Motorcycle Batteries .. AGM, GEL, Wet, Lithium Iron Phosphate (LiFePO4)

Discussion in 'The Garage' started by _cy_, Jan 20, 2012.

  1. _cy_

    _cy_ Long timer

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    RC folks were the first to harvest A123 cells from lithium tool battery packs. note A123 (26650) style batteries is also included in this category. chinese have been making A123 clones for sometime.

    http://www.rcgroups.com/forums/showthread.php?t=1415041

    Real A123 CARDBOARD SLEEVED harvested from DEwalt power pack

    ALL SOLD, THX RCG

    2cell pack SOLD pending funds
    $35 TAKES remaining 5 CELLS SHIPPED

    Or $6.50 per cell if buyer pays shipping----Paypal OK

    Like new, Only 10 to 15 cycles on them

    Shown here in a one, two, & four pack configuration with 4mm bullet connectors

    I did them this way so I could easily try different combinations for power
    IE: 1, 2, 3, 4, 5, 6, or 7 S
    The resting voltage for 7 cells is 25 volts for an average of 3.57 v per cell

    Thanks for looking,

    Roger aka GIFLYRC
    <fieldset class="fieldset"> <legend>Attached Thumbnails</legend>
    • [​IMG] individual packs shown shrink wrapped one cell, 2 cells, & 4 cells 64.7 KB · Views: 36
    • [​IMG] Shown connected in series as a 7s1p reading 25 volts for the pack, other combinations possible 1s thru 6s 53.2 KB · Views: 76
    </fieldset>
  2. Anorak

    Anorak Woolf Barnato

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    I remember when DeWalt and their other brands used them. Note the past tense. A more simple answer is none, currently. So far as clones, those aren't A123, are they? A123 "style" batteries shouldn't be included because they aren't A123. In the right situation, that would get you a cease and desist from A123's legal department.

    You've spent a lot of time in the very detailed minutiae of your tests with plenty of obscure terminology which I would hazard is not understood by a majority of the people interested in the batteries. And then, as I pointed out several times in this thread, I as a layperson somewhat familiar with the technology found many mistakes in your descriptions of the various chemistries. In my opinion this subtracts from your credibility

    Mr. Wiseman seems to be taking a much more practical approach to the subject. Run the crap out of the battery and see what it takes to kill it. The eight A123 26650 cells, two sets of four in series paralleled potted in silicone with a bms, I've been using in my car for the past couple months have been flawless. The starter draws 320 amps.
  3. _cy_

    _cy_ Long timer

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    one of the advantages of 26650 A123 style cylindrical cells is hugely increase structural rigidity. with large surface area to spot weld metal bands in series. prismatic pouch cells have limited support for terminals. this arrangement allows a variety of shape and sizes. allowing large AH and small AH cells to be made.

    4 cells are less likely to go out of balance vs 16 or 20 cells. especially as cells age.

    yes I like Shorai batteries purely because that have never given me reason not to. for instance... since I've never needed to crank a battery in real life for 14 continuous seconds. why would I subject Shorai to that test?

    what I have done is crank LFX 21 repeatedly for 5-6 seconds with a 200 amp load ... until I got bored doing it. that is NOT a gentle test ... repeatedly subjecting a battery to 200 amp loads on end for 5-6 second cranks.


    not done yet, but after charging and discharging Shorai batteries many cycles. with intelligent and dumb chargers both.... starting to come to conclusion Shorai batteries are internally balanced.

    I'm not going to tear open good functional Shorai batteries. but you've got three dead batteries that could be opened up.

    don't consider doing tests that mirror what a motorcycle rider gentle. what I would call that is real world testing. IMHO testing to destruction with tests that would never happen even in extreme situations serves zero value.

    again .. would agree that Shorai over rates their batteries. my choice would be the FLX 36 for adventuring, just to gain extra margin.

    if you mean a 14 second 200 amp load on LFX 21 ... I'd consider that destructive simply because almost no one would be doing that in real life.

    appears a major part of problems is how Shorai rates their batteries. perhaps these tests should have been done on a LFX 36

    didn't realize Shorai were not waterproof... thanks for pointing that out... a few dabs of silicon should fix that issue.

    yes I do like Shorai for the simple reason they have never given any reason not to. I've flogged them repeatedly at 200 amp loads but only for 5-6 seconds per cycle.

