New 959 Owner (2 Days!) - Bike Won't Turn Over / Start

Batteries are strange things and have an unfathomable relationship with bikes and cars. They live in a happy marriage for years, then, gradually or suddenly they start to have disagreements which flare up at unpredictable times in unpredictable ways. Counseling does little good. A clean divorce is the only thing that works and a new partner.

 

So, can we hear it start yet?!? Hope you’ve managed to get it sorted mate

 

I’ve got a spiel that I often end up posting on FB re batteries...but it is useful here I think.
Ps..hope yours is all sorted now.


Batteries.
There has been a fair amount of discussion on various pages about batteries and them failing. And blaming this bike or that bike or whatever.

So anyways here's a bit of science. I'll be using the battery from my MV F3 as an example. This is an 8.6Ah battery. Your battery is probably bigger (physically) than this.
What does this mean? Well, it means it can deliver power equivilent to 8.6Amps for 1 hour, or any combination thereof. 1A for 8.6hrs for example. This is a huge simplification as the temperature of the battery (there is less available charge when cold), and the actual current draw (it becomes less efficient the higher the current draw) all affect things...but it'll do as a start.

Now - unless there is a fault on your charging system (see the end for how to diagnose) if the battery fails it *is not* the fault of your bike. No matter what the make of the bike.

If an automotive battery drops below 10V it is probably toast. How could this happen? Well, lets say you have an alarm - say the alarm that was on my old R1 - a Ross Meta 351A.
This draws 10mA when armed.
So, this tells me that in 860hrs the battery will be completely drained if there is no charging going on. However, the battery will be completely killed long before that - if a battery gives up around 3/4 its charge without recharging...it'll probably be good for nothing soon after.

So...in 645hrs of not riding the battery is knackered. Just over 3 weeks. Less if the weather is cold. Like winter. When we don't ride.

You might be able to recharge the battery and "recover" it - however it won't hold as much charge as it used to.

On older bikes this wasn't such a massive problem - as you switched them off, and then they were off - any alarms aside. But modern bikes have ECUs that are "smart". They hold custom maps and a clock and trip counters and all that - that is stored in RAM and needs power even when you switch the bike off.

So, put an alarm on a modern bike - and hey, lets have a tracker too and you're probably looking at 45mA drain...on my F3 that means just under 8 days before the battery needs replacing.
This is why my MV came with a battery trickle charger.

But but, you shout, I keep my bike on a trickle charger and the battery still died after 18mnths....WTAF?!

Well, consider this - at the dealer where you bought your bike. Were all the bikes on trickle chargers? Didn't think so. A good dealer will uncrate a bike, fully charge the battery before connecting it, do the PDI and then disconnect the battery - and fully charging the battery before storing it.
And only reconnect the battery when the bike is about to be driven away sold. And when they get a second hand bike in...they'll do the same. If your bike was sitting on the shop floor for a couple of weeks with the battery connected....yeah...you will need a new battery.

How to test your battery (see attached image).

And to test your charging system - start the bike and rev the engine to about double idle speed (I was going to say 5000RPM, but that'd screw with big v twins etc)..the voltage across the terminals should read above 14V and below 15.5V

If it is below 14V it might be that your battery is quite flat and is drawing all the charge it can take - but if the battery is fully charged then it shows that either your generator is knackered or (like in my 20yr old RVF) the original wiring loom is rubbish and taking too much power or your reg/rec is borked and giving nothing out. Get someone to look it at and check it out, your battery will keep going flat if you don't.
If you're reading above 15.5V chances are your reg/rec is on the way out - get this fixed ASAP as it will boil your battery (cheap to replace)and possibly burn out your ECU (not cheap to replace).

Oh, yeah. Even if all the above is perfect, absolutely perfect - batteries die with age anyways after around 3 or 4 years. They are a consumable item.

Hope this helps.

 

I don’t follow too many threads but you’ve got me hooked! This is up there with waiting for the next James Bond film. You’re killing me with your Hitchcock style suspense.
Until Saturday then.....

 

I note that this is rated at 36Watt Hours - which equates to around 3 Amp hours....as opposed to 8.6Amp hours in my old MV's (very tiny!) battery. So whilst LiIon batteries won't self discharge and you can run them flatter than a normal battery, and they are *far* lighter - they are actually lower overall capacity. Keep it on a charger when not in use if you have an alarm or a tracker.

 

Sounds about right. So possibly half that on a lower capacity battery.

 

All good in the world again!

 

I need a video of it starting otherwise I don’t believe you!

 

My 899 exhibits exactly the same behaviour today...click click click.

Thanks to @manicguitarist I think I now know what to do to get her fired up and stay that way.

 

One of the reasons I've been half heartedly thinking if selling my 1098. It'd wake the dead. Was epic at first, but it's getting slightly embarrassing tbh.