Battery Choice

[sbrumby]

Been haveing some problems with the batteries on the bikes, the batteries i had fitted were 14ah MF the black type that are sealed. The Yam has one of these and the VF has two, One failed after only 3 months & I had this replaced. Now two have failed. They read 13.5v but wouldnt light a candle.
So now i have replaced these with Varta lead acid batteries. The man in the shop said the sealed batteries have fiber between the plates and can have more plates because of this and potentially giving more power but they dont like not being used. the thing i dont like about them, and talking to another motorcyclist that had a similar problem, is the fact they just fail and dont give a warning. Of course if you have an enfield with a kick start its not a problem, but big engine and need to start it on cold mornings, then i would suggest be careful what you choose.

[johnfireball]

Hi,
I had 2 of these sealed batteries fail in my wifes Punto over a 2 year period. Working perfect one minute and totally dead 2 mins later. The new one is also sealed but is sofar 1 year later working well.
John.

[oldbmw]

I think the batteries suddenly failing is because some manufacturers now spot weld the individual cells together as well as the external 12v posts. The welds come apart as a crack which are good enough connection to show 12v on a meter but not good enough to carry any real current. I have had the same thing happen on a tractor battery. was running perfect for about a year, then after using tractor all morning, totally dead after lunch ( during hay making).

[thundercougarfalconbird]

just a few notes about those nice little sealed batteries...
they use a different specific gravity fluid then normal lead acid batteries, they do not like not being used, a battery tender does work well with them, they also require a higher charging voltage 14.8 to 15.2 is very normal for them, rather then the 13.8 to 14.5 for normal lead acid battery, the charging system for a motorcycle or atv with a sealed battery has a higher preset voltage zener diode in the regulator. They are a nice clean choice but they may not be the best choice for the industrial diesel engines with lower voltage charging systems, vibration also shakes them to bits, atv's replace much more often then motorcycles, i have a gas powered bike with factory sealed battery (2003) still works perfectly, but it is on a tender when not in use.
just my 3.5 cents on the topic

[Crazymanneil]

I've bought myself a Hawker Odyssey which makes some pretty impressive claims like working down to -40oC. Not tried it yet to know if it lives up to it though.

Neil