thumb:thumb

    Erling
    #67
  8. NCD

    NCD Dirty Hairy

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    So, let's start looking on the back of RRs....I posted earlier that mine says SH541SC 0.0061 - and it has a small white paint dot inside the 'legs' of that molded-in capital A in the corner.

    Does SC stand for Super Concoction? Special Calibration? Silly Caucasian? Super Computer?

    Why does my bike charge different?

    (I just remembered that my GS911 reads voltage. Think that is worth looking at as a triple check?)
    #68
  9. JoelWisman

    JoelWisman Long timer

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    Thats all normal, it's just variance between meters. Notice resting voltage is 13.1. Lead acid does not rest that high once the surface charge is gone, it rests at 12.84 at the absolute most.

    All the meters on this thread are varying, mostly up which is the way they usually drift.

    All readings have shown the voltage higher at idle and lower at RPM except for NCD's which is the only one that is also a charging at a higher voltage that seems real.

    I'm completely satisfied. The F800 idles at around 14.1 volts and at rpm is around 13.85, from first year through the one I checked this afternoon which was another 2012, with at least one exception but i'm going to say that is super rare.


    ebrabaek, thanks, I did indeed laugh when I saw that meter, partially because I used to have one just like it, about 20 years ago :) The old Micronta meters were actually very good. I might still have mine but it exploded when I tried to measure voltage on a 2000 amp 480 buss with the leads in the wrong jacks.

    If you get it, the BK 5491B is an awesome meter! Takes forever to turn on, but so does my fancy fluke. Once it boots up, the 5491B is fast, accurate, and just laid out very user friendly. I don't own one, but used it at a friends lab.

    For the mere mortals on this thread..... HERE is a 1 hour review of 5 cheap multimeters.

    THIS is the cheapest meter I own and would feel fine about taking with me on a cross continent ride.

    Money no object? THIS is the multimeter I wish I owned for everyday shop work and rides to the four corners. Will double as offensive weapon.


    Towpro, You hit the nail on the head. LiFePo4 needs to internally heat to provide full cranking amps, and not just when cold. Even warm LiFePo4, batteries that will start your bike fine have a large voltage drop for the first few seconds. Enough so, that even on a warm day, the the battery recommended for some bikes by some manufactures will be damaging bikes starting systems over time IMO.

    The K100 isn't the only bike who's starter relay can weld together or just burn up, I have seen this happen on two F8's as well, though both with crappy oe batteries.

    Further, though its not an issue with the F8 since its starter uses a sprag clutch to transmit starter power to the crank, some bikes including the BMW boxer bikes use a bendix or solenoid to force the starter pinion onto the flywheel ring gear.

    On these bikes, under voltage during cranking will over time destroy both the starter and ring gear, necessitating removal of the transmission to repair on the BMW boxers.

    I'm going to get into cold weather tests and all of the above, but first I have to find a LifePo4 battery that passes my tests when warm, which the LFX18 from Shorai does not.

    Stay tuned :)
    #69
  10. JoelWisman

    JoelWisman Long timer

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    I'm satisfied that your bike IS charging different as the readings are consistent and the drop in voltage at RPM that even the worst multimeter would pick up isn't there.

    As to why? Your regulator is either defective in a pleasing way, or BMW is fielding some test units.

    All manufactures secretly do this and none will ever admit it or do anything about it when caught.

    Either way, I wouldn't worry about it, because what your regulator is doing is what others should be wishing theirs did :)
    #70
  11. ebrabaek

    ebrabaek Long timer

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    I had a feeling you would at the very least giggle Joel....:D:lol3:rofl

    :thumb:thumb

    Erling
    #71
  12. JoelWisman

    JoelWisman Long timer

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    Highly delayed, but ground work for posting video and text results for fixed, variable, and in motorcycle current delivery tests of batteries.


    Current delivery ratings are ways to quantify how much juice a battery can deliver in a short period of time.

    Amp hour ratings of batteries can be compared to fuel tank size. A larger gas tank will allow you to ride further, but it has little affect on how fast your bike will go.

    CCA and other current delivery ratings of your battery are analogous to how many horse power your engine puts out at full throttle.

