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Air shocks, hydraulic brakes.

All Bikes Cycling - Rockrider 520 S Full Suspension Mountain bike  B'TWIN - Bikes
Reference : 8208678
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B'TWIN Rockrider 520 S Full Suspension Mountain bike

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athletic MTB riders touring off-road in the country or mountains. Optimised brakes & weight: Take on the steep slopes.

To view our full range visit our mountain bikes category.


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Price in store £0.00 £450.00 **

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Home Delivery
free on orders over £70* - More information

Freedom of Return
find out more about our returns policy.

Safe payment
PayPal, Verified by VISA & MasterCard SecureCode.

Important: When you purchase a bike online, pedals are not fitted and the stem/bars are not adjusted. Please visit this video to see how to correctly set up your bike.

Life Time Warranty: B'TWIN makes the life time warranty for the frames, brackets, stems and rigid forks. Guaranteeing your Bike for life!

Product benefits

    • Lifetime warranty
    • B’TWIN guarantees the frame, stem, and handlebar for life.
    • Cushioning
    • 120mm fork with lockout & 120mm hydraulic air shock, for precision adjustment!
    • Low weight / lightweight
    • Air shocks: lighter and more precise. Lighter drive train. 14.9 kg in M.
    • Accuracy / precision
    • Precision suspension adjustable according to your weight. 27-speed SRAM X5.
    • Brake control
    • Tektro hydraulic disc brakes: powerful, progressive, robust.
  1. Guarantee : Frame, handlebar and stem have a lifetime guarantee.2 year guarantee for parts (excl. wearing parts)

Product information

M(1.65-1.75), L(1.75-1.85), XL(1.85-1.95)
Black / White / Red
Wheel size
26 inches
fork and shocks
14.7 kg in M without pedals

your reviews

4.8 / 5

10 reviews

9 people recommend this product

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Brilliant all rounder

Very well designed, great ergonomics + aesthetics



  (United Kingdom)

20-29 years old    Man

5 5

used for 3 to 6 months Brilliant bike, nice and lightweight but very strong structurally. Great suspension, hydraulic front forks and air rear. Nice crisp gear changes and the hydraulic brakes are precise and never give trouble (so far anyway). Good thick high grip tyres coupled with a very well designed frame and smooth ride make it very agile on tight mountain tracks, in fact it outperforms my friends £800 hardtail mtb.
Personally I feel this bike is very well designed both ergonomically and the aesthetics are very nice also.
Kudos to the designers, well done!

Excellent bike!

Steady ride, confortable and robust.

Lack of instructions/documentation when delivered.


  (United Kingdom)

30-39 years old    Man

5 5

used for 2 to 8 weeks I am using this bike for ~1 month now (70km various terrain). No problems so far (i have calibrated/double-checked all shop settings for brakes, shifting mechanisms, dampers, etc.). Tested it on high-speed lanes, mud, off-road tracks, steep climbs and descents - always surprises with good handling and soft ride. Well balanced for riding at high speeds ~ 50km/h, but the gear-shifting system will hardly allow you to go higher anyway. If you have never used Hydraulic brakes, than the RR6.5 braking performance may surprise you, delivering crisp and precise breaking: easy to use and lite on action.
As every MTB bike has (in my opinion) a poorly though mudguard attachment system

Fantastc value!

The rear shock is perfect for comfort and traction

toe clips useless. Zefal half toe clips better


  (United Kingdom)

20-29 years old    Man

5 5

used for 2 to 8 weeks This bike is excellent value for money! It won't be the fastest up the hill but has the perfect gear ratios for getting you there. With the rear shock I have added comfort on my lower back and more grip due to the tyre rear true rolling over obstacles rather than bouncing on a hardtail. The front shock works perfectly well for me who isn't trying to break the worlds fastest downhill time and simply wants to enjoy himself, not break my body in half! Fantastic kenda nevegal tyres, hydraulic disc brakes, bottom bracket is higher to clear more obstacles, good looking bike, gears shift superbly well, a pleasure to ride!

