Random starting problem

[darrsi]

[quote author=darrsi link=topic=20471.msg237680#msg237680 date=1469078816]
[quote author=Fazerider link=topic=20471.msg237672#msg237672 date=1469052674]
[quote author=darrsi link=topic=20471.msg237643#msg237643 date=1469035624]
We deal with lots of batteries at work so the engineers have a good knowledge of their behaviour, and one of them is totally convinced i have a dud cell.
I have no reason to not believe him.
Should be delivered tomorrow and hopefully he'll be proven right.

A bit late now since you've spent yer money, but a few seconds work with a voltmeter might have been informative.
[/quote]

Did that yesterday.
Battery was on charge all night beforehand.
Went out to check at lunch time, off was 12.4v, engine on bounced around 12.58v, then after about 3mins of engine running i switched it off and it was then 12.6+ volts.
So it is getting a charge to it because it was higher volts at the end of the 3mins, but obviously not holding it too well, or as suggested i've got a dud cell and it's just not behaving normally.
I ride with both headlights on so they will be pulling down a bit of power as well.
If the battery gets there before lunch i'll fit it and test again, apparently new batteries come 75% dry charged and are basically ready to go from new once assembled, although i have access to untold chargers at work so may put it on a very low amp booster charge if it arrives early enough.
[/quote]

I had random starting issues last month - industrial amounts of Halfords contact cleaner in the ignition barrel has sorted the problem and now it starts on the buton.

If I am you I would check that battery myself:

Starting Load Test

• Adjust voltmeter to DC volts (20 volt range).
  
• Place voltmeter leads to the battery terminals. (positive to positive and negative to negative)
  
• Watch the voltmeter as you start your motorcycle.
  
• If the voltage drops below 9.5 volts, the battery has very low capacity and should be replaced.
  

Charging System Test

• Adjust voltmeter to DC volts (20 volt range).
  
• Place voltmeter leads to the battery terminals.  (positive to positive and negative to negative)
  
• Start your motorcycle.
  
• Bring engine RPM's up to approximately 3,000
  
• Compare the voltage reading to the specification in your owner's manual.
  (Note:the voltage reading should be approx. 13.8 - 14.5 volts to properly charge an AGM battery.)
  

From your measuramnets above I see 12ish volts when engine on - that is not enough to charge the battery means your reg/rec is gone IMO.
[/quote]


Measurements were at tickover, a bit of throttle and the figures would've risen.


New battery sorted it anyway, and i've now got in the habit of starting the bike with the lights off to ease the strain.
I should've checked the voltages with the heated grips on as well, they'll probably drain more than the lights i'd imagine.