Bike of the Week | The MiRider One GB3 uses an innovative planetary gearbox

To coincide with BikeRadar's inaugural Electric Bike Week, MiRider’s One GB3 is the steed of choice for this edition of Bike of the Week.

Following on from the original One and its electric variant, both of which we rated highly, MiRider has now introduced gears to its folding electric bike, alongside some other updates.

How it’s gone about this is far from conventional, however, so read on as we take a closer look at the build.

A magnesium frame at the centre

At the heart of the MiRider One GB3 electric bike is an ‘aircraft grade’ magnesium alloy frame.

Magnesium alloy typically offers a decrease in weight and an increase in comfort over aluminium, although corrosion can be its downfall.

However, MiRider claims the One GB3 is corrosion-resistant because it subjects the frames to a surface-coating process ahead of paint. The brand says the result is "a durable, hard-wearing finish that protects the frame from all but the worst that the UK roads and trails can throw at it".

It also now uses a one-piece casting manufacturing process over the clamshell halves design previous models employed.

The one-piece casting saves weight, reduces assembly time and eliminates a seam that would otherwise be needed on the frame, which can also present an additional challenge when the frame is being sprayed and looks more aesthetically pleasing.

MiRider says it didn’t want to use derailleurs and a chain for the drivetrain due to the potential for grime build-up through use. The rear derailleur would also likely be in a precarious position, sitting quite close to the ground.

The brand has instead opted to use an Efneo crankset, which houses a unique 3-speed planetary gearbox.

The gearbox is controlled by a GripShift-style shifter on the handlebar. MiRider says the first gear is for climbing or riding without assistance, the second is where you’ll spend most of your time riding and the third is for riding above the 15.5mph cut-out.

In order to use the Efneo system, MiRider has developed its own custom belt drive “to create a quiet and smooth ride”.

New motor and battery

The brand also says it didn’t want to move the electric motor to the front hub, as is found on Brompton’s electric line, for example. It is using an updated 250W motor of its own design, housed in the rear hub. The brand says it performs more efficiently, as well as providing 25 per cent more torque over the original found on the MiRider One.

There’s a new, larger 7Ah battery, too, concealed within the frame at the point where it folds. MiRider suggests a range of up to 45 miles / 72km. The battery unlocks with a key when folded.

MiRider also includes its updated full-colour LCD screen display. This was available as an upgrade to older models, but comes as standard on the GB3.

Folding and specs

The MiRider One GB3 retails for £2,495. The brand doesn't currently sell its bikes internationally, but says it's starting to look at distribution opportunities.

It runs on 16in wheels, shod with Schwalbe Road Cruiser tyres with reflective sidewalls in a 1.75in width.

The bike retains its rear shock for extra damping and there’s a light on the fork crown for added visibility.

The handlebars and frame fold via hinge clips. There is a clip towards the dropout to hold everything together when folded. The handlebars are also height adjustable and the steerer is D-shaped to prevent misalignment.

MiRider’s own MOH pedals fold inwards via a magnetic lock.

MiRider has also specced its own Gemma GA-1000 hydraulic disc brakes, which are an upgrade over the Clarks mechanical disc brakes specced on older models.

There’s also now a Selle Royal saddle – we weren’t fans of the unbranded saddle specced on the non-assisted One, because it was too squishy, so MiRider has clearly taken this feedback on board.

All-in, our test bike weighs 19.013kg including pedals, mudguards and lights.

We’re currently testing the MiRider One GB3 and you can expect a full review soon.