Given that the ZX10 is so old, there is no drain on the battery when off, would you leave it on the bike when not in use, with conditioner on (permenently, or weekly/monthly session?)?
We leave our's connected permanently, the conditioner/charger only outputs 800mA maximum which is spot on for the batteries we have (12Ah & 14Ah) and it does know when to charge and when not to so the battery doesn't get cooked.
Any advice on where to buy batteries from?
Unfortunately not, I got the last one from a small (backstreet) independant just around the corner from where we live and it was a Yuasa that was delivered to them (dry).
It is standard lead/acid and cost £25 about 5 months ago including the acid fill.
Given my current battery gases a fair bit, would gel or fully sealed batts be better?
Like you I suspect your charger may have been putting out a bit too much charge current (hence the gassing). An ideal bench charge rate for a battery is one tenth it's Ah rating.
I don't think a gel battery would last very long to be honest, gel batteries require different charging voltages (slightly lower than lead/acid) and the charge rate has to be more tightly controlled (which your regulator won't be able to do).
Failure to observe the charging rules for gel batteries leads to their early demise quite quickly.
As far as a sealed LA battery goes, the only advantage I see to them is that you can't get burnt if you inadvertently knock the battery over. I personally prefer the ability to top the electrolyte up if it's getting low.
One of these puppies, Martian?
http://www.amazon.co.uk/Ctek-CTE-XS08-6-Stage-Smart-Charger/dp/B004RADNCQ
That's the very same
