Since your mountain bike rides will get longer and longer, it is important to have a suitable seat. So our teams designed the exclusive ROCKRIDER Ergofit Evo saddle. It fits all hip sizes and has a curved shape that is particularly good for sport trail rides. The 31.6 mm aluminium seat tube ensures compatibility with most dropper and suspension seat posts on the market.

The E-ST520 electric bike is equipped with a single chainring and ChainFlow 3D anti-slip technology to prevent the chain from derailing. A single shifter on the right handlebar makes it easy to shift between the 9 speeds. In detail:, -Chainflow & anti-drop single chainring with 34 teeth, -MICROSHIFT ADVENT 9-speed rear derailleur with long cage, -MICROSHIFT ADVENT right shifter, -MICROSHIFT H092 9-speed cassette (11-42 teeth), -KMC E9 Sport electric bike-specific chain

No matter the conditions you ride in (dry, muddy, wet), the Tektro TKD88 hydraulic disc brakes at the front and rear provide powerful, progressive braking. Oversized 180mm diameter discs provide even more power.

These wheels were specially designed for this mountain bike:, - 23 mm rims (width between brackets), 28 spokes at the front and 32 spokes at the rear, for greater durability and good grip with wide tyres (up to 2.5"). - BOOST thru rear axle (12x148) for greater durability, - Aluminium hubs with sealed bearings, - TUBELESS READY rims: you will need tubeless tyres, Presta valves, and puncture sealant.

So you feel safe on any terrain, and for traction suited to your motor, the E-ST520 electric MTB is equipped with Hutchinson Cougar 27.5" tyres with a 2.4" cross-section. Our test riders particularly liked these tyres for their good grip. Mounted on wide rims, these tyres ensure grip, traction and comfort on any terrain.

The BROSE T Aluminium central motor is specially designed for high altitude mountain biking:, - 70 Nm torque to handle large obstacles and steep gradients, - metal housing for maximum durability, - belt for an ultra-quiet motor, - sealed bearings to hold up to tough environments while mountain biking

Our Rockrider mountain bike team has designed a battery that locks in place with a simple lever. Child's play! This locking system stops the battery getting shaken when you go adventuring on rough terrain. There is also a lock in case you want to stop your battery getting stolen. For example, if you park your bike in the street.