Electrical Expert Needed! Battery/RegRec/Alarm Questions

Hello,

I have a '99 SV 650s. I bought it about a month ago and it came with a Datatool Veto alarm installed. This being my first bike, I didn't realise how much of a drain the alarms are, I didn't have an Acumen / Optimate plugged in and it had a flat battery when I went to start it a few days ago (one or 2 slow cranks followed by starter relay clicking)

I measured the voltage across the battery - 11.2V. I bump started it, went for a ride for an hour or so and all seemed well. So I thought.

When I came back from the 1 hour ride, the battery voltage was as follows:

bike off: 12.5V
ignition on: 12.2V
voltage during cranking: ~10V
Idle voltage: 12.8V
4-5k rpm voltage: 13.0V

That seemed a little low to me. Out of interest I left the bike a couple days, came back and re-measured the same voltages to see if the alarm had drained much. I found the following:

bike off: 12.2V
ignition on: 12.0V
voltage during cranking: ~10V
Idle voltage: 13.0 - 13.2V
4-5k rpm voltage: 10-11V

Now it seems when I rev the engine, the battery voltage DROPS rather than increases! If I rev to 6k+ it drops to 8V!

I'm not sure how much to trust these readings, as it seems the battery probably isn't fully charged.

I suspect I have a combination of a slightly old and tired battery with a faulty reg/rec. If anyone has any suggestions on my problem please let me know.
I want to charge my battery to full charge and do the same test to get the most accurate results, which brings me on to my next question:

How do you charge a battery with the datatool alarm attached? The alarm handbook says I shouldn't charge the battery with the alarm armed. I'm borrowing a battery charger and I'd like to just put the croc clips onto the battery terminals on the bike, but I don't want to mess the alarm up. Can I just unplug the battery and remove it from the bike, or will this also mess with the alarm?
Ideally I'd like to replace the battery because I don't know the history or health of the current battery.


Any help with these issues is greatly appreciated, bike's meant to be going for an MOT in a few days!

Have a look on Datatool's website for a service mode (if there is one- you may be able to remove the battery after disarming it). It's a very useful website. Read up on de-spiking too (handy to know).

It certainly sounds like something in the charging system is amiss.

[squirrel_hunter]

Originally Posted by drewby89

The alarm handbook says I shouldn't charge the battery with the alarm armed.

Thats news to me. I have a Veto on mine at the moment and I've never been bothered with charging it all connected.

Originally Posted by drewby89

Can I just unplug the battery and remove it from the bike, or will this also mess with the alarm?

If you disconnect the battery the alarm will go off. If you put the alarm in service mode you can remove the battery without it going off, however it will bleep once every 30 seconds.

Get a manual or download a PDF version, with the aid of a meter, you can check the readings of the reg/rec and the stator so it would eliminate the battery or not.

[Sid Squid]

Your voltage readings, (if your certain they're accurate), are insufficient to keep the battery properly charged, the regulator is the prime suspect but it's not the only possible problem. Have a search on here, there is plenty to read, (by myself and many others), on how to correctly diagnose the charging system, and as you have a meter and know how to use it you'll be easily able to pinpoint the problem.

Originally Posted by drewby89

I didn't realise how much of a drain the alarms are

They're not, something is wrong. That, as you've undoubtedly already realised, is that the charging system and possibly the battery aren't doing their jobs properly. If they were they would support your immobiliser for weeks if not months.

Alarms and immobilisers use a truly minuscule current, a charging system which is working anything like correctly will easily be able to support one.

Originally Posted by squirrel_hunter

If you disconnect the battery the alarm will go off. If you put the alarm in service mode you can remove the battery without it going off, however it will bleep once every 30 seconds.

Thanks, this answers one of my questions perfectly.

Appreciate all of the replies so far. I've got to take the bike for an MOT tomorrow, it should be fine to start and get there tomorrow and I'll start fault finding after that.

I'm hoping its a reg/rec problem because I work at Triumph, and I can use one of our 5 wire reg/recs as a replacement with a simple connector transplant. The battery seems fairly strong. Despite only having just over 12V with ignition on, it only drops to 10 - 10.5V under during cranking.

I'll test the stator output and reg/rec voltages over the weekend once the MOT is done.