    Let's be real... if a motorcycle doesn't start after 5-6 seconds of solid cranking. something is wrong and needs to be addressed. before you go melting your starter.

    and no I would not be recommending a smaller Shorai or a smaller Ballistic, smaller Anti Gravity or any other smaller LiFePO4 battery for Adventuring.

    what I initially started to use for R80G/S and still may ... is a 20 amp hour (actual) LiFePO4 battery with balance/over charge circuits.
  4. JoelWisman

    JoelWisman Long timer

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    Okay, your reasoning is starting to make more sense to me _cy_, but let me point out where mine differs.

    Your test and experience bed seems to be a carbed BMW R80GS with almost zero electronics.

    Firstly, a compliment is owed. Keeping an R80GS running well without needing monthly visits to a dealership requires talent. Unless I read you wrong, you do all of your own work, so through training or significant experience, you must be a good mechanic in your own right.

    On a side note, what are you using for points? If you converted to breaker less, well thats what I would do, but for those whiting to stay stock, the oe points are now made in mexico and don't hold up, have you found any that do and know where I can source them?


    Okay, back to my experience. The adventure bikes my battery thread is for are all fuel injected and most quite complex. If they don't start after two seconds of good cranking, something is wrong.

    Things go wrong ALL THE TIME on these modern marvels. To sort it, you usually need to either start it, or crank and crank while looking for what is missing.

    Fuel pressure is easy, a gauge is ideal, but lacking that, get used to how the fuel delivery hose feels under system pressure (usually 42 PSI), crank for a few seconds and feel to see if it seems right.

    Good, move on. Not good, crank for a LOT longer. The problem could be....
    1: No duty cycle signal to fuel pump controller. (a meter should read something and usually bounce all over)

    2: Broken ground or positive out from controller. (pull it out and test)

    3: The wrong duty cycle from controller. (hope you have a scope in the bush with you, if not, crank and take a long reading with meter set to min/max/average)

    4: No B+ to controller. (test. There are no fuses in a modern BMW but rather a basic controller which is a set of solid state switches controlling many things with some logic and current sensing. Sometimes they bug out so crank for a while and it may go into limp home mode or reload firmware from NV ram)

    5: No B- to controller. (Test, this is a simple connection to ground)

    6: Bad check valve causing it to take 15+seconds to build fuel pressure and displace gas vapors that result. (check valve is in the pump and not removable so all you can do is crank a long time to build pressure and replace the pump when you reach civilization)

    7: Stuck open regulator which causes it to take forever to build fuel pressure and require the pump to have higher voltage before it will again proper air/fuel ratio (this one really takes a long continues session of cranking and is not that uncommon. The regulator is in the tank just above the pump in non return systems. You could pull the pump and apply power to check it, but you need to be pumping something for it to tell. Water will damage the pump so gasoline is probably the only fluid on hand that will work. The pump has brushes that arc and rely on the air fuel mixture in the tank being too rich to support combustion, but once you have the pump half out, all bets are off.

    The bitch is the regulator usually sticks in the wide open position well away from where it needs to be for high fuel delivery rates for cold starting during under voltage from cranking, BUT, if you crank and crank, the DME will slowly lengthen fuel injection pulses to try and see if richening will start the bike, which it will, but not before 15 to 30 seconds of continues cranking. short pulses of the starter will do nothing as the fuel trim will reset to zero each time you release the starter button.)

    8: Bad ground to DME. (There are actually 4 grounds that need to be present to the DME on a modern BMW, test all 4 but realize, they may be opening under load so test for voltage while cranking.)

