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Product description

This electric mountain bike is designed for MTB rides in the mountains.

Looking for an electric bike for riding in the mountains? This long-distance MTB has a 3-hour battery life, and a 70 Nm torque motor that automatically assists you to tackle any challenge with ease.

Autonomy

Ride for up to 68 km

Power

70 Nm torque and 500 W max power central motor

Control

Enjoy: raised position, 120 mm suspension, very wide tyres, Ergofit saddle.

Cushioning

Control your trajectory: ROCKSHOX Judy fork, extra wide HUTCHINSON tyres

ROCKRIDER

27.5"+ Electric Hardtail MTB Bike E-ST 900 - Grey

Sale price1,375.000 BD
Sold out

Size Guide

MEN SIZE GUIDE 

 

How to measure:

  • Head size: Wrap a tape measure horizontally around your head just below your eyebrows.
  • Chest size: Wrap a tape measure horizontally around the widest part of your chest.
  • Waist size: Wrap a tape measure horizontally around the widest part of your waist.
  • Hand size: Wrap a tape measure horizontally around your hand, starting from your thumb.
  • Shoe size: Place your heels flush against a wall. Place a heavy object (such as a book) against your toes. Measure the distance between the wall and the object.

TOPS (T-SHIRT, PULLOVER, JACKET)
 Size XS S M L XL 2XL 3XL 4XL
Chest (cm) 84-87 88-91 92-95 96-103 104-113 114-123 124-135 136-146

 

BOTTOMS (SHORTS, PANTS, BOARDSHORTS)
 Size XS S M L XL 2XL 3XL
Hips (cm) 84-86  87-91  92-97 98-104 105-111 112-118 119-126

 

SWIMWEAR
 Size S M M-L L L-XL XL XL-2XL 2XL
Hips (cm) 84-87 88-91 92-95 96-103 104-113 114-123 124-135 136-146

 

WOMEN SIZE GUIDE

 

How to measure:

  • Head size: Wrap a tape measure horizontally around your head just above your eyebrows.
  • Chest size: Wrap a tape measure horizontally around the widest part of your chest.
  • Band size: Wrap a tape measure horizontally around your torso just below your breasts.
  • Waist size: Wrap a tape measure horizontally around the widest part of your waist.
  • Hip size: Wrap a tape measure horizontally around the largest part of your hips.
  • Hand size: Wrap a tape measure horizontally around your hand, starting from your thumb.
  • Shoe size: Place your heels flush against a wall. Place a heavy object (such as a book) against your toes. Measure the distance between the wall and the object.
    TOPS (T-SHIRT, PULLOVER, JACKET)
    Size 3XS 2XS XS S M M-L L L-XL XL XL-2XL 2XL
    Chest (cm) 76-79 80-83 84-87 88-91 92-95 96-99 100-103 104-107 108-113    114-118 119-123
     
    BOTTOMS (SHORTS, PANTS)
     Size 3XS 2XS XS S M L XL 2XL 3XL
    Hips (cm) 81-85 86-90 91-96 97-102 103-108 109-114  115-120 121-128 129-136

     

    BRA
    Size 70A 70B 70C 70D 75A 75B 75C 75D 75E 80A 80B 80C 80D 80E 85B 85C 85D 85E
    Chest size (cm) 80-86 80-86 80-86 80-86 86-92 86-92 86-92 86-92 86-92 92-100 92-100 92-100 92-100 92-100 100-106 100-106 100-106 100-106

     

    SWIMWEAR
    Size XS S M M-L L L-XL XL XL-2XL 2XL
    Hips (cm) 90-93 94-97 98-101 102-105 106-109 110-113 114-119 120-125 126-131

     

    KIDS SIZE GUIDE

     

     

    How to measure:

    • Clothing size: Stand upright and place your bare heels flush against a wall. Measure the distance between the bottom of your foot and the top of your head.
    • Head size: Wrap a tape measure horizontally around your head just above your eyebrows.
    • Hand size: Wrap a tape measure horizontally around your hand, starting from your thumb.
    • Shoe size: Place your heels flush against a wall. Place a heavy object (such as a book) against your toes. Measure the distance between the wall and the object.

