ST 100 U-Fit 27.5" Mountain Bike - Black

€ 215.00
SKU: S300805 (2490945)
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Delivery in 3 to 4 working days
Product benefits
  1. Cycling comfort
    Enjoy touring: raised position, 80 mm suspension, hammock saddle, FLEX seat post
  2. Durability
    An ultra-strong MTB: double-walled rims, welded saddle, derailleur guard.
  3. Efficiency
    Light frame, 21 speeds, 27.5" wheels (XS 26"), tyres with low rolling resistance
  4. Directional control
    Control your ride: V-Brake pads, tyres with side lugs
  5. Lifetime warranty
    ROCKRIDER offers a lifetime warranty on the frame, handlebars and stem
Product feature
  1. WHAT OUR TEAM HAS TO SAY
    We created this ST 100 mountain bike at our B'Twin Village (Lille, France) especially for mountain biking enthusiasts. Recreational mountain bikers told us they wanted comfort, effectiveness and durability. Those features were our starting point as we designed, developed and tested the ST 100 mountain bike, with real riders involved throughout the project. We wanted riding with the ST 100 to be nothing but fun.
  2. A UNISEX MOUNTAIN BIKE
    The ST 100 mountain bike is designed for men and women alike. Carefully designed down to the smallest detail, with a noticeable slope on the top tube and a very wide range of sizes (from XS:1.45m to XL: 2.00m), the ST 100's CGF frame is not only light and comfy but is also unisex. To make the most of the improved comfort, the women of the Rockrider team recommend the 500 Women's Sports saddle that is adapted to women's morphology.
  3. How do you choose the right ST100 mountain bike size?
    Several sizes available: XS: between 1.40 m and 1.54 m S: between 1.55m and 1.64m M: between 1.65m and 1.74m L: between 1.75m and 1.84m XL: between 1.85m and 2.00m To adapt the bike to your height and size, try these tips: 1/ Sitting on the saddle, your should be able to touch the ground with the tips of your toes. 2/ To adjust the saddle height, your knee should be slightly flexed with the foot on the pedal in the lowest position. 3/ If you're between two sizes, choose the larger size.
  4. A light, comfortable, fun frame
    Because we've noticed that it's not always easy to get the right position on a mountain bike, our designers have created an entirely new frame that's easy to get onto for both men and women. The CGF frame (Comfort Geometry Frame) is 100% aluminium for optimal comfort and excellent manoeuvrability. The slope angle has been designed to keep your back straight whilst the low rear ensures the bike is very agile when turning.
  5. FRONT SUSPENSION FOR CUSHIONING LUMPS AND BUMPS
    The Suntour XCT 80mm front suspension is designed for slightly uneven trails and helps you overcome your first obstacles with no worries. Its design, based on a mechanical spring, is reliable and easy to maintain. It features U-Fit (weight adjuster) technology so that you can adjust the stiffness according to the rider's weight using a dial.
  6. REAR SUSPENSION: NONE
    This mountain bike has no rear suspension. It is a "semi-stiff" mountain bike: ideal for beginners. Compared with a full suspension bike (with rear suspension) the benefit is clear: it weighs much less so you waste less energy on flat terrain. A "semi-rigid" bike such as the ST 100 is a good choice for your first rides!
  7. DERAILLEUR & DRIVE TRAIN: CHANGE CHAINRING AND COG
    3 x 7 speed chainwheels, 21 speeds total! 2 easy-to-use grip shifters on the handlebars.Left (chainwheels): control ascents/descents. Right (speeds): more precise control over your pedalling. In detail: -Triple 22-, 32- and 42-tooth chainring + protection from grease -Shimano TY500 front derailleur -Shimano TY300 rear derailleur -SRAM MRX grip shifters with speed indicator -Shimano TZ500 7-cog, 14- to 28-tooth cassette -Wide, sturdy KMC Z51 chain
  8. STEM, HANDLEBAR, GRIPS: FOR GOOD HAND POSITIONING
    With a stem that tilts 10° upwards, the ST 100 gives you a raised, accessible, comfortable riding position. In detail: - 90mm (in sizes XS and S) or 110mm (in sizes M, L and XL) aluminium stem with an angle of 10° for maximum comfort - 620mm-wide steel handlebar, for stability and control -"Soft touch" grips for a firm yet soft and pleasant grasp.
