Motorcycle Battery Charging?

The maximum charge rate for a battery is ~10% of its Amp-hour rating. 0.5A is, in real terms, right on the upper limit for the battery. Indeed, a smaller motorcycle battery will radiate heat more quickly than a large battery, so they can take a tiny bit more charging abuse.

Batteries are charged at the current set by the charger - your 1.25A charger will charge AT 1.25A and will therefore deliver a little bit too much current. The risk is overheating (risk of pressure-build from excess hydrogen in the battery), risk of evaporation of electrolyte, risk of overheating and deforming of the plates, ultimately a risk of internally shorting the battery if the plates manage to buckle enough to make contact in one of the cells. 1.25A, however, isn't enough to do all this to a battery - but it is enough to put the battery's service life into question and certainly enough to void the warranty.

My best advice? Don't use a battery charger, don't use a trickle charge manager. I firmly believe they shorten a battery's life. Obviously the vendors of such items will angrily disagree with me but they would. I own and run two bikes. I DO NOT own a battery charger. If you're taking your bike down for winter (I don't by the way), then remove the battery as fully charged by a good run on the bike and keep it nice and warm and dry in a cupboard in your house. A decent battery will still be good in March. If it isn't, then it wasn't so decent.If you do buy a charger, then only charge the battery every two months for a night, don't leave it connected up.

Hello

If it states Max 0.5 Amp and you charge at 1.25 Amp that would be like putting 2.25 X the recommended pressure in your tyres. Get one that trickles at 0.5 Amp.

Andy C