Review: Katbo 2-amp 6-volt battery charger

One of the fun parts about running a motorcycle that’s been restored or rebuilt by someone else is the little things you discover after a few months of ownership.

In the case of my 1963 Velocette Venom, it was a surprise to me when removing the battery and finding it had a fake exterior, which did look original and period, with two Lucas sealed lead acid rechargeable batteries inside, wired in parallel. Wiring in parallel retains the original voltage, in this case 6 volts, while doubling the amp hour capacity.

Inside the Velo's period looking black battery box are two Lucas sealed batteries
Inside the Velo’s period looking black battery box are two Lucas sealed batteries

The reason for investigating the battery wasn’t just curiosity. It was flat and although the Velo has magneto ignition and therefore doesn’t need the battery for starting, I was surprised since everything about the motorcycle is immaculate.

So why was the battery flat? Was it a duff battery or was the bike not charging?

First thing though, I wanted to charge the battery and my existing battery charger was 12 volts only. I fully intend to change the Velo over to 12 volts over the coming winter, along with a few other jobs, so didn’t want to spend a fortune on a 6v charger.

Quick browse on Amazon and up popped this Chinese made (of course) Katbo 2-amp charger for £23.99, with next day delivery. The ratings showed 4.3 stars out of 5. Amazon star ratings are not always reliable but 4.3 was a lot better than just one star, and at that price not the end of the world.

Packed full of tech

The Katbo battery charger is packed with a stack of technology if you’re interested in this stuff, but I just wanted it to work. Turns out some of its tech is actually useful.

When disconnecting the batteries from the bike I noticed a red earth wire and black live wire. Convention says red is positive, black negative so when connecting the battery charger that’s what I used. Katbo say no, wrong way around. Fortunately, it did that before any damage was done.

Anyway, connected the correct way around, the Katbo’s LED screen display is clear and automatically scrolls through to show what’s going on: battery voltage, charging voltage, % of charge, real-time current display.

The batteries were fully charged quickly and the Katbo can also be used as a trickle charger, useful if you don’t use the bike very often.

Back on the bike, everything worked as it should… except the Velo’s ammeter was showing full discharge when the headlight was switched on and the engine running. It’s not charging.

Off with the seat and tank so I can follow the wiring all the way and see if a connection is loose anywhere. Quick check of the voltage regulator under the seat and another surprise. Under what looks like a period voltage regulator cover is another modern touch – a solid-state DVR2 regulator from Dynamo Regulators Ltd. Nothing to check there then. It either works or it doesn’t. The dynamo is a Miller reconditioned just a short while ago so that should be alright.

So far, no joy. The Velo runs fine because of the magneto ignition. The lighting all works fine so long as I keep the battery charged. But the charging system isn’t doing its job. D’you know what… since I’m going ahead with the 12-volt conversion over winter – to get better lighting – I’ll put up with it for now.

Katbo battery charger on Amazon