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Btwin ST520, Mountain Bike, 27.5"

Sale price: $399.00 Regular price: $499.00

Raised position., stem can be raised up to 1.18 in., ergonomic saddle: comfort that also yields greater efficiency. 27.5" wheels, double disc brakes, 24 speeds.

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Sale price: $399.00 Regular price: $499.00

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San Francisco, 735 Market St. Options

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Model: 8511143

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Product Features

A photo of the Btwin ST520, Mountain Bike, 27.5" in use

Btwin ST520, Mountain Bike, 27.5" | sporty mountain bike rides.

Raised position., stem can be raised up to 1.18 in., ergonomic saddle: comfort that also yields greater efficiency. 27.5" wheels, double disc brakes, 24 speeds.

Cycling comfort

Raised position. Ergonomic saddle. Height-adjustable stem. Soft-touch grips.

Efficiency

CGF Evo aluminum frame. 24-speed SRAM X3. Light, 27.5" Aero Trail Evo wheels.

Precision

Dual disc brakes. Easy handling frame geometry. Tires have good grip in turns.

Easy to use

Innovative fork with easy adjustment based on rider's weight.

Product Customer Reviews

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29 Reviews
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Btwin ST520, Mountain Bike, 27.5
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ST520

Attractive, well kited bike for the price, comfortable and fast for geometry.

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CRACKING BIKE

The bike arrived very quickly which was great, been out on it a few times and it is very nice to ride, looking forward to the weekend now to take it out again.

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VALUE FOR MONEY

Very good lite quality of bike for price £280 compare to rip off Halfords smooth ride great part's with disc brakes always recommend decathlon bikes

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NICE BIKE

Good reviews and a good economical bike I’ve really enjoyed riding it with slick gears

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STEFAN

The best

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GREAT BIKE

My Son very pleased with the quality of the bike that he choose for me to buy for him. High rating of the gears and brakes on the bike.

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MR

Great bike for the price smooth ride

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EXCELLENT VALUE

Great service too, picked it up 2 hours after i'd ordered it!

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GREAT BIKE AT A GOOD PRICE

Got this for my 14 year old son. He loves it.

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BLACK BIKE

A good bike for the price.

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GREAT BIKE FOR SUCH A PRICE

Went to pick up my bike from decathlon thinking it would be in a cardboard box but, was surprised to find the cycle was fully prepared for me and handed over to me by polite and pleasent staff.

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GREAT BIKE FOR THE PRICE. BEATS HALFORDS HANDS DOW

I'm not a believer in paying big bucks for a bike so bought this on spec from the website. I love the bike. Smooth gears and disc brakes for £280 delivered. Suits my needs perfectly doing grueling Hilly rides to keep fit. Great on the flat too. What more do you want ...... 5 stars from me.

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GOOD

T

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EXCELLENT BIKE

Really pleased with the bike. It is comfortable to ride on long trails on and off road. The gear changes are quick and precise and the brakes work really well in all the conditions I have ridden in. The overall finish and styling is superb.

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GREAT BIKE FOR THE PROCE

Having ridden much more expensive mountain bike over the years (Cube and Vitus), I was a bit apprehensive about getting this... 6 months later and it's handled everything I've thrown at it really well. It doesn't have hydraulic disc brakes, but the stopping power of the mechanical brakes are pretty good and they have performed well off-road. The upright position is comfortable and the only thing I've changed is the pedals. If you are looking for something that you can take off-road every now and again, this is a great bike for the price!

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ST 520 V2 ROCKRIDER

To say im pleased with my purchase is a huge understatement, the ROCKRIDER 520 is a lot of bike for its money, it's robust, well balanced and slips through its gearing with all the slickness you would hope for. This combined with a first class customer experience in store,make me a very happy chap!

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D+

Super bike

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BRILLIANT

Good cycle now it’s been back to Bolton Decathlon to be sorted out

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LOVE THIS BIKE

Doing 80 miles a week to and from work what a bike love it

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BRILLIANT

Lad loves the bike

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BRILLIANT BIKE, MUCH BETTER THAN HALFORD!!!!

Brilliant bike

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THIS BIKE IS WORTH THE MONEY YOU PAY FOR IT

This Bike Is The Best Bike I Have Ever Had, And I Am Ever So Lucky To Have This EXCELLENT Bike

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GOOD BIKE

This bike is excellent to ride

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GREAT BIKE FOR TEENAGE SON

We got this bike for my teenage son as he had grown too big for his old bike. The staff member at Rushden Lakes was excellent and helped us to choose the right size for him. He loves the bike, it is solid and well built, has great adjustable front suspension and the brakes are very responsive. Excellent value for money

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MOUNTAIN BIKE REVIEW

Product arrived on time, well packaged and seemingly in good condition. Have only been out for 1 ride so far but it felt good to me. Need to fiddle around with the set up of the gears as I was struggling to get into the highest cog on the front chain ring - but imagine this should be fairly simple to fix.

