Compare bikes: Compare Btwin Rockrider ST 900 (2020) vs. Rockrider ST 520 V2 (2020) - Findabike

The new aluminium chainset has a 152 mm crank that is suited to the child's leg length. This light chainset allows you to start pedalling more easily.The double guard over the chain stops it jumping.

Our engineers have designed a new aluminium frame. Durable, lightweight and responsive: designed for tackling any obstacles when out mountain biking. - Top tube length: 479.3 mmSeat tube length: 345 mmChainstay length: 415 mmSeat post length: 370 mmHead angle: 68.2°

It isn't always easy to get the right position on a mountain bike. Our designers created a frame that's easy to get onto.The CGF frame (Comfort Geometry Frame), made of 100% aluminium, provides excellent comfort and manoeuvrability.The incline on this women's model, paired with the 60 mm stem, keeps your back straighter, while the shorter chain stays give you good agility on corners.No more aching back or neck!

Take on new challenging terrain (roots, stones, gravel, etc.) with ease thanks to the travel of the front suspension fork. Suntour fork with 50 mm of travel.

You can adjust how stiff the suspension is using the dial on the fork based on your weight (riders over 45 kg) so that roots and stones are easier to get past. This UFIT technology is patented and exclusive to Decathlon. Simply turn the dial!The 80 mm front suspension is designed for slightly uneven trails, helping you to get past your first obstacles with no problems. Its mechanical spring system guarantees reliability and easy maintenance.

The double-walled aluminium rims are light and durable.For transporting the bike, we've made it easy to attach/detach the front and rear wheels. They are equipped with a quick-release system.The tyres use SkinWall technology. This process allows you to reduce their weight, therefore increasing performance, grip and comfort.24-inch 1.7 to 2.2 cross-section inner tube with Schrader valve. Pressure indicated on the tyre sidewall (between 2 and 3.5 bar).

Brake effectively thanks to the mechanical disc brakes at the front and rear.The disc brake acts on the wheel axle to deliver powerful braking under any conditions (dry, wet, muddy, etc.).

The Tektro TKD 68 160 mm double disc brakes provide powerful, progressive braking at the front and rear. The aluminium Tektro brake levers are light, precise, and easy to hold. The brakes can be applied using only two fingers.We recommend that you have your brakes checked at least once a year.The brake levers are closer on the ST 520 women's mountain bike for a more comfortable position!

The ST 520's saddle fixing (welded) prevents any saddle movement during your mountain bike rides.Want an even comfier saddle? Add a saddle cover. Adjust your saddle height quickly and without tools using the quick-adjust lever.

The women's ST 520 comes with platform MTB pedals mounted on bearings, made from hard resin for light weight and safety.If your foot slides on the pedal, there's less risk of injury.