    9: Bad hot to DME. (This is controlled by the basic module, crank and crank while testing. the basic module may need to reset or there could be a CANbus communication issue or the wire could be open, or it could be shorted and the basic module has opened the circuit but will retry every 5 seconds or so, so crank and crank while pulling on various parts of the harness. Or remove the harness and untape it. good luck with that, takes about 4 hours in a shop if your experienced.)

    10: Open safety circuit, such as side stand, clutch switch, kill switch, tilt switch, (test, test and test. if it ohms out ok, try while cranking, sometimes it opens under load or is shorted to something else that goes live while cranking)

    11: Scrambled DME firmware in HS static ram, (hold that start button, it will begin reloading from NV ram if you crank for long enough for it to realize the static ram is corrupted. You can also remove the battery leads, short them, and wait about a day for the capacitor that keeps the static memory fresh to drain through the high omit connection through leads and ram load, hope you have warm sleeping gear)

    12: Stuck fuel pump. (beat on it while cranking and the higher the battery voltage is the better. If this doesn't work, pop the controller off and go direct from the battery, jog it in both directions but realize that if it is super stuck and you aren't using a fused jumper, the wires will burn in half inside the fuel tank)

    13: Bad fuel pump controller. (go direct from battery and disconnect each time you stop the engine. you really want to use a fuse, 10 amp should do. note on the K7X and K16 platforms the pressure will be way to high BUT the computer will compensate if you crank for a really long time and get it started)

    14: Open fuel pump winding. (you are screwed, hike or hit your spot)

    15: Fuel pump brush stuck or on dead winding or grunge on commutator, bang on fuel pump flange as you crank, often takes a long cranking and beating session to free this, the same with a stuck pump, but beating without potential at brushes does nothing so crank and crank. (crank and crank and crank while you beat it)

    16: Bad fuel pressure sensor. (If it is truly bad, this will be masked and the pump will operate at a fixed duty cycle, but the fuel mix will be way off, crank and crank while the DME mods fuel mixture hunting for that magic ratio. remember, short pulses of cranking do no good cause the fuel trim resets to zero each time you release the start button. if it is just sort of bad, the bike will never start, so pull the connector and crank and crank until the DME finally decides the FP sensor is broken or disconnected and then crank some more as it sets a fixed duty cycle on the pump and hunts for that magic air/fuel ratio)

    If fuel pressure was ok, then it is likely one of 72 wires to the DME are open, shorted, or high resistance, or it could be a problem with the intake air temperature sensor, engine temperature sensor, oxygen sensor or its heater circuit, throttle position sensor, crank position sensor, cam position sensor, plugged, shorted, stuck, or open fuel injectors, or perhaps its not in the fuel management system at all, could be the ignition system which has a whole lot of wires and sensors itself. could also be a CANbus communication issue.

    These are the common problems I have run across in my professional career but there are obscure possibilities as well.

    It's rather daunting even to professionals like myself, especially when trying to figure out problems by email, forum post, cell phone or text message so don't feel bad if you simply decide to scrub your dream trip and fly home :(

    OR, you can select a battery that will hold up to prolonged continuous cranking and many issues will sort themselves or at least be masked out and limp home modes activated.

    For what it is worth, most often beating on the pump and injectors while cranking for an extended period will get you back up and running, as long as your battery is up to the task. And on a positive note, stuck fuel pumps and injectors are far less likely if you choose a battery that keeps the cranking voltage high as this same voltage increases the force with which the fuel pump applies torque to the rotor and solenoids alloy force to injector pentle.