Fantastic value for money

Build quality, ride, looks, breaks

None for a sub £500 full sus


  (United Kingdom)

30-39 years old    Man

5 5

used for 3 to 6 months Getting back onto the saddle after over 10 years and after lots of test rides this is by far the best sub £500 bike

Fantastic value/performance combo

90% of the performance but 40% of the cost!

no rear lock-out


  (United Kingdom)

50-59 years old    

5 5

used for 2 to 8 weeks I bough two of these to replace the family's current aging hardtails.
Fantastic value and spec for the money - we were resigned to spending £1k on a full suspender at this spec so got two bikes for the price of one!
Done around 100km so far on a mixture of bridle paths, single track and forest trails - really smooth.
Well made and finished - paintwork and welds immaculate. Nice touches like the rubber protectors on the cables. Off to the Alps on Friday for a week's MTB'ing and have no worries about how this bike will perform.

Technical Information

  • 1

    Frame New 6061 aluminium oversize S.I.X frame with 120 mm rear wheel travel, based on a monopivot suspension system offering high sensitivity to small shocks but also gives the bike sturdy resistance to strong impacts. Weight= 2.7kg in size M, without shocks.

  • 2

    Fork Hydraulic Rockrider fork with 120mm of travel, with magnesium blade for lighter weight, with lockout at the top of the right damper for rolling terrain, and with easy adjustment of the pre-load (fork hardness) at the top of the left damper. A fork which has already proved itself.

  • 3

    Suspension X-Fusion E1 air shocks, lightweight, specifically adapted to the S.I.X. frame, easily adjustable to the rider's weight thanks to the schrader valve: a great balance between sensitivity and performance

  • 4

    Drive train Shimano Tourney front derailleur, Sram X5 rear shifter and derailleur: very good combination in terms of comfort of use, speed of gear changes, and reliability. Thanks to its 27 speeds and its quick gear changes, it is easy to find the right gear for each new type of terrain.
    Bottom bracket Suntour XCT triple chain wheels, 22/32/42 teeth. 9 speed Sram ESP 5.0 cassette, 11 x 34. Sram chain with quick-release.

  • 5

    Brakes Tektro Auriga Comp hydraulic disc brakes, offering high braking power while remaining progressive and easy to dose. 160 mm front and rear discs. Front and rear "postmount" callipers, directly screwed into the frame and the fork: gain in weight and ease of adjustment! Discover the power of hydraulic disc braking, you will not be disappointed!

  • 6

    Handlebar Oversize 640mm diameter Rockrider Sport aluminium handlebar, for better rigidity and stability on descents.

  • 7

    Stem Rockrider forged aluminium oversize diameter stem for more rigidity, with a 6º "backsweep" angle. The components are marked to help you find the best setting.

  • 8

    Steering Semi-integrated headset for improved watertightness, precision while riding, and a built-in look. 120 mm Rockrider mono-density grips.

  • 9

    Saddle Rockrider by Velo bi-material saddle with a sporty look. Comfortable, narrow saddle to avoid thigh chafing.

  • 10

    Seatpost Rockrider 29.8 mm diameter seat post, length: 350mm. Quick, tool-free saddle tightening.

  • 11

    Wheels Rockrider Sport wheels, with 32 hole double-walled aluminium rims: guaranteed shock and warp resistance, and lightweight! Aluminium hub compatible with disc brakes only.

  • 12

    Tyres Front and rear KENDA Nevegal 26x2.10 rigid bead tyre, known for its versatility: it behaves well on all types of surface, whatever the weather (dry or wet), thanks to its deep and well distributed tread, and its "Stick-E" rubber which provides good grip. Tyres with inner tube.

  • 13

    Pedals Wellgo platform pedals, with strapless toe-clips, for good foot support and the ability to remove your foot quickly should you lose balance.

  • 14

    Accessories Transparent self-sticking base protection: your frame paint need not fear!

  • 15

    Weight 14.8 kg in M without pedals

  • 16

    Electrical assistance No electric assistance.

Information / Concept / Technology

S.I.X. suspension system: Monopivot frame for greater simplicity and sensitivity, based on 120 mm travel.

Restricted use :

not designed for: BMX, Dirt, Freeride and Descent.

Stock advice

Store in a cool, dry place, away from corrosive products and salty air.

Care instructions:

We recommended reading and following the maintenance instructions provided with your Rockrider bike. The maintenance instructions and component settings are available on The safety visit (3 months after purchase) at your local store's workshop is FREE and RECOMMENDED.

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