All this Optimate stuff! Just sales and marketing if you ask me. A lead acid battery requires a float charge of about 13.8 volts. Whenn you park your bike after running, it shouldn’t need any fancy cycling or monitoring of the battery. Due to sulphating at the base of the plates and possibly and immobilizer (yes they do kill the battery!) the battery will attempt to deteriorate itself after long periods standing
If you get yourself a cheap power supply, the sort they sell in Maplins. Make sure you get one that's cheap and got some space in the plastic case as you need to crowd some electronic in it.
De-solder the wires from the transformer & connect these to a 12volt regulator similar to this….
http://www.maplin.co.uk/module.aspx?...=8067&doy=16m5 with a couple of the essential capacitors.
Wire it up to produce an output of 13.8v by lifting the ground rail from 0 volts on a small trim pot. Slap a load of Araldite or something similar around the wires to seal everything and then connect the output to the wires you originally took off the transformer.
Add a couple of wires from the battery with a fuse and diode in line to prevent shorts and solder them to a sexy little power connector to fit the one on the power supply. Mount this on a small steel plate and a place of you choice with thermal bonding heat shrink sleeving on the back of the wires to keep everything tidy. (I’ve put mine just next to the rev counter).
An hour or so work but what you end up with is a beautifully stabilised and regulated float charger that will not annihilate your battery and hold it at the optimum voltage. I've been doing this for years on many vehicles including my old classic VW Golf Cabriolet I used to have…..Works fine