    _cy_ does my different take on the need for a battery that can do prolonged cranking start to make sense when talking of modern fuel injected adventure bikes?
  5. _cy_

    _cy_ Long timer

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    joel... good grief that's a LOT of cranking! No wonder you are so keyed in on long crank cycles. this puts a completely different light on things. getting a load of bad fuel in an R800GS, then having to crank the devil out of it to back going again is very much real world.

    so for a modern bike cranking times a battery needs to sustain would be 15 seconds. but load requirements would go down slightly. typically amp loads will lessen into long crank cycles. assuming current draw would be about 150 amps. this means LFX 36 is the only Shorai that would likely meet adventuring requirements for modern BMW bikes.

    yup you read correctly no visits to the BMW dealerships for me and I'd like to keep it that way too.
    that's why electronic ignition is getting yanked soon. would have done it already except for difficulty in locating a bean can with points. which only was used in 79-80 airheads. finally lucked out and found one on fleabay for $35 + $9 shipping.

    your above list is exactly why I'm not running electronics. will be a long ways from any support. so anything remotely has a chance of breaking will be taken care of before leaving RTW. much cheaper to ship transmission off to a specialist for total rebuild with a new clutch vs dealing with it on the road.

    here I just did a no no ... freshening up the old points with emery cloth until I can find new ones. sure hope I can find some nice German Bosch points.

    [​IMG]
  6. _cy_

    _cy_ Long timer

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    yup that's why I've used the terminology "A123 style 26650 batteries" for the exact reason you pointed out. A123 was the first ... many followed with clones, some claim better, some say not as good, etc. etc.

    keeping track of which lithium power tool uses what brand battery is pretty low my list. what's more useful is knowing A123 style batteries enjoy the latest improvements. simply because economic incentive to improve performance is the highest with 26650 cells.
  7. Antigravity

    Antigravity Been here awhile

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    Cy I don't think you get it, when you post something that is not accurate many people read it and may take it as fact. So I have to make sure if someone like you who is supposedly "unbiased" is posting facts, and not posting things that I have to defend because they are inaccurate or misleading. This effect a smaller company like Antigravity who at this time can't compete with full page ads of Shorai who you seem to cater too. Earlier I presented proof that the A123 based batteries in Cylindric format ARE in fact more compact than the Prismatic form (in motorcycle use) while offering much more Power and similar amp hours, yet you are willing to claim your statements are "right on the money". You are not close to on the money. You original post was to give info on the batteries in the application of adventure motorcycles, and you made a claim that the cylindric format uses more space giving the impression it was larger... I just wanted to correct the implied statement.

    .
    Sorry this doesn't fly, you are supposed to be an "unbiased tester" not "fair". There is nothing unfair about doing hard testing.... The readers probably want to know what can handle the most abuse. It is a sign of QUALITY.... Why do you think Ford or Chevy has commercials showing their vehicles towing massive payloads beyond their capacity... why do you think Castrol Oil tried to blow up motor using its oil on those commercial..... it because they want to show their product went BEYOND normal use and handled it. That is why those independant labs beat the hell out of products and test them beyond their capability.

    You are correct 90% of the people won't use a product in a torture test... but don't you want to know which one lasts the torture test if you researching for the best product? I feel your copping out...you claim you wanted to test for which battery could handle world travel...yet you are only testing voltage and amp hours.... not really much if you claiming to be "testing" a battery to see if it handles world travel. Isn't waterproof important in testing? Adventure guys see lots of water.

    Cy you were implying it and you are actually talking out of context to what your thread is about... You are trying to prove a "disadvantage" of the Cylindric A123 to the Prismatic Cell in space/size (your Shorai bias?)... BUT in fact there is not one in the application of Motorcycle Batteries, the opposite is true in fact. We are talking bike batteries and their viability in Adventure Bikes,correct? So in fact your statement appears to specifically point out a supposed "disadvantage" in size/space savings that does not really exist in this application. This is the reason I had to start posting in the thread. I felt it was misleading and seemingly biased. You have promoted one product here with favorable reviews without having the other products to test in a similar arena, but then you start making statements of "disadvantages" in the other product which you HAVE NOT tested. Does not seem unbiased.


    The actual reason is because the cell is a proven durable performer and world class companies know it works... so yes the technology goes there first and foremost to create and even better version... and that is great for the consumer and A123 has the new 2.5 Ah 26650 out now....