    All batteries have internal resistance as well as other variables that affect high rate current delivery. As current demanded from a battery gets high, the battery voltage lowers temporarily due to the above.

    How much the voltage lowers depends on how much current is demanded and the batteries ability to deliver which is quantified by battery current delivery ratings.


    Lets say battery (A) has an honest 200 CCA rating. Battery (B) has an honest 300 CCA rating.

    Now lets say the bike we are starting is a Moto Guzzi Stelvio 1200 NXT and it’s 70F out. Under these conditions the Stelvio will draw around 180 amps while the motor is being cranked over.

    With battery (A) installed in the Stelvio, the battery terminal voltage will drop to perhaps 10.8 volts in the 5 seconds the engine had to crank before starting.

    Since battery (A) has a 200 CCA rating that the Stelvio starter did not exceed, is there any difference when using a higher CCA battery?

    You bet! With battery (B) installed, the terminal voltage would only fall to, say, 11.3 volts.


    So why all the fuss about voltage? Voltage multiplied by current equals POWER, and power is good :)

    First is the effect on the starter. We have probably all experienced a bike cranking slowly or maybe not at all due to a low or worn out battery. This happens because such batteries can’t keep the voltage up. Likewise, battery (B) keeps the voltage higher then battery (A) and will crank the engine over that much faster.

    Faster is better because it is more likely to start your bike. Either of these batteries will start a well maintained Stelvio on a warm day, but what if the Stelvio is not happy? Lets say the fuel injectors are a little plugged, spark plugs are a little wet or fouled, you filled up with old or shitty gas..... I could go on and on, but suffice it to say, for whatever reason the bike is harder to start then usual. In this case a higher CCA battery will turn the engine over faster which lowers compression loss, reduces the time fuel has to condense when cold, and turbulates and mixes the charge in the combustion chamber more. The above will make the engine more likely to start.

    Cranking terminal voltage also has an effect on other things. Fuel injectors can stick from time to time due to internal corrosion or fuel varnish that acts like glue. Fuel injectors are opened by an electric solenoid. A fuel injector that sticks closed with the stock battery will often open and work free if higher cranking voltage is maintained because the voltage the fuel injector solenoid sees is directly proportional to how hard the solenoid pulls. More power is better!

    The same is true of the ignition system. When the cranking voltage is higher, the coil(s) produce a stronger spark that is more likely to ignite sub optimal fuel mixtures.

    The list goes on, but take it from me, CCA matters and MORE power is BETTER.

    During my 20+ years in the service industry, I could not even begin to count the number of vehicles towed in that I started simply by attaching a boost charger or large jump battery. In most of these vehicles something was wrong that had nothing to do with the battery, but more power allowed me to start these vehicles and drive them into my stall, and nowhere was this truer then my time in a BMW motorcycle service department but i’m sure this holds true for other brands as well.

    Further, more battery power is better for the bike starting system in several ways. Bikes using a sprag clutch to transmit power from the starter are not damaged by low voltage (though under low voltage they certainly won’t start the bike) but some bikes use starters that must shove a pinion into the flywheel to transmit starter power to the engine. Whether done by bendix or electromagnet, these starting systems can destroy themselves and the flywheel ring gear when repeatedly operated with low voltage because the power applied to the starter can be to low to fully engage the pinion.

    Next up, the starter relay contacts are themselves propelled together by an electro magnet. Too low of voltage and these contacts will chatter, arc, weld together or melt down.

    Enough power is ok. Too little power is bad. MORE power is better :)

    On an adventure bike that just might be 500 miles from a dealership when something goes wrong, more battery power can make the difference between joy and misery.


    The terminology.....

    CCA (Cold cranking amperes) was coined and defined by the Battery Council International and is defined as follows:
    “The number of amps a battery can deliver for 30 seconds, without falling below a terminal voltage of 7.2 volts (12 volt battery) when the battery is 0 degrees fahrenheit (-17.7C)”.

    Later this definition was standardized and adopted by S.A.E. and precise test methods are contained in SAE J537


    CA also called MARINE CRANKING AMPS is the same as above but at a temperature of 32 degrees fahrenheit (0C).


