Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

Featured Battery recharger or new battery?

Discussion in 'Maintenance and Servicing' started by Salad Cycle, May 1, 2015.

  1. My 12 volt 6 amp motobatt battery went flat, left the keys in the ignition.

    New battery costs $94.

    I have seen many prices for battery chargers.

    Is it more economical to buy battery charger or battery?
  2. I guess that depends on how many batteries you are going to flatten making the same mistake.

    Personally, battery charger FTW.
  3. you can only "flatten" the battery so many times before it becomes useless. If you are going to make a habit of leaving your keys in the ignition, no battery charger is going to save you.
    If this is the first time though, there is every chance a charger can save this battery. I use a CTEK XS0.8 (from memory) and because I don't ride as often as I should I leave it connected when the bike isn't in use
    • Like Like x 2
    • Agree Agree x 1
  4. Both which will mean the battery life will last longer
  5. Personally I think everyone should own a decent battery charger.
    The more vehicles you own the more beneficial and you'd be amazed how many "dead" batteries can be bought back to fully operational.
    Also if you haven't used your bike in a couple weeks, it's always a good idea to hook a charger up and top up the battery, a battery that is kept charged will last a lot longer.
    • Agree Agree x 2
  6. ^^ Agree with the other comments but the battery charger will be of no use whatsoever if your battery is below 10.5V (I suggest adding a multimeter to your shopping list). If it's below this you can rescue a battery (sometimes) but not using a charger as the only method.
  7. I am pretty forgetful. I went though at least 5 batteries on my last bike because the ignition was below the seat and out of sight.

    $65 for this CTEK XS0.8 sounds better than $94.

    Thanks for the replies.
    • Like Like x 1

  8. Maintenance chargers like the CTEK XS0.8 will usually not be able to lift a flat battery to charge level. They will see it as a faulty battery because the voltage is too low. You may need a normal charger to get it back to a voltage where the Ctek can then maintain the charge.
    • Informative Informative x 1
  9. Only true with modern, wanky "smart" chargers. An old fashioned buzz box with just a transformer and rectifier inside it and none of the control electronics will bring anything back from the dead, at least temporarily.

    I've never used anything else for charging (got a couple of $20 solar panels for maintaining) and my batteries last a long time. I've yet to fry my vehicles' electrics too.

    Edit: Actually, if you're forgetful, maybe it's not such a good idea. You do have to remember to switch off and disconnect before the battery boils dry.
    • Agree Agree x 2
    • Like Like x 1
  10. You may also want to switch your bike off using the ignition switch. Seen too many people use kill switch and leave ignition on.
    • Agree Agree x 1
  11. One thing lead-acid batteries do not like is deep discharge, it causes permanent chemical changes which the normal discharge-charge cycle can't reverse. You can recharge them but the capacity is reduced. Like putting a whooping great dent in your petrol tank. You can still put petrol in, just not as much. Go low enough and the life is shortened. It might work fine for another 6 months & then die without warning. Me, I'd buy a new battery and maybe later a charger. I was off my bike for 40 days & the battery was dead, not enough to turn it over just solenoid chatter. Smart charger I got from ALDI brought it back, but a couple of weeks later on a hot day it gave up the ghost and died idling in traffic. I'm relying on my ability to roll start until I get a new battery.
    • Agree Agree x 2
  12. you sure about that? I've recharged flat batteries (but not sure how flat).
  13. Technically speaking a 12Vbattery is flat at 11.9V. You can piggy back the battery to a fully charged battery of similar capacity and leave it for several hours while the voltage averages across them both before hooking them up to a decent (yes, new wanky) charger. If I was buying s CTEK, I'd go the 5.0, but then i'd go bigger and get the one with power supply feature.
  14. Whilst I'm aware of the damage that deep discharge will do to a battery, I've done all sorts of horrible shit* to batteries and have yet to have one fail completely without warning. A single flattening certainly shouldn't stuff a battery beyond redemption and, in my experience, you can get away with two or three at least before you really start to notice any loss of capacity. Mind you, pretty much all the vehicles concerned have been in everyday use where an inability to hold charge for a month isn't terribly important, and most have been able to fire on the first or second compression stroke so I've not generally needed the ability to churn the engine over for minutes at a time.

    *Horrible shit meaning rapid deep discharge (lights left on), slow deep discharge (vehicle left standing),boiling dry followed by refilling with tap water and then zapping with old fashioned charger (rec-reg failure), charging a car battery at 30+ amps (possibly more but the ammeter hit the stop), connecting the wrong way round and doubtless various other crimes against prepackaged electricity that I now forget.
  15. Patb is right it will be really old abused battery that will kark it. And after a quick deep discharge. Have had a couple that have gone on for months after much abuse, but have failed to nothing but solenoid click. Likely dodgy wiring involved there. My situation involved an underrated alternator that doesn't provide enough power to the electrics at idle, with voltage dropping to 11.2v. Daily commute kept it fine. No use for 40 days and hot day with rad. Fan cutting in a lot was obviously too much.

    If the OP could get some lazy turn overs then it's probably fine. Suck it and see.

    I too have abused too many poor batteries. Had an ALFA that had green insulation on the positive lead to the battery! Wrapped it in red tape after too many nasty reminders. Bosch must have fitted a reverse polarity diode to its L-Jet ECU.
    • Agree Agree x 1
  16. I'd add that I'm not actually recommending indulging in electrical abuse. I'm just pointing out that you can often get away with stuff that conventional wisdom says you can't. And sometimes you need to get out of a hole and accepted best practice isn't an option for whatever reason.
  17. Get one of them new fangled jump starters. Let the alternator do the charging once it's started. If that isn't effective, what pat said.
  18. Well, you guys must have put the moz on me. First ever flat battery on a bike by deep discharge as my plans for going out again changed and I left the key in. Bike sat for about 4 hours before I went to put it away and realised my mistake. Pushed it into the shed, whacked the battery charger on it and left it. Just checked it this morning and it started first time no problems.
  19. MXS5 is still ok for bike batts, but for the MXS7, the minimum "recommended" capacity is 14Ah, so charge rate may be a bit high.
    maybe ok for initial reviving, but my MXS15 couldn't bring back a bike batt after it dropped a couple of electrodes :D
  20. I could be mistaken as it's been 9 months since I looked at it but doesn't the MXS7 have a bike setting? I'd get the 5 if that isn't the case...