    Another highly noticable oversight on your part is you seem to be lumping in the A123 26650 Cell with the other knock-off 26650 Lifepo4 Cells....but you FAIL to mention that those other companies making the the 26650 Lifepo4 Cylindric Cell cannot even produce the performance and durability of the A123 26650 Cell which is capable a pulse discharge of 120 Amps per cell and has a 70amp constant current ability while the other knock-off 26650 can do only 40 amp discharges... when you are talking battery cells and knock-offs of the A123 cell It is actually like comparing a Harbor Frieght tool to a Snap-On. The Cells are that different in quality and perfomance... being the same size has NOTHING to do with these batteries.

    I do aplogize for the rant... but felt it necessary.
  8. _cy_

    _cy_ Long timer

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    please quit reading things into something I never posted. what I did post is still dead on the money. if it will make you feel better, please assume I'm not implying anything other than what I specifically post.

    Never have I stated final form factor is smaller with prismatic cells vs cylindrical cells on a motorcycle battery. final form factor is determined by each mfg. for instance Prismatic cells require support to keep pouches from twisting. this adds extra bulk.

    it takes a total of four large prismatic cells to make up a 20 amp hour (actual) battery. it'd take 32 A123 cells to make a 20 amp hour battery. which final form factor would be smaller? ... the answer is ... it depends on how the mfg decides to put it together and what type of enclosure will be used.

    Prismatic cells don't have the bulk, metallic cans take up. they also don't have the advantage metallic can provides, like ease of spot welding beefy contact strips used to make up multi cell batteries. this is a major reason why cylindrical cells survive continuous high discharge tests Joel has been doing. while prismatic cells fail at those same high rates.

    where I was having issues was ... no one that I'm aware of cranks their engine for 30 continuous seconds drawing 200 amps for the entire 30 seconds. cylindrical cell's beefy connectors survives that type of tests with no problems. vs prismatic cell's lack of metallic support structure results in internal connectors that are not as robust will overheat and fail.

    that doesn't mean prismatic cells cannot do the job of starting a motorcycle. which normally only requires 200amp (max continous) loads for 5-6 seconds. if a prismatic cell battery can repeatedly deliver starting current of 200amp for 5-6 seconds for say 20+ cycles one right after another. but catastrophically fails the 30 seconds continuous 200amp tests by melting and smoking.

    what I've been doing is pointing out advantages and weaknesses of cylindrical vs prismatic batteries. each has both.

    for instance when cylindrical cell batteries are wired in parallel. all cells wired in parallel will self balance since all cells will be kept at same voltage. disadvantage is if one cell shorts out... rest of cells wired in parallel will all discharge into the shorted out cell.

    the more cells involved in building a battery... higher the chance of cells going out of balance as batteries ages. without question cylindrical cells have an advantage of being able to survive higher discharge currents due to more robust construction.

    another advantage cylindrical cells enjoy is volume. advances takes place first with 26650 cells. there's only about a dozen lithium battery mfg in the world. with hundreds of re-labelers. yes there are lots of junk out there. but what makes you think A123 is the only mfg out there that makes outstanding 26650 cells?

    don't get me wrong... it's generally acknowledged that A123 26650 cells out performs all other 26650 cells and costs more. but that may not stay that way forever. witness lithium power tool mfg move from A123 to other brands of 26650 cells. I've noticed no lack of performance from my brand new Milwaukee lithium powered tools that no longer uses A123 brand cells.

    lithium ion battery advancements is one of fastest evolving sciences anywhere. A123 is not the only mfg that's investing in R&D. what's more likely to happen is advances will take place in one of our universities. then that technology will be given away to the world for next to free. where do you think the technology A123 uses originally came from?

    now what do you see that's biased in what I've been posting?
  9. _cy_

    _cy_ Long timer

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    please excuse the commercial msg, but video does contain bits of information about cylindrical vs prismatic

    <iframe src="http://www.youtube.com/embed/zScUKZwTPHw" allowfullscreen="" width="560" frameborder="0" height="315"></iframe>
  10. DiabloADV

    DiabloADV Semi-Occasional

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    Did this question ever get answered?
  11. _cy_

    _cy_ Long timer

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    you'll have to ask EnduroLast ...


