A battery tale

[K1W1]

My XRX was purchased in April 2016 so it is just over 5 years old and has the original battery fitted.
For many reasons including but not exclusively related to Covid lockdowns I have not ridden it this winter.
I last rode it on 2 May. I was started briefly on 3 August but only ran for 2-3 minutes. It has been sitting outdoors under shelter all winter with no battery tender or charging. I went and picked it up yesterday and it started up first kick just as if it had been running every day.
My 2018 Ducati has been even longer between rides but it was started on the same day in August and has been sitting in the same conditions. It also fired first go.
The point of this post is that I see many people on this site asking about battery tenders and the like when they are leaving their bikes for relatively short periods 1,2,3 weeks sort of thing and in these circumstances tenders simply are not required, a modern motorcycle with a battery in good condition will last way more than a couple of weeks without having any charging or starting issues.

[Londonglide]

You do need to factor in ambient Temperature, parasitic draw (alarm, tracker etc), plus some folk still have basic Lead/acid as the most easily available.
For some. its a consumable, buy basic, and replace every few years.
I think its not healthy to leave a battery on permanent trickle, even with modern smart chargers.
If you leave your bike less than a month, and the battery goes flat, you probably need a new battery.

[K1W1]

Originally Posted by Londonglide

If you leave your bike less than a month, and the battery goes flat, you probably need a new battery.

Or something drawing power from the battery that probably should not be.
FWIW the ambient overnight temps where I live will have mostly been between 0 and 5C and daytime under 10C during the majority of the period. Not exactly Northern Europe or USA winter temps but definitely not warm either.

[awjdthumper]

I run a number of cars and from experience I find I can leave them for up to 3 weeks before I need to take them out for a long run to charge the batteries up again. Any longer and a new battery will be required before too long. However, in winter and cold condition, this time period has to be reduced.

I also agree that there seems to be a problem leaving modern motorcycle batteries for long periods connected to an intelligent charger. I am definitely someone who now treats these as consumables and only plug them into the intelligent charger once a week to see whether they last longer than the 2 years the last 2 GEL batteries lasted.

[healdem]

depends entirely by what is an 'intelligent charger'

if the charger has a micro controller it should taper any charge to what it determines is required.
I have used Yeasu taper chargers for numerous years, plugged in for extended periods of time and NEVER had a problem. you can see the charging cycle.. you can see when the charger is dumping as much power as it can and when it is float charging. And that may be part of the problem.. if you have, say a car taper/trickle charger it may be dumping to much current for the very small capcity bike batteries to handle.

It may be that buying a cheapo battery charger from Aldo or similar has issues.. I don't know. but over charging is a known cause of premature battery failure
as is letting a conventional lead acid battery out int he cold without a full charge.
pre the micro electronics revolution the advice was remove the battery if the bike was to be left un used for a while, heck it may still be

but ultimately each tot heir own.
if you have a bad experience with trickle/taper/smart chargers then that's your decision

what I can say is that the batteries on my boat have a significantly longer life when always being charged when the boat is plugged in to shore power AND the batteries are able to keep stuff powered for longer when on long trips. So my choice is to use trickle/taper/smart chargers.
if it extends the life to 7 or more years jobsagoodun. not so long ago people on this forum were asserting that 2 years was about all you should expect from a battery.

[AndrewNZ]

If I go away for eight or nine weeks, at least I used to, I disconnect the battery if it is not connected to anything it cannot drain I have been doing this for many years without any issues and with the battery locked under the seat it cannot be got at easily.
The bikes have always been kept in the garage and even in a bad winter I doubt it'll get below 5c in there.

[K1W1]

Originally Posted by AndrewNZ

I disconnect the battery if it is not connected to anything it cannot drain

Not actually correct. The battery will self discharge over time albeit much slower than if something is drawing power from it. A typical lead acid battery as found in a car or motorcycle will self discharge 4-6% per month but this is dependant on the age of the battery the state of charge at the start and the ambient temp amongst other things.

For those who have Lithium batteries the self discharge is about half that of a lead acid battery.

[awjdthumper]

I only use Optimate intelligent chargers which worked well on my Suzuki GSX1400 original lead acid battery which lasted about 12 years with the charger plugged in all the time the bike was not used. The issue I've had is doing the same with more modern GEL AGM batteries which don't seem to last very long (~2 years). I suspect the Optimates are killing them but I don't know why but, as said, I now use the Optimates just to charge each battery once a week to minimise possible damage. Will need to see how this goes

[AndrewNZ]

Originally Posted by K1W1

Not actually correct. The battery will self discharge over time albeit much slower than if something is drawing power from it. A typical lead acid battery as found in a car or motorcycle will self discharge 4-6% per month but this is dependant on the age of the battery the state of charge at the start and the ambient temp amongst other things.

For those who have Lithium batteries the self discharge is about half that of a lead acid battery.

The drain is still so light its negligible and works for me.