  9. SADDLE: SIT COMFORTABLY!
    The saddle is welded to prevent any movement of the saddle as you cycle. Because your comfort is our top priority after safety, we've added the exclusive Ergofit saddle that's wider and with a hammock shape. Easily adjust the height of your saddle with the Flex steel seat post, either 350mm or 400mm long (according to the bike size). Its reduced diameter of 27.2mm provides your seat with natural flexibility, 30% more than a standard solution.
  10. V-BRAKES: CONTROL YOUR BRAKING
    Two V-Brake pads for effective braking. These brakes are composed of callipers that exert more or less pressure on the rim to slow or stop the rotation of the wheels. Thanks to the special design of the ST 100's aluminium brake levers, you only need two fingers to brake.
  11. 27.5" wheels & tyres for dry terrain: READY TO ROLL?
    Slow down without worrying about obstacles: small rocks, cracks, holes and bumps! The wheels of the ST 100 are tolerant and robust, with 27.5" double-walled 28-spoke rims (26" on the XS size). Because your first tours will be on dry ground, the Dry 27.5 x 2.0 tyres are most suitable. Their performance is optimised thanks to the rounded central section, whilst the side lugs provide good grip on turns.
  12. FLAT PEDALS
    The Rockrider ST 100 mountain bike comes with flat mountain bike pedals made from hard resin for lighter weight and greater safety. If your foot slides on the pedal, there's less risk of injury.
  13. EASILY TRANSPORT AND STORE YOUR MOUNTAIN BIKE
    Not all rides start on your doorstep. Need to take off the front wheel or transport it? To make it easier to mount / remove your front wheel, we've fitted it with a quick release system. There is a nut at the back to secure the bike and limit the risk of theft. You will need a spanner to remove the back wheel.A bike carrier will make your life easier if you want to avoid dirtying your car.
  14. ACCESSORIES
    Your ST 100 mountain bike is delivered with a derailleur guard, chainwheel guard (to prevent your clothes from getting dirty), bell, lights, wheel reflectors and pedals. The frame is compatible with: -Front and rear mudguards (Flash MTB or MTB 700) -Stand (500 Adult Base) -Bottle cage -Saddle pouch -Rear pannier rack -Child seat (Polisport Groovy frame mounted)
  15. COMFORT & SAFETY
    We recommend that beginners wear cycling shorts with a pad (foam in the shape of a saddle) or a gel saddle cover to reduce soreness. For longer rides, remember to take something to drink (e.g: a hydration bladder or bottle). In all circumstances, even for a short ride, wearing a helmet is essential!
  16. Comfort & safety
    We recommend that beginners wear cycling shorts with a pad (foam in the shape of a saddle) or a gel saddle cover to reduce soreness. For longer rides, remember to take something to drink (e.g: a water bladder or bottle). In all circumstances, even for a short ride, wearing a helmet is essential!
Product testing
  1. Composition
    Frame (for bike) : 100.0% Aluminium
  2. Storage advice
    After washing, rub with a dry cloth to remove all traces of moisture. Store your mountain bike in a cool, dry place, away from corrosive products and salty air.
  3. Product restrictions
    Not suitable for XC, All Mountain, Enduro and BMX.
  4. Product information
    Effective? Strong? Both please! Easily get through your first obstacles: lightweight aluminium frame and 27.5'' tyres on double-walled rims.
  5. Lab tested
    Our engineers always have real riders test all our products in real conditions. These tests round out our lab tests and let us validate all our products before they hit store shelves.