bit of an odd one. New battery (less than a year?). When fully charged shows 12.7V engine off, 14.3 at tickover, 2k and 5k revs. Slight drop when lights on, but not much. Leave the bike for a week in the garage, drops to 12.2V and won't turn the engine. No alarm/immobiliser fitted, only obvious electrical gremlin is a neutral light that shows a dim glow through all gears (bright when in neutral) and a dip beam that occasionally doesn't light up. All the rest runs fine and engine pulls well.....although has the occasional miss fire at low revs when manoeuvring An ideas as to what could be causing it to loose charge in a week?
Youre charge voltage looks about right, I would suspect a bad connection somewhere, especially if you have current leakage on the neutral light etc. Rectifier seems ok if its charging up the battery.
Thanks - rectifier running ok so charge is good.......but a bad connection is interesting as charge seems to "leak" away when not in use. I'm assuming all circuits are switched via the ignition switch and are only live when this is on (or in "park" position)......not sure where to start to trace a bad connection though.
Yeah, its not the easiest to deal with. See what the current draw is from battery when ignitions off for a start. It could be a number of things, check all your wires! Earths are tight etc
Try disconnecting the battery for a week and then check to see if it holds its charge, that will eliminate a battery problem, then start looking for an electrical drain. Steve
Steve, good call. Upside - I'll know if it's the battery.....down side, it's a week on the Beemer (1150R)......which is not as "urgent" in its running characteristics as the Duc....
Nothing extra been fitted, that isn't switched off ignition? Even a USB socket will constantly drain a small amount with nothing plugged into it. Sent from my iPhone using Tapatalk
With everything off you can measure any draw on the battery with a multimeter. The neutral light thing might suggest a bad earth.
Charge the battery again; connect the positive terminal; then use a small 12 V bulb connected between the negative terminal and the negative cable.....if it lights, there's a problem. A fully charged battery should read anywhere between 13 - 14 volts as soon as it comes off the charger. In a matter of less than an hour, it should show about 12.8 volts..........over a week with no use expect it to drop to about 12.5 - 12.6 volts and there it should stay for say, two to three weeks. A fully charged conventional lead acid battery without any use will probably drop by 0.1% each day. Also, the Electrex RR51 reg/rec (if fitted) is rumoured to have a small current draw even when all things are switched off.......I don't know if that is true or not.........It doesn't seem to happen with mine.
Dropped from 12.7v to 12.4v overnight, whilst still on bike. Battery now off bike and will recharge and see if it looses charge on its own. If it does, at least it isolates the battery as an issue.....if not, I guess it's then a matter of tracking down bad connections........starting with the errant neutral light. No other devices run when ignition off (is no satnav etc). Only flying lead off battery is the optimate thingy.
Type of battery and make? Yuasa appear to not recommend use of Optimate on conventional lead acid batteries. I always use a conventional charger and use lead acid batteries.........plus I was told years ago by an auto electrician to always disconnect the battery when charging and I still do that. But whenever I see posts about battery trouble it nearly always seems to involve an Optimate.
Al, the optimate thing seems quite true but invariably the issues are raised in posts from people who leave their bike with an optimate connected and on all the time, this should be avoided as it hides developing faults in the battery and the rectifier and is a fast way to a break down at the side of the road. If you use an optimate as a charger/conditioner for a few hours or a couple of days at a time and disconnect it after use I don't think there are any issues. Also all AGM batteries are still lead acid. Steve, I too have had a boil from an electrex rr failing at >19v on a 748 (a melted and leaking battery case was the result, you may remember my posts on Ducatisti about it) and also now use the Shindenghen ones with yellow stator wire connector removed and yellow wires through jointed and insulated, they only cost a few quid more and are fully reliable if the connector issues are eliminated. The OPs battery is shot or the rr is otwo, for the battery just get a new AGM one, fill it, charge it overnight before fitting it and never leave it to go less than 50% charge particularly over winter. It is common for a new battery left uncharged in an unheated garage over one winter to die, sub zero temperatures on partially charged batteries kills them better than anything else. This means connecting a charger or optimate every 2-4 weeks depending on the season. You can get >7 years out of a good quality one if it is looked after so don't skimp on a £10 cheaper one, recommend a Yuasa every time (most used OEM vehicle battery supplier across the world)and ignore any battery seller that claims Gel and AGM in the same battery advert. For owners of bikes with a dash voltage readout like 999/749, that does not show the battery voltage at the battery terminals so the generally lower rest voltage readings it displays will be below 12.7v.
When I first got my SS the battery that was fitted was a Rob Hunter 'Yuasa lookalike' conventional lead acid one. It appeared to be at least 7 years old when it started to play up, although I didn't realise it was playing up. Up until then I had only ever had to top it up twice and charge it twice. I have an RR51 reg/rec fitted. When I fitted a battery monitor, it used to show overcharging at certain revs (around 2500 - 3000) so I made sure I ran with headlights on which stopped the overcharge light. When the starter sprag gave up, I noticed the battery wasn't holding a charge and it seemed as though one cell had dies and another was on the way out.........It would drop from 13v to 12.2 / 12.3v within 12 hours. It seemed the weak battery had caused the sprag not to grip properly and the spring in the sprag was well chewed up. Fitted a new sprag and a new Yuasa conventional battery...........and all now OK. But it doesn't show an overcharge now, so I can only assume it was previously showing an overcharge because; 1) It was a cheap battery; 2) By the time it packed up it was 9 years old; 3) or dead cells can cause an overcharge reading.
After two failed electrex regs I fitted the shindengen unit three years ago and have no problems whatever. Steve
BS battery fitted when I bought the bike - less than a year old. Using Lidl charger ((quality piece of kit that has kept my Beemers battery in perfect condition for the last 5 years...so problem not cHarger.........not using optimate but flying leads similar). Charged battery off bike today....now showing 12.9v (was 12.7 on bike).....and finishes cycle ....ie it doesn't continue to put battery through recovery cycle when charged off bike. Leads me to think there is a dodgy connection somewhere as all else is fine (inc RR unit as charge voltage is within limits). Will see how much is lost in coming week but logic suggests dodgy connection somewhere.......just got to find out where :-(
Plus one for Yuasa AGM and plus one for not leaving the charger connected. Team the Yuasa up with a cable kit from @Exige and you should get urgent, reliable cranking and starting that will keep your sprag clutch very happy (Underlying faults excepted of course )
Fitted with cable kit. Starts very well when battery ok! Looks like the battery is knackered .......dropped from 12.9 to 12.5v on the bench........if it caries on at this rate it will be well below 12 by tomorrow am. Fitted with a BS battery.......never heard of them.....Chinese?
