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Flat battery - car charger?

Discussion in 'Bling and Appearance' at netrider.net.au started by alleyway, Jun 29, 2009.

  1. Hey guys,

    Went to go for a ride yesterday only to discover that my battery was flat. Ended up using a normal 12V chargor (which I've also used for the car) on the battery. Just read an article which says using a car charger is really bad for a bike's battery....anyone know whether this is actually the case? Started up the bike after charging it and it worked but is there any way to know whether I've done permanent damage to the battery (or anything else)?

    By the way the bike is a VTR250.

  2. If you charge the battery with the full power of a car chrager you can boil the acid and kill the battery.

    Charge the battery on 12v trickle charge if your charger has that.
  3. A car charger on a low setting will be fine.
    Best way to keep a battery charged is to use it :wink:

    Run a multi metre across the terminals with the bike off (sitting for a while) and if it reads 13v + it will be ok otherwise go battery shopping especially if you dont regularly ride.
  4. If it's a lead-acid battery, I don't see why there would be a problem. Lead-acid is lead-acid, just that the motorcycle ones are smaller. (Though smaller batteries must be charged at a slower rate)

    My Swallow 2 charger recharged my Tiger's sealed lead-acid battery recently without catching fire or exploding, though it is particularly careful and finicky with batteries.

    Without seeing the article in question, I can only assume they were talking about drycell batteries and gel cell batteries, which do require different charging techniques to lead-acid batteries.
  5. This was one of the articles:


    Not entirely sure what kind of battery the VTR takes. If I had killed the battery would the bike still start up or is it possible that I've done something bad to the battery (or something else) that will only show up later (when I'm least expecting it!!)

    Thanks again
  6. Some car chargers are capable of adjusting to the capacity of the battery. Did you any chance notice what rate it was charging at on the dial? (if it has one).
    Some will charger a small battery slowly (say 1-2A), but others will hit it with the full 5A+ which is not good for the long term life of the battery.
    In most cases it's cheaper to buy a suitable charger than it is to replace the battery more often.
  7. car charger mate, the o is a fair distance away from the e on the keyboard :LOL: :LOL:
  8. good point - Monday morning! I use the "o" chargor a lot in my line of work so will blame that! :oops:
  9. It also depends on the battery.

    Mine says to charge at 5A rapid for an hour or trickle overnight.

    My car recharger operates at 4A high charge - so I figure it will be OK
  10. Rather than a charger, I like to use (on car and bike) a portable battery jump starter, then just take it for a ride/drive to recharge. You can pick them up for $50-$100, leave in the garage or boot of car. Saves a lot of mucking around trying to jump start from another vehicle or wait for roadside assistance etc.
  11. Car batteries come in all shapes and sizes, from what you'd find in a mini up to high CCA deep cycle jobs.

    It should be fine.
  12. just jump start her and ride her for a bit... it;ll be right
  13. Most of the cheap car battery chargers won't put out more than 2 amps anyway, even it they say such things as 5Amps Max! A lot will then say something like 2amps RMS in fine print. 2 amps will be fine on a lead acid bike battery.