All starter; sprag and flywheel re-assembled properly ready for alternator cover to go back on (alternator not connected though).............just thought I would connect battery to see if it would turn over.................turns over without the plugs in, but not when plugs in.............just comes to a standstill, suggesting low charge battery. All battery/starter/relay connections good. Battery 'fully charged' although I note that the needle on the charger doesn't drop below 1 Amp after a day on charge (it normally dropped to 0.5 Amp or just below)....... But, doing a voltage test on the battery it reads 12.36, which should be enough........or is this battery knackered? Any ideas? AL
If it's just come off the charger it should read about 13.2v, dropping to about 12.7v after a few hours. At 12.36v off the charger it's knackered.
When you say a battery test, what is the load for a terminal potential of 12.36 Volts? Or is this just an Open circuit measurement? When spinning the engine over without the plugs what does the voltage drop to? Assuming Lead acid technology.
Just testing the battery on the bench to see what the voltage reading is........Lead Acid type at least six maybe seven years old......could be more.........it's a cheap Yuasa lookalike. ......I'm assuming the voltage drop with the plugs in is bad, but as I don't have the alternator cover on, I don't want to keep turning the engine over, 'cos there's no oil in it...........only done it for about two revolutions. Derek....I expected it to be at least 13 Volts as you say.........It's been off the charger a day.....and it has previously been losing power slowly over a week or so (nothing to drain it) but it could normally just get the engine spinning and fired up. I'm going to try jump leads straight to the starter tomorrow, although I'm happy with all the connections in the circuit. Thanks both..... AL
Al, put a multimeter on the battery while pressing the starter, if it drops bellow I think 9.5 the battery is knackered, my son's battery showed full charge and when tested as I suggest it dropped to 3.5 v. Steve
the best test of battery health is to measure voltage drop while cranking starter motor. If it drops below 9.5V as @Birdie suggested, the battery is either empty or bad. I would be not surprised that 7 year old battery has died.
I agree. My 6 or 7 year old Yuasa lookalike ("Wind" brand) died last year - it could no longer turn over the 900SS engine even after prolonged charging; sorry, I can't remember how voltage behaved though. I replaced it with a genuine Yuasa as there did not seem to be much of a saving by going for something else.
Thanks all....... Will test the battery voltage again under load.... As a matter of interest, does anyone use Loctite on the two nuts of the pick-up adjustment plate? AL
Get yourself a Motobatt. They are lighter, hold more charge for longer and have better amps to turn the bike over than the likes of an overpriced Yuasa. Not sure where you want to use loctite, but if its around battery area, no need.
The battery which appears to be playing up is a Rob Hunter one........It was fitted by one of the previous owners over six years ago for certain. I was querying whether anyone uses Loctite on the arrowed nuts in the pic below.
I suppose they might have Loctite used at the factory on the basis that they should never need adjustment (until something else breaks and access is needed!), but I can't see that it's necessary as no torque is applied to them when the engine is running, and I would hope vibration is not going to make them loose.
That's my thought too.....although I suppose vibration could possibly shake them loose.....Now I have the plate back in place and the nuts tightened, I'm thinking of either unscrewing each nut in turn, Loctiting and tightening while holding the pick up/plate against the feeler gauge at the same time.............Or just blobbing some cellulose paint on the end of the thread and nuts, without removing the nuts (I'm never convinced that a secure method, though).
I never used to use Loctite on the little screws that held the plate with the contact points on it in place, in the bad old days of bikes with non-electronic ignition. I quite like the paint blob method myself, but not as a way to lock things - just a way to see if they have moved later on (especially for cases like a big nut holding a front sprocket on!).
Sounds knackered. Or, no good for Ducatis. I've had batteries not start my 996 but fine on my gsxr 1100 and my TL. If you've got other stuff it might be worth keeping as a spare.
Having got the bike more or less back together, I don't intend filling the bike up with clean oil and starting it up only to find the damn nuts come loose..... I ran jump leads direct from the battery on the floor, to the starter and the engine case (so I could touch the negative with the lead)........watched the multimeter drop from 12.6V to 3.6V over three touches....I guess it is sh*gged. Probably finished itself off as it slowly screwed the sprag spring up. Still, I can always use it for reading under the bedclothes at night.......
With a dud battery, you could end up potentially wearing out another component of the bike, starter motor for example. ( a mates hayabusa will burnt out the starter clutch from a weak battery - as an example. Costly to fix ) Be done with it and buy a new Motobatt.
al if I remember correctly 12.7 volts or above is a fully charged battery 12.3 is about 30-40% down on charge seems like a dud cell
One of my batteries started showing a yellow light on the optimate the other day. I unplugged it and measured the voltage, I got 12.56v. I was going to ask the question as to whether it was no good on here, but it looks like this has been answered. New battery me thinks. It has always been fine until it was left unplugged for a couple of months while I worked on my garage, It was flat as a pancake after this and I think this is the cause of death ead:
I was riding my KTM, which is more vibey than the Ducati, on Sunday when all the warning lights came on and the rev needle started sweeping round the dial and back again. I pulled over and lifted the seat to check for anything obvious like a blown fuse or a loose connection and found the bolt on the positive battery terminal had gone and the lead was off. I reconnected it and all warning lights went out and everything functioned normally but I use locktight on the terminal bolts now. When I got my Sf back from Louigi-Moto after tuning work it had higher compression and more valve overlap. Rich said don't use an optimiser because he believes it weakens the battery and better still fit a lithium battery. I think I will do that. The regular battery doesn't turn it over that strongly even when in good condition. I don't find the Ducati too battery hungry. I can leave it for a month and it will start no problem. The KTM left standing flattens its battery in a fortnight.