  12. DiabloADV

    DiabloADV Semi-Occasional

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    OK -- I asked Euromotoelectrics...

    The answer is non-specific. They had one customer that installed an Endurlast charging system in a Ducati, while also installing a Shorai at the same time. The customer had problems, so Euromotoelectric won't warranty their system with anything but conventional batteries. So, there seems to be nothing specific...simply a preventative measure on the vendor's part. Which I can understand...
  13. _cy_

    _cy_ Long timer

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    correct me if I'm wrong... but here's the basics

    all alternators rotates a magnet through or around the stator (HD). then uses a diode rectifier to convert the AC output to DC.

    there's two different ways to generate the magnetic forces needed within a rotor. one type uses permanent magnets. other uses an electromagnet.

    both types uses a voltage regulator. but they work entirely different. each has advantages and disadvantages.

    permanent magnet alternators pretty much operate at full output all the time. excess current is shunted to ground in the form of heat. advantage is slightly higher efficiency. can still charge up battery in-spite of low RPM usage. disadvantage loss of HP generating excess current which ends up as heat. which can overheat area near voltage regulator.

    electromagnet alternators varies the current delivered to the electromagnet rotor. voltage regulator works by changing current sent to electromagnetic rotor. disadvantage is this process uses 3-4 amps. output also varies with RPM. one could easily run down a battery if engine is not rev'd high enough. advantage is no wasted HP generating excess watts.

    with all that out of the way... let's get to why I posted above..

    what happens should a voltage regulator fail?

    if a voltage regulator on electromagnet alternator should fail .. usual result is no output. very rarely does an internal short result in full output.

    if a voltage regulator should fail on a permanent magnet alternator. output could continue at full output or fail altogether.

    LiFePO4 motorcycle batteries are either not regulated and/or regulated at very low values after full charge is reached. this means failure of a voltage regulator on a permanent magnet is more likely to result in overcharging a LiFePO4 battery or any other battery to failure.

    so if given a choice on Airheads of which high performance alternator to go with.... I'd pick the electromagnet alternator version every time. unfortunately on late model motorcycles you don't get a choice.
  14. JoelWisman

    JoelWisman Long timer

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    Depending on priorities...

    The only technical part I disagree with above is where the heat ends up.

    There are 3 fairly different kinds of voltage regulator for PM alternators.

    1: SCR shunt. This regulator contains diodes to rectify the AC on the back side and 1 to 3 SCRs to shunt excess current to ground. The diodes and SCRs do have some resistance and therefore do heat up when there is a significant excess charging capacity from the alternator, EG at high RPM with few electrical loads switched on. HOWEVER, the greatest resistance in the system is the stator and that is where the great majority of heat is created.

    2: MOSFET shunt. This type of regulator is exactly the same as above except for the use of MOSFETs in place of the SCRs above. MOSFETS have extremely low resistance and very little switching heat so the only appreciable heat generated is from the rectifying diodes themselves. Note, a wound rotor alternator like an airhead has, has rectifying diodes as well.

    3: series PM regulators. This type of regulator uses MOSFETs to switch the stator open to regulate voltage and creates no greater heat then a wound rotor alternator, but like a wound rotor alternator is not quite as efficient as a shunt regulated alternator owing to losses flowing in series through the MOSFETs



    NOW, lets consider the components in each common system (series PMs are uncommon)


    WOUND ROTOR ALTERNATORS like an airhead has.
    1: a wound rotor that can and does fail.
    2: sliprings to transmit power to the wound rotor. These wear out or can short.
    3: 2 brushes both of which wear out and can also break or burn up or frequently melt their holders and jam.
    4: Separate bearings for the rotor on many applications including some modern BMW's such as the R1200GS or K bikes. Oh yes these bearings fail.
    5: A belt driving the alternator if separate which of course wears out and will break instantly if it picks up the right rock.
    6: air cooling which can plug.
    7: A stator which of course can fail.
    8: A diode bridge to rectify the AC which can be reliable but if oe is most unreliable on BMW's
    9: A voltage regulating circuit that controls current to the wound rotor.
    10: A circuit to energize and de-energize the voltage regulating circuit.