    HCA is “hot cranking amps” and is the same values as above but at 80 degrees fahrenheit (26.7C)


    PHCA was coined by Odyssey. It seems to be the number of amps that can be supported for 5 seconds which is reasonable as one rarely holds down the start button for 30 consecutive seconds and still has a starter motor that is not on fire, but since Odyssey did not go on to define “down to what voltage” the term is not yet useful.


    CCA PBEQ (PB= lead, EQ= equivalent) This term as used by Shorai is meaningless. The reason I call this term meaningless is that it implies that one can use this number and get comparable performance from a Shorai battery to a lead/acid battery with the same CCA rating when You can not.

    LiFePo4 power sports battery manufactures certainly can’t use SAE J537 to rate the CCA of their batteries because the test methods do not account for LeFePo4 batteries needing a period of current flow and then rest before full CCA can be realized.

    They could however write CCA*1

    “*1 CCA achieved after cranking for 5 seconds then resting for 1 minute to internally self heat lithium cells”

    unfortunately since battery sales have always been driven by ratings, once Shorai (I believe they were the first) made up this BS term, other manufactures had to follow suit or die.


    How to test the for the actual CCA of a battery:

    Simple. Take a battery that has been cold soaked at 0F, apply X number of amps continuously for 30 seconds. Record the minimum terminal voltage throughout this test. If the reading remains above 7.2 volts, recharge the battery and apply higher amps until you find that magical number or at least the number you wish to advertise on the battery.


    Some time ago, manufactures of cheap batteries successfully petitioned BCI to come up with a gentler field test for battery CCA. I don’t remember all of the posited reasons, but the real reason IMO is that especially as it ages, a cheap battery will have too thin of a buss to sustain a full rated CCA load without the buss burning through or cracking.

    There are other reasons, technicians didn’t like wheeling around a carbon load tester and preferred a cute low power hand held, and also if the buss does burn in half during the full scale test, the battery occasionally explodes.


    I am a stickler for tradition when tradition works :)

    On quality batteries, CCA means this battery really WILL put out this much current when fully charged

    Up next, actual CCA tests :D
    #72
  13. REVjimenez

    REVjimenez ESSCAPEr

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    Off topic but EWWWWWWWWWWWW, you gots that famed Rally Moto steering damper I have on my 1200 GSadv...loverly bit of kit...
    #73
  14. REVjimenez

    REVjimenez ESSCAPEr

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    First a thanks to all who contributed on this thread...fantastic bit of engineering information provided, and sure makes the decision tree a might bit easier for now...

    In kind, about four weeks ago when I had interest in buying a couple of Shorai batteries for my KTM 690R and the BMW 1200GSadv, I went down to my local Savannah Batteries Plus franchise and inquired within...what I got both from a sales person and the manager was the following reasons why they do not and will not stock the Shorai or other Lithium Ion batteries:

    1.) To start with, Federal laws (and some state laws) require large scale resellers of the the Lithium based batteries to set up a special process for
    (a) storing old batteries
    (b) transporting old batteries
    NOTE: neither could tell me what defines a large scale reseller nor the exact statute of law governing disposing of used batteries.

    2.) Because of the heat involved on differing Lithium Ion batteries in differing bikes, they won't take the liability of the battery bursting into flames...I was initially confused by this, but the manager knew about the Tesla Coupe and the fire damage as well as the overheating problem (the Coupe is now water cooled batteries I believe)...

    3.) Most OEM car or motorcycle battery holders are too big for the Lithium Ion battery holders.

    4.) And, lithium Ion batteries are typically a factor of 1.5x or greater in price compared to the standard battery as of right now...though business has been a bit off over the last 3 years, they have sold more of an inexpensive line of batteries and thus for the foreseeable future, they don't see how they would be able to sell higher quantities of a more expensive battery...
    #74
  15. GoneAgain

    GoneAgain Huh?