     

      APPAREL
      Age 3 Months 6-9 Months 9-12 Months 18 Months 2 Years 3 Years 4 Years 5 Years 6 Years 8 Years 10 Years 12 Years 14 Years
      Height (cm) 56-63 64-70 71-76 77-82 83-89 90-97 98-104 105-114 115-124 125-132 133-142 143-152 153-162

       

      SHOES SIZE GUIDE

      MEN SHOES
      US Size 6.5 7 7.5 7.5 8 8.5 9 9.5 9.5 10 10.5 11 11.5 11.5 12 12.5 13
      EU Size 39 39.5 40 40.5 41 41.5 42 42.5 43 43.5 44 44.5 45 45.5 46 46.5 47
      Foot Length (in) 1/2 3/4 10 10 10 1/4 10 1/2 10 1/2 10 1/2 10 3/4 10 3/4 11 11 1/4 11 1/4 11 1/2 11 1/2 11 1/2 11 3/4

       

      WOMEN SHOES
      US Size 4 4.5 5 5.5 5.5 6 6.5 7 7.5 7.5 8 8.5 9 9 9.5 10 10.5
      EU Size 34 34.5 35 35.5 36 36.5 37 37.5 38 38.5 39 39.5 40 40.5 41 41.5 42
      Foot Length (in) 1/2 1/2 1/2 3/4 3/4 9 1/4 1/4 1/2 1/2 1/2 3/4 10 10 10 1/4 10 1/2 10 1/2

       

      KIDS SHOES
      US Size 4.5C 5C 5.5C 6C 7C 7.5C 8.5C 9C 10C 11.5C 12.5C 13C 1 2 2.5 3.5 4 5
      EU Size 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
      Foot Length (in) 3/4 5 1/4 1/2 3/4 6 1/4 1/2 3/4 7 1/4 1/2 3/4 8 1/4 1/2 3/4 1/4

       

      GEAR SIZE GUIDE

      KIDS BIKES
      Bike size 12" 14" 16" 20" 24"
      Kids height (cm) 75-​90 90-​105 105-120 120-135 135-155
      kids height (ft) 2'5'' - 3' 3' - 3'5'' 3'5'' - 3'11'' 3'11''- 4'5'' 4'5'' - 5'1''

       

      ROAD BIKES
      Bike size 48 (XS) 51 (S) 54 (M) 57 (L) 60 (XL)
      Your height (cm) 135-150 150-165 165-176 176-184 184-195

       

      MOUNTAIN BIKES
      Bike size XS S M L XL
      Your height (cm) 135-150 150-165 165-176 176-184 184-195

       

      SKIS
      Ski size 115-130 125-140 130-145 135-150 135-155 145-165 150-170 155-175 160-180 165-185 170-190 175-195 180-200
      Your height (cm) 132 137 142 147 152 158 163 168 173 178 183 188 193

       

      SNOWBOARDS
      Snowboard size 128-136 133-141 139-147 144-152 149-157 154-162 159-167 160+ 160+ 160+
      Your height (cm) 147 152 158 163 168 173 178 183 188 193
      Your weight (lb) 50-55 55-60 60-65 65-70 70-75 75-80 80-85 85-90 90-95 95-100

       

      ACCESSORIES SIZE GUIDE

      KIDS GLOVES
      Glove size 4 Years 6 Years 8 Years 10 Years 12 Years 14 Years
      Hand size (cm) 13.9-14.9 14.9-15.9 15.9-16.9 16.9-17.8 17.8-18.6 18.6-19.5

       

      ADULT GLOVE
      Glove size XS S M L XL 2XL 3XL
      Hand size (cm) 20.3-20.8 20.9-21.4 21.5-22.1 22.2-22.7 22.8-23.4 23.5-24 24.1-24.7

       

      BOXING GLOVES
      Glove size 6oz 8oz 10oz 12oz 14oz
      Your weight (lb) 77-99 99-143 143-172 172-198 >198

      Product description

      This electric mountain bike is designed for MTB rides in the mountains.

      Looking for an electric bike for riding in the mountains? This long-distance MTB has a 3-hour battery life, and a 70 Nm torque motor that automatically assists you to tackle any challenge with ease.

      Autonomy

      Ride for up to 68 km

      Power

      70 Nm torque and 500 W max power central motor

      Control

      Enjoy: raised position, 120 mm suspension, very wide tyres, Ergofit saddle.

      Cushioning

      Control your trajectory: ROCKSHOX Judy fork, extra wide HUTCHINSON tyres

      Description

      This electric mountain bike is designed for MTB rides in the mountains.

      WHAT SIZE MOUNTAIN BIKE TO CHOOSE?

      Please note, for size S, the minimum height is 1.60 m and not 1.50 m as indicated in the drop-down menu grid. If you are on the edge between 2 sizes: Choose the smaller size for easier steering (easier to handle) and comfort (straighter back). Choose the larger size for easier pedalling with a more stretched out position (position more suited to performance)

      IS ELECTRIC MTB A SPORT?

