Charge! Keep your motorbike battery healthy while it's laid up

When a bike’s being used regularly, the battery should stay fit and healthy for several years. But when a bike is laid up – as many are over the winter months, and many more were during 2020’s lockdowns – it can go flat in a matter of weeks.

Machines with alarms or trackers fitted are even more vulnerable, as are those with batteries that are already a few years old. But there’s a simple way to avoid the cost and inconvenience of discovering a dead battery when lockdown finally lifts: fit a trickle charger.

Which motorbike battery charger should I use?

First, check whether your bike has a regular lead-acid battery or a new-fangled lithium-polymer one. Lithium batteries remain rare but have become more common on premium Honda, Ducati and BMW bikes in recent years. There’s also a growing market for replacement lithium batteries. Using a lead-acid charger on a lithium battery has the potential to wreck it – so check if you’re in any doubt.

Assuming it’s a normal lead-acid (or any of the Gel / AGM variants based on the same chemistry) then you’re good to use pretty much any mainstream maintenance charger from the likes of Optimate, Oxford, Ring and so on.

For more, check out our guide to the best motorbike battery chargers.

How do I connect a motorbike battery charger?

Either with crocodile clips or using a lead that stays on the bike. Clips are fine for a short-term connection, but a plug-in lead is more convenient long-term. To fit one (which generally comes in the box with a charger), remove the battery terminal bolts (black/negative first, red/positive second), put the eyes from the charging harness on top of the appropriate terminal, then refit the bolts (this time red/positive first, black/negative last). Thread the end of the lead through your bike to somewhere you can access it easily.

Connect the lead to the battery charger, plug the charger into the wall and switch it on. That’s all there is to it – the charger will fire up and start testing the battery. If it’s all good, it’ll move onto charging and then trickle stages. Unless you see red lights, you can pretty much leave it like this until your next ride.

What if I don’t have power near my bike?

If you’re storing your bike outside, one option is to use a solar-powered charger, such as Oxford’s Solariser (£39.99RRP). These aren’t smart chargers, and their low power output will struggle to recover a discharged battery. But if you’re just keeping a healthy battery topped up, their steady trickle of current during daylight hours should be plenty.

The other option is to remove the battery and bring it inside, where you can charge it with a normal smart charger. This also lets you keep a closer eye on its health, giving the confidence it’ll be ready to fire your bike back into life the second the opportunity arises.