Electrical Issue!

[MrGrumpy]

Electrical issues on my 2009 Tmax....
I normally leave the scoots on a trickle battery charger. I was going down South last week, but when I connected my battery charger to the Tmax, I got flashing error lights on the charger, indicating a Short Circuit. I was on the way out, so couldn't do anything then, so left everything unconnected, assuming my very cheap battery charger had failed.
Come back from the South today, and the Tmax battery is totally, utterly dead - not a hint of life! Yet if I connect my charger, it now appears to be charging.

Anyone any idea what's going on? Has the Tmax battery failed??

[Funkycowie]

If you haven't changed the battery since you bought it off me, then the battery in there will be about 6 years old now and i think it was only a motobatt one, it may have died. That could be because of other things though like the stator, etc.

[Deleted User 18446]

Continually trickle isn't good for batteries long term they need to cycle a bit like in normal use .

[abitmad]

Continually trickle isn't good for batteries long term they need to cycle a bit like in normal use .

That's one of those urban myths amongst some bikers. Lead acid battery chemistry means that the longest life is obtained by keeping it at full charge, either by riding the bike or by keeping it on a smart charger when not. I presume when you refer to "trickle" you really mean a smart charger like an Optimate or CTEK. I know these are often described as trickle chargers but it's wrong. True trickle charges are very old tech devices that were employed merely to bring a battery up to charge. They certainly could not be left on indefinitely and you hardly see them any more. Smart chargers monitor the current and voltage according to the battery status and can be left on indefinitely, precisely because they are "smart". They can't overcharge or otherwise do any damage, assuming of course they are not faulty.

I know there are stories circulating of how someone's mate fried his battery with an Optimate. Either it's made up or even if true, it was extemely unlikely to be the charger at fault. Almost certainly the battery was knackered already or something else was wrong with the bike's charging circuit, alternator or reg/rec causing it to overcharge. The chances of the charger ruining a battery are so vanishingly small as to be ignored.

A couple of points though. Grumpy said he was using a very cheap charger. In my view one should stick with the leading brands of smart charger as above. Secondly after six years, the battery is likely finished as FunkyCowie suggests. Even a smart charger can't keep one going forever.

[MrGrumpy]

Yes, I haven't changed the battery since I bought it, so it is a fair age, though I thought it should last if kept charged properly. Maybe it was getting a bit marginal and it was only my constant charging that was keeping it alive! Or maybe there is a wider charging problem.....

My charger describes itself in the documentation as 'Smart', though Smart means many different things to many different people! It says its fine to leave connected to a battery indefinitely. However, I do ride the scoot fairly frequently, so it gets charged up that way, and I connect the charger up when I'm not. I did buy the charger off ebay, and it didn't cost a lot, but it does claim to be made by a British company, though not one I've heard of, though the spec seems good, and its been reliable - though the connector, always a bit fragile looking, seems to have become a bit finicky. The plan is to see if the charger can put in sufficient charge into the battery to get it started so that I can get to the workshop, either for a new battery, or they sell CTEK chargers. I have a CTEK charger for the other Tmax, so it might make sense to have some interchangeabililty! I also have an old Oxford one but can't find it. The Oxford products I buy seem to have the uncanny ability to fall through cracks in the fabric of space and disappear. I'm still looking for my set of 'Hot Hands' wrap-around heated grips. I know I salvaged them from the wreck of the SH300, but just cannot find them!

[abitmad]

"Smart" as applied to battery chargers has only one meaning. That they use a chip as part of the circuitry to monitor the process, thus avoiding overcharging or other problems even though they don't all work in exactly the same way. This is what distinguishes them from the old "trickle" chargers. Just about all bike battery chargers for many years now have been smart. I recently gave away an Optimate 2 that I must have had for about 20 or so years. It was still working fine.

Oxford chargers are shit, in particular they still use old style fragile connectors which are rubbish as they easily bend and break. Optimate used to have the same connectors but presumably because they are so poor, many years ago changed to the reliable SAE type, a common standard also used by US brand Battery Tender. Harley Davidson now fit an SAE type charger lead to their bikes as stock from the factory.

[2wheelover51]

I keep two chargers, an Oxford Maximiser "smart" charger for normal bike/scooter charging and a Gunson 5 amp charger for deep discharges. I'll start with the Gunson and then use the Oxford to top up. You have to monitor the Gunson, watching the charging current drop over time. I use the Gunson mainly for the car batteries or deeply discharged bike batteries.
Another tip when using a normal 5 amp car charger is to connect a side lamp/indicator bulb in series with the battery. As the charging progresses the lamp gets brighter.

[Funkycowie]

Yes, I haven't changed the battery since I bought it, so it is a fair age, though I thought it should last if kept charged properly.

Well I never use a battery tender, so never used one on the TMax for the 3 years or so that I had it, it got ridden most week days.

[MrGrumpy]

Latest news is that the charger says that its charged the battery fully. There is power, but I haven't tried starting it yet. Still rather baffled - is the battery knackered, or is there a drain, and why did the charger complain that there was a short-circuit?

[abitmad]

Smart chargers can appear in a very few cases to have charged a battery fully when in fact it's knackered and cannot hold the charge. In fact they do run a retention test for this but sometimes they can be fooled. However that will happen only on an old battery or, very unlikely, a new or recent one that is faulty. If you have a multimeter you can test this by charging up fully according to the charger, disconnect it and a couple hours later measuring the voltage across the battery terminals. If it's not at least 12.4V the battery is finished.

I may be able to help (no guarantees!) on why your charger showed an ostensible short (presumably you mean a short in the battery cells, not a general short elsewhere) provided it was the CTEK. If so which model and which lights exactly were on/off or flashing?

All this assumes the charger itself is not at fault. It's extremely rare but like anything, they can fail.