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Winter and my Battery

Winter and my Battery

  1. cjvfr

    This is the time of year that batteries tend to die. Oil is more gluggy, engines slower to fire and...
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  1. And no coincidence my battery in the Super Duke died yesterday morning after pulling up 40 mins into a ride. Managed to click it up a few gears and man handle it enough on the side of Wynnum Rd in Brisbane to maype put it into a sweet spot of the stroke and i got it to turn over just enough to fire up and get me home. The battery is still holding a charge but it has no cranking power left in it. Just need to find a Yuasa distributor tomorrow and be sorted again. Informative peice of literature for those that need it, nice one. :)

    • Like Like x 2
  2. In this weather, (in fact most of the time), mines tethered to a small 2A smart charger with trickle mode. Well worth the investment.

    Nothing worse than heading out, or even worse, heading back, and bike says no.
    • Agree Agree x 2
  3. This is on a trickle when it needs it as well, but age was the contributing factor on this battery i would guess. Good idea for others who may not use them, especially if you wire in a quick connect harness it makes it so easy.
    • Agree Agree x 3
    • Like Like x 1
  4. Agree a maintenance charger is good value particularly if your riding is commuting short distances. The battery will not recover from the start if you only ride short start stop type rides. A maintenance charger will give you a much longer life out of your battery as well by maintaining it at optimum charge level.
  5. Today the CCA rating needs to be replace by the FFCA rating ( F'n Freezing Cranking Amps)
    • Funny Funny x 5
  6. My Reg/Rec literally went 'pop' under the seat a couple of weeks ago. I noted it but forgot to check the charging later on, and sure enough two days later the battery was too low to start the bike.
    You don't usually get that much of a warning, but looking back I had thought that the headlight was a little dim and yellow rather than bright white.

    Oh, for amateurs like me - if your voltmeter has a third port marker '10amp' DO NOT put the positive lead into it to check the battery unless you want to see the plastic lead burn and the copper wire melt :banghead:
    • Like Like x 1
  7. Great post. I stumbled on this on youtube and wonder if somewhere in the future, bikes will have big capacitors to get the crank going.

  8. Hmm, not to sure about that. Cant really believe that those CAPs alone would even get the starter to turn, let alone crank the flywheel?
  9. #10 oldcorollas, Jul 13, 2015
    Last edited by a moderator: Feb 19, 2016
    certainly could, they have very high discharge rates, so can dump all their power in seconds.
    but they have other drawbacks, like,, dumping all their power in seconds :D
    seriously though, high self-discharge rate, low Ah/kg, and high cost are the main issues...

    say you had a 1kw starter, and crank for 3 seconds, that's only 250 amp-seconds (or 4.2 amp-minutes, 0.07Ah)

    1 Farad = 1 Coulomb per Volt
    1 Coulomb = 1 Amp-Second

    say you have supercaps at 2.5V, run 5 to get 12.5V, and set 10V as lowest during starting (so half a volt drop each)
    1farad cap = 0.5amp/second (for that 0.5V drop)
    for 250 amp-seconds, you'd need something like 500 farads?,

    that dude has 350farads per cap in that pack, but running 6 so should have a max of 15V,
    he had 14.2 before starting, so if it drops to 10V, he'd get 0.7V drop per cap = 0.7amp-seconds per farad = 245 amp seconds = ok for 1 start

    if it didn't start first time, he'd be stuffed :D (and it might have dropped the 0.8V total in between charging time and hooking to car :p )

    or I might have that wrong??
    6 in series would be 58 farads? (1/Ct = 1/Ca + 1/Cb etc?)

    anyway, stuck the trickle charger on to be sure.. has been chilly last few days :)
  10. STICKY
    • Agree Agree x 1
  11. That seems to make sense, though I've been out of the calculations for some time.
    My thought was that the problem with the battery is the internal resistance that limits the amount of power to the starter. So the capacitors could charge slowly but discharge quick.
    Aside: did you ever see myth busters where the disable the remote control on a bomb by spraying it with liquid nitrogen.
    Another fault is when there's a bad connection in the starter circuit so even though the battery is fully charged, it can't get enough current to the starter.
  12. Yes that one catches a lot of newbies. The lights come on with the ignition so the battery looks OK. But when you draw heavy current for the starter motor the high resistance joint drops voltage across it and limits the start current.