Gboost

The offer

What Gboost actually is

Gboost is one configuration from Gboost, made in Europe, filed here as a friction drive. The family is Drive, generation Catalogue. Compact European drive listed at 250 W with packs from about 251 to 441 Wh.

In the box, as this record has it: Drive unit, Pack. Still required before the bike moves under its own assist: Mount clearance. A cheaper advert for the same family name is not this list. If the battery, the charger or the throttle differs, it is a different configuration and it gets a different page.

250 W. Pack sizes in the press table run 251–441 Wh.

The price on the card is the maker’s published figure in EUR, or Maker list when no figure was published. Allowances for a missing pack, a charger and workshop time sit in the complete-cost band. They are not a second product and they are not a promise that a random pack will talk to this controller.

The bicycle

The frame this motor is asking for

Gboost lists Gboost against Road, Hybrid, Folding bicycles, for Commuting, Leisure. Wheel sizes on the card: 700c, 26, 27.5. The mechanical interface is Frame mount. Brakes are disc.

This architecture does not replace the axle or the bottom bracket. The question is whether the mount — roller, rotor, seat stay or hitch — has a flat, strong place to live, and whether the tyre, the disc or the seat post is the one the maker designed for.

Pedals stay. This configuration is a bicycle with assistance, not a motorcycle conversion. Sensor on the card: torque. Cut-off on the card: 15.5 mph. Throttle: not fitted.

The numbers

250 W is not the whole story

Continuous rated power for Gboost is 250 W. Claimed peak is not stated separately from the continuous rating. Torque is not published as a crank or hub figure. Manufacturer stated. Motor mass is not published. System mass, once the named parts are on the bike, is Drive unit, Pack.

Peak is a short claim. Street rules, including the Great Britain check on this site, use continuous rated power and the speed at which assistance stops. A controller that can be unlocked does not change the record of the motor as sold. Gboost is filed in the 25 km/h class: 250 W pedelec class used across the EU, Great Britain and Australia.

In this class the useful comparison is torque and mass, not a bigger watt sticker. A 250 W torque-sensing mid-drive and a 250 W cadence hub do not feel alike, and neither of them becomes legal somewhere else just because the sticker matches.

Pack and charger

The pack is part of the kit

Gboost pack is 251 Wh at 36 V. Lithium-ion The charger is Included charger.

Nominal watt-hours are voltage times amp-hours when both are known. That is stored energy on the label, not usable energy, and not a mileage promise. Cold, load, hills and how full you dare to run the pack all move the distance. Any range sketch on this page shows the watt-hours per kilometre it assumed.

Charge this pack with the charger named for it. The same plug on a higher-voltage brick is the wrong part. A swollen, hot, hissing or sharp-smelling pack is a stop: do not open it and do not keep charging it.

Friction drive

How Gboost uses this layout

Friction drive. Gboost presses a roller into the tyre instead of rebuilding the wheel or the bottom bracket. Lift the roller off and the bicycle is itself again. That is the appeal, and the limit.

Grip is a tyre question. A slick in the wet, a soft sidewall, or a roller that meets the tyre at an angle will slip or chew the tread. Pressure, spring range and a square contact patch are the install, not an accessory.

Noise and a small flat spot on the tyre are normal topics for this architecture. They are not a reason to pretend it is a hub motor.

The workshop

Specialist, even if a shop is doing it

Gboost is marked specialist. An online fit is a brief. The stand still has to see the frame. Cargo, long chainstays, unusual dropouts and this architecture are why the automated check stops.

Warranty as published: Maker warranty. Term is on the invoice.. Labour in the cost band is separate from the offer. A brake service the bike already needed, a new chain, or a hanger alignment is not folded into Gboost’s price to make the total look neat.

The sensible order is measure, then mount, then connect, then the first assisted roll in the stand. Connectors are keyed for a reason. The torque arm, the axle nuts and the connector boots are one inspection at the end, not three trips.

After it is on

The first month, and the parts that wear

Look at the tyre where the roller runs. A flat patch, a glaze, or a chunking sidewall means the pressure or the alignment is off. Carry the right tube. The roller is not a licence to ignore a soft tyre.

Keep Included charger with Gboost pack. Store the pack cool, part-charged if it will sit, and not in a hallway that is your only exit. Gboost’s display, if one is included, is paired to this controller generation. A screen from the next family is not a spare.

My Garage on this device can hold the configuration, who fitted it, and what was still open. That note is for you and for the next workshop. It is not a certificate. If a later notice lands on this configuration, the record is where it should show.

Read next to it

• RubbeeRubbee · Friction drive · 25 km/h
• HillTopperHillTopper · Friction drive · 20 mph

From the library

• What a conversion kit actually includesA motor wheel and a complete system are not the same product. The page should say which one you are looking at.
• Watts, torque, and the sticker that does not mean rangeContinuous watts, peak watts and newton-metres describe different moments. Mixing them is how a listing looks twice as strong as the motor you will live with.
• Speed classes, from 25 km/h to off-roadThe class is a property of the kit as sold. The road you may use it on is a property of the country, and sometimes of the state or the canton.
• Friction drives, dry roads and wet onesA roller against the tyre is the most reversible conversion, and the one most sensitive to the tyre you already own.
• Converting a folding bikeSmall wheels, hinges and a short front end. The kit has to fold with the bike, or you will fold it once.