Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 998 / 996 / 916 / 748 > A battery problem?

[yellow916]

My 916 has been getting difficult to start when warm (i.e. after being parked up for a while after a run) - very sluggish turnover. The battery looks like the original, so I thought I'd replace it.

I got a new one, put it in and connected the Optimate (III) as instructed. The red "Desulphate" light came on, followed eventually by the "Weak" light. I took the bike for a run last weekend, difficult to start as ever when warm.

This didn't seem right, so I took the battery back and got a replacement. Installed it as before; this time the "Charge" light came on, then the "Weak" light again...

It seems unlikely (or very unlucky) to get two duff batteries. Do Optimates go wrong? I did put the old battery in while I exchanged the new one - got the "Green" light on the charger then.

TIA

Andrew

[Fordie]

Must admit my Optimate now about 2 years old and used all the time has a tendency to some times show a red light for no reason . I normally just turn it of, disconect it reconnect it and it goes back to the normal charging state ? Bike starts ever time . 4D

[DAVE HARRIS]

I had this problem with annettes sps, it would start fine when cold but was sluggish when warm. After changing batteries, checking for bad connections etc it turned out the flywheel nut was loose! if the it sounds like the clutch is knocking badly take off the lefthand side fairing and look through the timing winow on the flywheel case, if the nut is loose you should be able to see the flywheel wobbling at tickover.

It is possible that the starter is worn but our old 916 has done around 30,000 miles and still starts ok!!

dave

[yellow916]

Dave/Weeksy

Thanks for the replies. I hope it isn't that nut - Baines had the engine in bits about 2k miles ago to rebuild the gearbox :-( Does sound like a charging problem though. I'll search for reg/rec as suggested.

Andrew

[748mart]

I would remove battery from bike & charge with optimate on bench for 24hrs. If you have a meter measure voltage, if voltage on charge is high above 15V I would suspect battery, if below 12V suspect optimate. when charged should be about 13V & on charge about 14.5V.

[phil_h]

1. Personally I'm not using my optimate any more after too many problems with it not charging batteries on my various toys - which my accumate almost always charges with no problems.
Advice is not to trust it as much as the advertising says !
(I've also just bought a swedish job to try as an alternative)

2. If you ever get poor charging performance with the bike electrics still connected - its probably the regulator ! (I've just had that problem on my tt2 for instance). More expensively, it could be an alarm problem if you have one fitted.have one.
SO - just disconnect the wiring and try charging again.
(What - you've never heard of problems with duc regulators :-) )

[moto748]

Had a similar thing recently. Battery would suddenly appear flat, despite bike being used most days. First suspects were battery and reg/rect. Battery was charged on Optimate and seemed fine. Left on draining board, disconnected from bike, and voltage drop over a couple of days was negiligible. Reg/rect charging voltage checked, and fine at 14-14.2V. Reg/rect charging voltage checked when bike was hot (I've had *that* one before!). Likewise fine. Continued to find severe voltage drop when battery connected to bike.

Disabled/disconnected alarm unit

No more probs! Getting a replacement alarm unit fitted under warranty tomorrow.



Moral; it ain't always the reg/rect. Even on a Ducati. (Although I believe the later 3-phase ones like mine are better. But not perfect.)

[Edited on 15-10-2004 by moto748]

[Derek]

Andy,

I don't know about the Optimate, I've never had one, but regarding the charging on the bike, connect a voltmeter across the battery on the bike and set it to DC Volts. Just off charge it should show just over 13V this will drop to the high 12s after an hour or two. On switching on the ignition it will drop but should be by no more than a half a volt or so, any more and your battery is dodgy. When the engine is started you should see about 13V - 13.5 V at tickover rising to about 14V - 14.5V at 3000rpm + . If you don't get these figures the alternator or regulator is faulty. Unplug the 2 yellow leads from the alternator and connect the voltmeter across them set for AC Volts. You should read about 15V/1000 rpm. ie about 45V at 3,000rpm and 75V at 5,000rpm. If that is OK then the fault most likely lies with the regulator (and generally does).
I think it is unlikely that you've got two duff new batteries but sluggish starting implies that the battery voltage is down. However it's also worth checking the connections to the starter, particularly where the cable from the solenoid connects to the starter. It can collect water and muck under the rubber boot which causes corrosion at the terminal which reduces the current available for starting.
Hope this helps.

[haggizbasher]

Andrew

I've used the same optimate for the last three years, 2 years on a jap bike, 1 year on the Duke. I had to replace the battery on the Duke, although I couldn't understand why as it was only 1 year old and was always connected to the optimate....! While I was in the garage getting a new battery, I was telling Andy (yellowisfriedegg) about the problem....he suggested maybe I had switched on the Optimate BEFORE I connected it to the bike as this could damage the battery.....I wasn't sure if I had or not....After fitting the new battery I always make sure it's connected first, then switch on the optimate.........Since then, I've had no problems...hope this help....

Stuart

[yellow916]

All

Thanks for the various suggestions. I did some measuring over the weekend...

Charged the new battery for 24 h in the bike - 12.47V

Got green light on Optimate for a while, then only the red "Desulphate" light. Changed to using the croc clips rather than the wired in connection, correct lights (yellow then green) every time, so the wired in connector is suspect.

In the process of doing all this, the alarm (Datatool Veto Plus) decided to play up - no beeps, no lights, bike immobilised. I followed the drain-down procedure from Datatool, now I get the red light on the dash on all the time, it beeps as if it's in Service mode, but the bike starts (and the alarm beeps while it's running).

Checked voltage on bike with engine running - 14.2 V at tickover, about 14.6 V at 3k rpm, which sounds about right.

The other thing I did was take all the wires off both battery connections and cleaned them - they were filthy!

I've now left the bike on the battery but not on the Optimate. Presumably if there's a short somewhere it'll discharge over two or three days?

I suppose the r/r could still be suspect - time to invest in one of those solid state voltmeters Shazaam recommended maybe?

Any further thoughts appreciated.

Andrew