Look Ma, No Derailleur!

GT Bicycles shocked the world in 1997 with an early version of its gearbox bike. At that time, the design wasn’t perfect and, even if it was, it was ahead of its time—consumers weren’t ready to embrace a derailleur-less drivetrain. But after eight years, GT is confident that the time is right and its engineers have finally produced the IT-1, which is designed for freeriders.

According to GT engineers, there are plenty of solid reasons to ditch the derailleur—mainly, the design centralizes a bike’s weight and exposes fewer drivetrain parts to the elements. GT chose to use the internals of a Shimano Nexus 8-speed hub mounted within the frame.

Shimano officials state that the Nexus hub can withstand the loads that GT expects the IT-1 to face, and its efficiency scores in the upper 90-percentile—sapping about the same amount of power as the average chain guide. Although the drag wasn’t noticeable while pedaling, it’s disheartening nonetheless to know that it exists. There is also about a quarter pedal stroke of lag before the gears engaged, which can be troublesome in slow-speed technical situations.

Last, and by no means least, since GT’s gearbox program is still in its early stages and the volume of Nexus components it requires is low, the company lacks the buying power it needs to get Shimano to design custom Nexus gear ratios and a shifter specifically for the IT-1. For now, the bike has a gear range wider than a standard drivetrain and a reverse throw twist shifter, both of which take some saddle time to get used to.

However, shifting is also one of the IT-1’s strengths. The “internal transmission” allowed gear changes anytime, pedaling or not, and it changed gears with a clean, positive engagement during uphill sprints, even with all my weight and power mashing the pedals. Although the bike was a 45-plus pound monster, mashing the pedals hardly affected the rear suspension, making the IT-1 feel downright efficient.

One of the main factors a rider needs to adapt to while riding the IT-1 is the higher, centralized placement of the transmissions in the frame, which changes weight distribution compared to a standard bike. This makes the IT-1 feel top-heavy on swoopy singletrack, but GT engineers still are optimizing the frame geometry to obtain the right balance of agility and predictability on production models. But when the trail turned steep and rocky, the IT-1 felt as stabile as a freight train.

The combination of the adjustable 7 to 9 inches of rear travel, the lack of traditional drivetrain bits on the rear wheel (a.k.a. unsprung weight) and a frame layout that allows for optimal pivot placement equal one thing—a bike that tracks smoother and faster than an average long-travel rig.

The IT-1 performed cruelty free: not a single derailleur was harmed in our testing, and it shows major potential on the performance front. There are still some bugs that GT is addressing for the production models, but if you’re looking for a bike that can handle big drops and big impacts without incident, and you aren’t afraid to be on the edge of the latest technology, check out an IT-1.