NEW.GTRO 3:SPEED INTERNAL GEARBOX CHAIN.SET

An updated, compact front-mounted 3-speed gearbox, made in the UK, that replaces a traditional triple chainring with a cleaner, tougher drivetrain. Because the gearing sits at the crank, the chainline stays straight, so there's no front derailleur, no chain rub or chain drop, and much less maintenance.

Gearbox

• The ratios are 1:1, 1:1.43 and 1:1.79.
• First gear is direct drive; second and third are step-ups.
• It shifts cleanly into first from a standstill or under load.
• Shifts are faster and simpler than with a front derailleur.
• There's no chain rub or chain drop, even with a rear derailleur.
• It's low maintenance and needs no lubrication.
• It has been tested on-road, off-road, in the lab and in winter.
• It comes in gloss black as standard.

Fit and compatibility

• It suits trekking, hybrid, urban, single-speed, city and folding bikes, plus light off-road use, e-bikes, trikes and light touring builds.
• It's not for race MTB, downhill or dirt jump.
• It has a 5-bolt spider for 130 BCD chainrings.
• It fits most frames with an English BSA bottom bracket, and needs no frame modifications.
• The bottom bracket shell's outer diameter must not exceed 45.6mm.
• It also fits most popular folding bikes.
• Use it with a trigger or twist shifter.
• It works with a normal rear drivetrain, including most rear systems (derailleur, gear hub, single-speed hub or rear motor), but not fixed-gear wheels.
• With an internal gear hub, check the hub maker's smallest permitted front chainring.
• It's the easiest front gearbox to fit, no harder than a normal chainset.

Ordering

• The lead time is 1–2 weeks from purchase.
• Get in touch for details or special requirements.
• Sales outside the UK may incur local duties. A shipping option with EU duties included is available at checkout for higher-value items.