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GOOD FOR PRICE

after 3000 miles first big service

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ROCKRIDER 520

Nice entry level Bike. Pleasantly surprised with the stopping power of the cable operated disc brakes compared to my previous bikes Hydraulic versions.

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NOT A HAPPY BIKER

Was having fun on a 30 year old bike Got this one not for mountain work just to potter in the forest paths 1st the chain starting coming of when I was pitting under pressure causing me to get a very painfully leg Went back to get the crank replaced because apparently the wrong one was fitted in manufacturing. This was fine so took it out today and the chain jamed between cog and frame this was not fun when in the woods back end of no where And in a puncher on the brilliant tyres I think I may be going back to may old bike at least I had fun on it.

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POOR PAINT AND GEAR SYSTEM

Bought this bike a week ago came with mark already on frame ignored this, been out once for an hour. Gears slipped twice and totally wrecked frame took a massive chunk out like paper. Took it to Decathalon and told not to use all gears as this is a common fault called gear crossing? Then got it home and noticed main frame under seat where the guy gently put bike on stand to alter had caused it to shed paint. Hate to think what bike will look like in another week of riding will be looking to return for a full refund. Gears not good and paint of poor quality.

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Size Guide

Size Guide Visual

Additional Product Information

Composition

Bike frame

  • 100% Aluminum

Design

The RockRider 520 was designed and created in Suzhou, China, by a team of experts and cycling enthusiasts dedicated to designing our MTB Sport Touring line. Production was also done near Suzhou to be as close to our Decathlon stores as possible.

Frame

Rockrider CGF Evo (Comfort Geometry Frame) 6061 aluminum frame for 27.5" wheels. Comfortable seating position thanks to raised steering. Seat is 5 times more flexible than a standard frame thanks to a narrow 1.07-in. seat post. Low bottom bracket: helps keep the mountain bike stable in turns, and makes it easier to place foot on the ground. Open steering angle (69.5°): keeps mountain bike stable while riding. Short rear wheel base: bicycle is easy to turn. LIFETIME WARRANTY on the frame!

Front suspension

B'Twin U-Fit 80 fork, with 3.15 in. of travel and an innovative fork stiffness adjustment based on the rider's weight (121 to 230 lbs.). Durable thanks to the materials and fabrication processes used. Equipped with a mechanical spring and elastomer stoppers for maximum reliability and minimum maintenance.

Rear suspension

No rear suspension.

Drivetrain

SRAM S200 triple-chainring chainset (22/32/42 teeth). SRAM X3 8-speed rear derailleur. Microshift MS22 front derailleur. SRAM X4 shifters with speed indicators. SRAM PG820 cassette, 8 cogs, 11 to 32 teeth.

Brakes

Tektro aluminum brake levers: lightweight and precise. Front and rear Hayes MX5 mechanical disc brake calipers: powerful, progressive braking, even in rainy and muddy conditions.

Handlebar/stem/steering/grips

B'Twin Sport Oversize aluminum handlebar; 25.9 in. (Size S and M), and 26.7 in. (L and XL). Exclusive B'Twin aluminum stem, 70 mm (size S and M), and 80 mm (size L). Stem can be raised by up to 1.2", with 5 settings (+0", +0.3", +0.6", +0.9", +1.2"). Semi-integrated A-headset—better sealed and integrated style. B'Twin Sport handles with grooves, 4.72 in. long: genuine comfort while riding.

Wheels

Aero Trail Evo aluminum wheels with double-walled rims: lightweight, stiff, and durable. 27.5" diameter: the best balance of comfort and performance. Designed with 28 spokes to reduce weight while still ensuring rigidity and strength.

Tires

Exclusive B'Twin All Terrain Dry 27.5" x 2.0 tires with a central tread specially designed for fast performance. Side lugs provide traction in turns. Also includes a chart showing recommended pressure levels depending on the rider's weight (see markings on tire sidewalls).

Saddle / seat post

Exclusive B'Twin Ergofit Evo saddle offers outstanding comfort thanks to its wider "Hammock" cut and good distribution of pressure points regardless of the rider's pelvis width. B'Twin Sport seat post in aluminum for less weight. 1.1". diameter provides the seat with a natural flex that's 5 times greater than a classic seat post. 400 mm long, offering a broad adjustment range.

Pedals

Bicycle comes with mountain bike platform pedals with bearings, made from hard resin for lower weight and greater safety (less aggressive in case of pedal that slips).

Weight

31.63 lbs in S without pedals. 31.8 lbs in M without pedals. 32.1 lbs in L without pedals.

Accessories

Frame can take a bottle cage, saddle bag, mud guard, stand, pannier rack.

User guide & bike assembly

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Origin

Imported

Warning - california prop 65

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Product testing

We also recommend that beginners wear cycling shorts with a protective pad and/or a gel saddle cover to reduce soreness.

Storage instructions

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

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