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    great thread Joel...love your work :clap

    anyway... i figured i'd have a bit of a poke around with a multimeter and see what i had....

    you ready :evil ?

    ok... i rode 400km so the bike was hot... ambient temp 28.5 according to BMW...

    i got home, stopped bike went and got my meter (cheaper 'dick smith electronics' (think radio shack i suppose) that ive had for a few year...measures just about everything.. started the bike and stuck it in the accessory port next to the ignition...

    idle (approx 1100-1200rpm) : 14.27v
    started to rev up to 3k rpm, fan kicked in, so with fan running at 3000 rpm : 14.12v
    dropped back to idle with fan still running : 13.5v

    let her idle for a min or so and fan shut off...reved back to 3000rpm without fan : 14.31v

    dropped here back to idle and something weird happened... all i could get was 9.8v (reving or idle... :deal )

    switched here of, waited a minute, started... still could only get 9.8v :eek1

    left her 5 mins, started, no fan connected meter and immediate reading was 13.8v, but this kept climbing over about 15 seconds of just iddling to 14.25v
    reved to 3k, still no fan, 14.25v :clap

    so i figured i should go direct to the battery:evil

    went and fueled up so my fuel light wasnt on..

    ripped the panel off, cleared away the dead bugs and fired her up again

    28.0 degrees,

    meter started at 13.1, but climbed constantly over about 20 seconds and stabilised at 14.31v
    reved up to 3000 rpm : 14.33v
    drop back to idle 14.33v (no change:deal )

    then just to prove the meter would display a different number
    heated grips on : 14.26v
    plus high beam 13.24v
    plus fan kicked in 12.64v
    high beam and heated grips off, fan still on : 13.55v
    fan cut out : 14.33v :clap

    so......

    there you go..
    she's a 2012 (about 4 months old..

    i haven't gone looking for purple dots yet :D

    cheers!.

    .
    #75
  16. JRWooden

    JRWooden Long timer

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    If you have a chance to look for those dots :wink: & get the part number off the back of the R/R please post?
    Thanks!

    It is curious that a few bikes seem to be charging "correctly" at 14.x volts while the majority charge at a "less than ideal" voltage............... :cry
    #76
  17. JoelWisman

    JoelWisman Long timer

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    I'm telling you, BMW is running a test and substituting some regulators, at least that is what I suspect.

    When I was with Volvo, we would go so far as to grind off part numbers on conspicuous parts we were substituting and stencil the normal part number back on, or pick a new part number out of thin air.

    A part number I picked once was 8273558. The first 4 were my birthday and last 3 were same as original part # :)

    It happens, manufactures and occasionally distributors do this. You don't need a special part number or colored dot unless you are going to call for the part back and want to make sure the dealer sends you the actually part and not just an equivalent part.

    You usually don't need the part back, you just track what happens through the VIN warranty file.

    In BMWs case, they will be looking to see if the alternate R/R fails, if the battery seems to fail sooner or later, if the ZFE or DME wig out from electrical noise, if the regulator gets so hot it makes grill marks on the riders leg, and for any other occurrence no matter how far fetched that seems to go with the part substitution.

    You have to understand. Engineers with both the parts vendor and vehicle manufacture vet parts with huge mathematical equations and super computer simulations. Then hacks like me build test beds and throw whatever we can think of at the parts. Next it goes onto the internal fleet of test bikes and if you don't like them, it goes onto the corporate vehicles of ranking staff, without their knowledge. The last is the true beta test. Neither BMW or Volvo beta test on customers though it may seem like it.

    All of this takes a year or two, which is why vehicle manufactures constantly get accused of taking forever to address known issues that you bet we don't acknowledge to customers as that only pisses them off worse.

    Next up, the new part secretly goes onto a small number of vehicles picked at random. Dealers are not informed, often distributors like BMW Motorrad NA are not informed, the customer is absolutely NEVER informed.

    Once on a customer bike the real test starts because no matter how long you simulate, stress test, and run the part on the internal fleet, customers will do things that never ever would have occurred to corporate.

    If the need is urgent, say brake lines are cracking or such, engineers take their best guess, over-ingeneer and release the new part immediately. That is how you end up with recalls on your recalls :)

    Either wary, manufactures are not transparent because they need a blind tests to truly vet new parts AND because to be honest, there is a bit of a herd mentality with customers. I am NOT putting anyone down! If I still owned an F8 I would be part of the herd and depending on which way I was wired, either disappointed I had the old regulator or stressed that I had a new un-vetted regulator.


