“It’s a clever and cool project that might be interesting if you’re into bikes, cleverness or coolness.”
Are you like most people that really don’t like all the hassles and problems associated with a front derailleur? Now you have an alternative.
Efneo’s GTRO 3-speed front gearbox is perfect for trekking, hybrid, urban, single speed, city and folding bikes as well as for off road non-competition bikes and e-bikes.
“In an effort to make things quicker and easier, Efneo has developed a 3-speed planetary gearbox to take the place of the front derailleur.”
“If you have ever thought that there must be a better way to change gear than with the traditional front derailleur, then maybe the Efneo 3-speed front gearbox is what you’ve been looking for.”
Advantages for you
- Easy to start from the first gear With Efneo you can reduce to the first gear in a standstill – like in a car – and start easily in 1st gear.
- Immediate gear change Much quicker and easier than with a front derailleur. Change gear when pedalling and in a standstill.
- No chain-skewing No chain-skewing and chain-dropping when paired with a rear derailleur.
- Easy to install The easiest front gearbox to install ever. No frame modifications necessary. No shifter fine-tuning necessary.
- Reduced maintenance No need for tiresome, tricky adjustments.
- Application Efneo’s GTRO Gearbox is dedicated for all non-competition bikes like touring, city, e-bike, folding, recumbent, trike. It has been heavily tested in various conditions (on-road, off-road and labmoratory tests, including winter tests). However, it has not been tested for competition MTB, downhill or dirt applications.
- Gear ratio GTRO’s 1st gear is a neutral gear (1:1). Second and third gears are incremental. GTRO’s standard chainring is 28T.
Gear Ratio Teeth equivalent for 28T 1st 1:1 28T (physical chainring size) 2nd 1:1,43 40T (physical chainring size) 3rd 1:1,79 50T (physical chainring size)
- Interface GTRO Gearbox is compatible with most bicycle frames using standard square tapered 4 flats BB’s with 68 mm or 100 mm wide BB shells, with English thread. BB shell diameter can not exceed 45,6 mm.
- Gear shifting Efneo’s GTRO Gearbox is delivered with a dedicated trigger or grip shifter.
- Rear transmission compatibilty Compatible with any rear transmission (derailleur, geared hub, single speed hub, rear motor) except fixed wheel. For internal geared hub, please check manufacturer’s specs for the smallest front chainring allowed.
- Learn more in full technical specification.
Full technical card
How to install
Testimonials and reviews
So, I’ve put about 500 miles on the gearbox and i can say that it was totally worth the wait. I am including some pictures of my rig. Right now I am riding a Surly Big Dummy as a daily commuter. I live in the NC foothills and need to transport a fair amount of gear on a daily basis. For the drivetrain, I wanted something that was low maintenance…no derailleurs. The rear hub is a Nuvinci N360 which pairs well with the Efneo gearbox. With 3 gears up front and a CVT in the rear I have an almost infinite range of gear ratios.
The Efneo gearbox was easy to install, about 10 to 15 minutes. Shifting is super smooth and my top speed has increased by about 25%. One of my favorite things about this crank is that the physical 28T sprocket provides a huge amount of chain wrap. This means I am driving more power to the pedal even when I drop to the 40T and 50T settings. This will definitely be a must have for all future builds. let me know if you would like any other photos or testimonials.