    Practical experience, I dealt with airheads that had a failure in some part of this charging system causing the bike to cease charging and strand the rider at least weekly which is significant considering there aren't a great deal of air heads on the road.


    PM ALTERNATORS
    1: A flywheel with permanent magnets that never breaks. It needn't be included in this list because in 24 years I have honestly never seen one fail.
    2: A stator. Some are designed well, some aren't. The stator in the BMW F800GS fails regularly between 20k and 50k miles, but has since been redesigned. Most stators are VERY reliable with a few exceptions of poorly designed units.
    3: A single component that does the rectification and voltage regulation and is nearly universally adaptable from one bike to the next if capacity is at all similar though there is nothing wrong with using one that has a higher capacity. It is usually the diodes that go and usually because battery terminals were left loose in which case the system fails open and voltage goes low. On rare occasion the voltage does go high just the same as it can with a wound rotor alternator.

    Thats it for the PM alternator, 3 components 1 of which never fails. The remaining 2 components will fit as spares under the seat and weigh less then 3 pounds.

    The wound rotor alternator has between 4 and 7 more components all of which have a high incidence of failure and weighs about 4x to cary as spares to say nothing of the increased difficulty in diagnosis and field repair.

    On an adventure, i'd go with a PM alternator every time.
  15. DiabloADV

    DiabloADV Semi-Occasional

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    Is there such a thing as a PM alternator for an airhead?

    My CL175 has one and it works pretty good. I put a new reg/rec on it and it pumps out the volts and will idle with all the lights on and my GPS plugged in. And that's with a capacitor; no battery.
  16. Anorak

    Anorak Woolf Barnato

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    Yes, this, it's based on the Ducati alternator. I worked as a mechanic at a BMW dealer. I have a bunch of failed BMW rotors and a few diode boards from that job. I was also a mechanic for a Ducati dealer. The only issues I saw on their charging systems were poor connections between the alternator and regulator/rectifier on older models causing high resistance and poor charging. We'd replace the connector with crimped connectors or solder and that took care of the issue. I did see a bad regulator on a brand new 1098 once. It didn't charge.
  17. DiabloADV

    DiabloADV Semi-Occasional

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    Hmmm...do I get the alternator or the ignition kit? Don't think I could spring for both.
  18. Anorak

    Anorak Woolf Barnato

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    I'd say the ignition is more reliable than the alternator.
  19. DiabloADV

    DiabloADV Semi-Occasional

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    That's what I keep hearing. But the ignition makes it run better!

    I don't know what to do...
  20. _cy_

    _cy_ Long timer

    Joined:
    Sep 25, 2011
    Oddometer:
    6,468
    Location:
    Tulsa, Oklahoma
    along with many others, have consider differences between PM and EM high performance alternators for airheads. in context of prepping a RTW bike.

    currently there's only one source each in the world for PM high performance alternators and EM high performance alternator kits for airheads.

    difference is EM high performance alternators can use stock parts in a pinch. voltage regulators are the same. stock diode boards, rotors and stators can be used in a pinch. performance will go back to stock. but you will be back on the road.

    would not want to be broken down in say Siberia with only one source in the world that's got parts for your downed alternator.

    for EM alternators, spare brushes and voltage regulators can be easily carried. stator and rotor can be rewound locally. brushes fits most bosh alternators. voltage regulator can be used from most Volkswagen.

    naturally my choice, an 450 watt EM alternator is installed on R80G/S.

    for PM alternators, as joel pointed out alternative PM alternator voltage regulator can be rewired to work. burnt up stators can rewound too.

    both are valid choices, so long as high performance versions of either PM or EM alternators kits are used on Airheads.

    keep in mind, I'm the type person that will yank out out electronic ignition bean can, ICU, 1.5 ohm coil and replacing with points bean can with matching 3 ohm high performance coil on R80G/S.