    Speaking of un-vetted...... I have modified two F800GS charging systems by inserting resistance between the stator and R/R. I ended up going with 0.09 ohms and saw peak charging power go down to 379 watts, idle charging power was not measurably affected. Stator temperature is the same at idle but down 9C at 4,000 RPM which is better then expected.

    One rider is local and the other hales from AZ. Both riders are sworn to silence to maintain warranty i.e. this test is blind to even BMW lol.

    Assuming these bikes don't explode in the next 2 months, or have the stators fail, i'll post how I made the changes and others can jump in on the experiment if they decide to.

    All for now, back to testing batteries, wish me luck as the last battery I tested just released a cloud of hydrogen in my living room :)
    #77
  18. JoelWisman

    JoelWisman Long timer

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    CFR49 governs transportation and disposal of lithium batteries and a few states have additional laws on the books having to do with recycling. Federally, if you are accepting or transporting more then 210lbs of lithium batteries a month for disposal, you need a special permit.

    It is illegal for consumers to throw away lead/acid batteries in all 50 of the United States, which of course does not mean you can't, it simply means you will be breaking a law that has no enforcement mechanism I am aware of. It is actually legal to throw away lithium batteries in many locals.

    Personally I am a fan of recycling. For lithium battery recycling, including the LiFePo4 batteries I am testing that got in bikes, Call2Recycle accepts them free from consumers. They have a zillion drop off locations including 9 within a 5 mile radius of Savanna GA.


    The fire in the Tesla was actually caused by a wiring fault that was on a circuit powered by a small lead/acid battery, read this LINK The coolant fires, especially in GM products is owing to the use of flammable coolant on huge traction batteries. None of the lithium starter batteries for motorcycles or cars have any coolant of any kind, so I wouldn't be concerned about that aspect.

    The fires from smallish batteries like laptop batteries that have made all the news are in packs using Lithium manganese or lithium cobalt chemistry. The brand name SLI batteries I am testing (AntiGravity, Ballistic, Shorai) all use Lithium ferrous phosphate chemistry which is a hell of a lot safer. To date, I have not heard of any LiFePo4 batteries causing fires on motorcycles, just releasing a cloud of mainly steam and getting hot enough to melt some plastic.

    Lead/Acid batteries can fail this way too, and as it happens, a YTX12 lead/acid battery that is in my test group released a cloud of hydrogen while I was testing it about 12 hours ago.

    I am not schilling for the lithium SLI battery manufactures and so far have been anything but impressed with Shorai's product, but..... Having watched video of LiFePo4 batteries deliberately melted down by hard shorting the battery terminals, it is less exciting then what lead /acid batteries do when you short them the same way.



    This is a plus in my book. At the least, Shorai and Ballistic ship with foam to use as a spacer so their battery can be shimmed to fit the same compartment and use the oe hold down, but I like free space to store tools or whatever. These batteries are so light you could safely hold them in place with velcro or zip ties!



    They are expensive and longevity claims to off set this are not yet proven by time. You loose some weight and gain space, but if these batteries are worth the price is going to vary depending on your priorities, desires, and how these batteries actually end up performing.


    Concerns about emerging technology are fair, but I think your Batteries Plus is being a bit unfair and alarmist.
    #78
  19. JRWooden

    JRWooden Long timer

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    Thanks Joel...

    1) The part of this I was not focusing on was that the "new" R/R might be camouflaged ...
    I had "assumed" we'd be able to tell them apart... sigh.........

    2) Where can I get a job as a "hack" :lol3

    3) If wire insulation follows the "norm" (10C change in temp. doubles/halfs the rate of reaction)
    9C would almost double the life of our stator ... sign me up to loose 20W of output!
    What wattage rating resistors did you use? I would think 10W would be more than adequate?

    In other news, I have a conversation going with one of the guys from ElectroSport, I'll post it here once I confirm he does not mind that I do so - one of his ideas was to use a better grade of wire so that resistance would be less and thus I^2*R heating would be less as well ...
    #79
  20. JoelWisman

    JoelWisman Long timer

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    I didn't bother trying to find a zillion watt resistor, just used nicrome wire cut to length for resistance and sleeved it in fiberglass braid.
    #80