Trek Rail 9.9 CXR Gen 4

The "Rail 9.9 CXR Gen 4" model from Trek, released in 2024, is a state-of-the-art e-mountain bike designed for discerning riders. Priced at EUR 12,999, it belongs to the premium class and offers a wide range of advanced technical features and high-quality components.

The bike’s main frame is made from OCLV Mountain Carbon, ensuring high stability and low weight. The frame features a 1.8" lower top tube and is compatible with the Bosch System Controller. It also features a Removable Integrated Battery (RIB), Knock Block 2.0, guided internal cable routing, a seat tube diameter of 34.9 mm, a magnesium shift lever and Motor Armor.

The bike’s maximum permissible weight is 136 kg, whilst the bike itself weighs 22 kg. The front and rear brakes are Shimano XTR M9120 hydraulic 4-piston disc brakes with a Shimano RT86 6-hole disc mount and 203 mm brake discs.

The drivetrain consists of a Shimano XTR M9100 12-speed shifter and a Shimano Dura-Ace/XTR M9100 drivetrain. The fork is a RockShox ZEB Ultimate with AirWiz, DebonAir spring and Charger 3 RC2 damper. It is optimised for e-MTBs and offers 160 mm of travel.

The bike is fitted with VP-536 nylon platform pedals and an ethirteen espec Race Carbon crankset with a crank arm length of 165 mm. The cassette is a Shimano XTR M9101 with 10–51 teeth and 12-speed.

The handlebars are Bontrager Line Pro made from OCLV carbon, with a width of 780 mm and a rise of 27.5 mm. The grips are Bontrager XR Trail Elite with nylon clamps. The stem is also a Bontrager Line Pro, 45 mm long, featuring Knock Block and Blendr compatibility.

The tyres are Bontrager SE5 Team Issue Tubeless Ready with Core Strength sidewall protection and an aramid bead core, in size 29 x 2.50. The wheelset consists of Bontrager Line Pro 30 OCLV Mountain Carbon rims, which are tubeless-ready and feature a 6-hole disc mount.

The saddle is a Bontrager Arvada with austenitic struts and a width of 138 mm. The seatpost is a Bontrager Line Elite Dropper with a 170 mm drop and internal cable routing.

The bike’s motor is a Bosch Performance Line CX Race Edition Smart System with a magnesium motor housing and assistance up to a maximum of 32 km/h (limited to 25 km/h in Europe). The battery is a Bosch PowerTube with a capacity of 750 Wh, also part of the Smart System. The display is the Bosch System Controller BRC3100.

The bike’s geometry comprises a reach of 49 mm, a stack of 64 mm, a seat tube length of 45 mm, a top tube length of 64 mm, a head tube angle of 65 degrees, a seat tube angle of 71 degrees, a head tube length of 12 mm, a chainstay length of 45 mm, a standover height of 77 mm and a wheelbase of 128 mm.

The Trek Rail 9.9 CXR Gen 4 thus offers an impressive combination of advanced technology, high-quality components and well-thought-out design, making it an excellent choice for discerning mountain bikers.