Anyway... voltmeter shows 13.6 to 14 volts when running. 13.0 idle. 12.4 engine off.
Originally Posted by pibyk
Well, I am not an expert at all but you may consider the following:
a) it appears that this bike does not like low quality fuels or fuels which are contaminated (allegedly for the sake of environmental friendliness) with ethanol or so called bio-esters so I would try to shop around for a better fuel, especially that from what I know, ethanol is a very popular fuel additive in your parts of the world.
b) booster plug in principle cheats the system so it does "think" that it is colder than it is which in turn results in (slightly) higher volume of fuel injected - in your case it looks like the bike is more friendly when warm, so you may try disconnecting booster plug and check the result. In my case was the opposite - in cold weather the bike was more user friendly.
If you are sure that your battery is in perfect working order, then combination of booster plug and improper fuel may be the reason behind your problem. I have never had this sort of issue - maybe once or twice it died just after firing but it was in really cold weather (below 0 Celsius). I have booster plug and Leo Vince exhaust installed. Stock battery died very fast so I have it replaced with Yuasa.
best regards, Piotr