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Another battery question

Discussion in 'Maintenance and Servicing' at netrider.net.au started by tongnk, Oct 31, 2015.

  1. So last time I posted the VTR250 had run out of battery since I kept starting and stopping it again. Got a battery charger, charged it up and it went great.

    Just rode tonight and the battery died again. Wasn't doing a start/stop this time but was riding around the suburb at relatively low speeds (20-60kms). Stalled once and it was then that the battery died. Luckily there was a hill I could push the bike up and after a couple of attempts was able to start it with a push start.

    Battery is currently charging at home again but wondering if this is an indicator that I need a new battery? The only other thing I can think is that I was using the hi beam whilst riding. Not quite sure if this is the norm (assuming this is the case as lo-beam is on by default?) and maybe this was the case of draining the battery?
  2. A healthy battery and charging system shouldn't have any trouble at all running your lights. Change your battery.
    • Agree Agree x 1
  3. check the voltage at the battery while the bike is running. if less than 12V, it is not being charged
  4. Also make sure you bench charger not over-charging.

    A lot of the cheaper units don't have the internal smarts to power down once the battery has reached full charge and they keep putting more juice in which will eventually over-cook the battery.
  5. Not sure if the one I have is cheap, got it from MCAS (http://www.mcas.com.au/motorcycle-parts-road-batteries/xtech-12-volt-battery-charger). It has a red/green light and I think it stopped itself from charging when it hit full last time?
  6. Letting your battery run flat kills it a little every time. The flatter you get it the worse it gets. It might simply be time for a new battery.
  7. The two most reliable battery killers are overcharging and leaving a battery completely flat in storage, followed by lack of maintenance.

    Where you do not have a maintenance free battery, ensure that the electrolyte is always at the correct level (watch this in the Summer where high temperatures will cause some evaporation, and otherwise, watch the level. Check at least every time you change oil.

    Uncharacteristic sudden drops in level and "gassing" (lots of bubbles) are often a sign your bikes rectifier/regulator is overcharging it. It will die quickly (hours), where this occurs. A sign is overly bright lights. If you spot this quickly, (and it's quite noticeable if you ride much at night) you can avoid the expense of a battery in addition to a replacement reg/rec unit. Charging voltages of much over 14 or 15 volts is a giveaway.

    Batteries do not last forever, and you generally get what you pay for both in batteries and chargers. My favourite maintenance chargers are C-Tec. They come with accessory plugs so you can connect the charger easily to the battery when the bike is to sit for a long time (like months). Maintenance free batteries are a favourite of mine, reducing maintenance to only ensuring that the terminals are clean and secure.

    The short response, Tongnk is that it looks like your battery is due for replacement, but don't discount the reasons it might be if it is not years old.
  8. I had two or three of these when I was in Canberra and they worked great for a couple of years, moved down to Tassie and they all died within 12 months but I believe the issue was the mains voltage down here, it gets up pretty high, they just recently re-tapped the street transformer - I was reading close to 260v. They are not a bad charger battery/tender and do trickle charge once full charge is reached, but they are very basic and don't have the multistep process of reviving poor batteries that the more expensive chargers have.

    I'm with jstava and have a couple of CTEK's, a smaller (cheaper) XS0.8 for the bike and a larger MXS5.0 TEST & CHARGE for general duty work. You can sometimes get the CTEKs on special at the local car parts stores, they all stock them.
  9. Ok thanks everyone. Looks like it's time to look for a new battery. Any thoughts on specific batteries or should I just get the same one as the current one (YTZ7-S from Yuasa I believe)?
  10. Before you change the battery, check the voltage of the battery at ~5000rpm after it's been charged. It should be between 14V and 16V. If it is less, the charging system is clearly the culprit and you may not need a new battery at all (it will just go flat as this did after some riding).

    A simple check is also to check the brightness of the low beam while at off, then at idle, then at ~5000rpm. It should be relatively dim while off and at idle, but progressively brighter as revs go up. If it stays dim, charging system is at fault.
    • Agree Agree x 2
  11. Thanks guy. Looks like I need to get myself a multimeter and check it out.

    I did try the brightness thing whilst the bike was in neutral (is this the right way to test it?) and the low beam didn't exactly change brightness (I'll double check as I think I did it on the weekend).

    Another question I had was that everything was to be working as per normal does the rpm I ride at affect how much it charges? I'm still probably barely hitting the 3-4k band of RPM as I'm still practising at relatively low speeds (hitting maybe 60 once in a while)...
  12. Yes the rpm will affect the alternator output. At idle it might just be pushing out enough to keep the bike from using the battery - depends on what you have running; e.g. if all lights and heated grips are on you are probably drawing some power from the battery at idle, the voltage level would also be low (might even be as low as 11.5 to 12v if heavily loaded. As you increase revs the alternator can supply more current, there is also a corresponding increase in the voltage level. Depending on the bike at around 4000 to 5000 rpm the alternator has reached max and won't supply any more current.

    So your riding habits should not present any problems to the charging circuit if everything is working correctly, the alternator would be pushing enough current to run the bike and charge the battery. I'd expect to see the voltage reading topping no more than 14.5v at your 3-4k mark, maybe a fraction lower.
  13. Can't go wrong with a stocker, but alternatively you can get a lithium battery for about $100-110. Weighs less, cranks harder, doesn't discharge as fast when the bike's off. Google "SSB LFP5L-BS".
  14. I'd be suprised if an alternator wasn't charging just above idle. Old generators were bad and, yes, on smaller capacity bikes it can be worse, but it should be well and truelly charing by 3.5k.

    As mentioned above it should be showing about 14.3V when it is charging at some revs. If it's as high as 16 or as low as 12 when charging, then your regulator could be on the way out.

    Most likely it's the battery, however. If it isn't already, switch to a modern "sealed" style battery, rather than the wet type typically found in bikes from the 90s or earlier. The sealed ones handle sitting aroudn between rides a lot better, whereas the "wet" style ones only last about a year if you are not riding a couple of times a week, every week.
  15. So just checked the voltage.

    Got 12.8 with bike turned off. I then turned it on and put on high beam to 5000rpm and only hit 13.3. Does this mean that it's the charging that is the issue?

    Definitely not got an older battery (it's this one: SSB PowerSport > Products > Product List). I've ridden it about 2 times since it went flat and I recharged and haven't had problems but that said I haven't stalled or had to use the start motor more than at the beginning. Do you guys think it's the battery needing replacement or would it be better I take it into a mechanic?
  16. #16 Returned, Nov 7, 2015
    Last edited: Nov 7, 2015

    Edited: ********* see next post **********
    • Funny Funny x 1

  17. ************* If this is the right workshop manual have a look at section 16 Battery and Charging system . 13.3 at 5000rpm looks a bit low compared with manual. Manual gives you some testing procedures to isolate fault ****************