      You have to pedal to go forward! The electric assistance boosts your pedalling by 320%, helping you ride over obstacles. You'll get to enjoy longer MTB rides. The motor stops when you stop pedalling. The walking mode compensates for the weight of the bike when you need to put your feet down.

      A WORD FROM THE TEAM

      Our team of mountain bike enthusiasts created this E-ST 900 electric mountain bike at our B'Twin Village in Lille, France. We designed and tested the E-ST 900 MTB by involving MTB riders at every stage of the project.

      STURDY, PLAYFUL FRAME

      The frame of the Rockrider E-ST900 electric MTB is made of 6061 aluminium with hydroformed tubes. Why? The battery sits snugly on the frame to improve the robustness of this electric mountain bike. The forged aluminium parts make it compatible with the new 27.5"+ tyre format (wider than the 27.5") in the rear, while remaining easy to manoeuvre. We've kept a frame geometry with short bases for easier steering.

      MOTOR WITH 70NM TORQUE

      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 - and sealed bearings to withstand the sometimes adverse weather conditions of mountain biking

      SAMSUNG BATTERY CELLS

      Our battery is equipped with SAMSUNG SDI cells, renowned for their high level of reliability and safety.

      BATTERY LOCK

      Our Rockrider mountain bike team has designed a battery that locks in place with a simple lever. Child's play! This locking system prevents the battery vibrating when riding on rough terrain. A key lock is also installed if you want to protect your battery from theft. For example, if you park your bike in the street.

      CONTROL SCREEN

      A discreet LCD control screen. The screen is right next to your left grip so you don't have to let go of the handlebar to choose from the 4 assistance modes available: Eco+, Economy, Standard, Boost. You'll also find a host of useful information: -Assistance level -Battery level -Speed (current, average, maximum) -Remaining battery life -Distance covered (total and trip)

      4 ASSISTANCE MODES

      Mode 0 - Deactivated The battery is not used. Mode 1 - Economy +40%: Extend your rides while conserving battery life. Ideal when you want a little push on small gradients. Mode 2 - Economy +80%: Gain power. A perfect helping hand for keeping up with other mountain bikers. Mode 3 - Standard +160%: This is the most versatile mode. Climb any slope without getting too tired and without using too much power. Mode 4 - Boost +320%

      ROCKSHOX FRONT SUSPENSION

      Ride over obstacles (roots, pebbles, stones, etc.) easily thanks to the Rockshox JUDY fork with 120 mm of travel. This fork has: - a thru axle and conical pivot for more durability. - pneumatic spring for optimal adjustment based on your weight - rebound adjustment and lockout for better control, depending on the terrain.

      SINGLE CHAINRING DRIVETRAIN

      The E-ST900 electric bike is equipped with a single chainring and ChainFlow 3D anti-drop technology to prevent chain drops. A single shifter on the right handlebar makes it easy to shift between the 10 speeds. In detail: - ChainFlow anti-derailment 34-tooth chainring - SHIMANO DEORE M6000 Shadow+ 10-speed rear derailleur with long cage - SHIMANO DEORE M6000 right shifter - SHIMANO DEORE 10-cog cassette (11-42 teeth) - KMC E10 Turbo special e-bike chain

      27.5+ Sunringle Duroc 40 Wheels

      These wheels were specially designed for this mountain bike: - 36 mm rims (width between brackets) and 32 spokes at the front and rear for greater durability and a good hold on wide (2.8") tyres. - BOOST format thru axles (12x148 rear, 15x110 front) for greater durability - Aluminium hubs with sealed bearings. - TUBELESS READY rims: you will need TUBELESS tyres, specific Presta valves, and puncture sealant.

      HUTCHINSON TYRES

      So you feel safe on any terrain, and to provide traction suited to your motor, the E-ST900 mountain bike is equipped with Hutchinson Taipan Koloss 27.5+ tyres with a 2.8" cross-section. Our test riders particularly liked these tyres for their grip on the ground. Mounted on wide rims, these tyres ensure grip, traction, and comfort on any terrain.

      HYDRAULIC DISC BRAKES

      No matter the conditions you ride in (dry, muddy, wet), the Tektro TKD32 hydraulic disc brakes on the front and rear provide powerful, progressive braking. Oversized 180mm diameter discs provide even more power.

      HANDLEBARS, STEM, GRIPS

      The adjustable stem brings the E-ST 900 controls to your hands. The all-aluminium Rockrider stem is 70 mm (size S), 80 mm (size M/L), or 90 mm (size XL) and can be raised to 5 adjustment intervals: + 0mm, + 7.5mm, + 15mm, + 22.5mm, + 30mm. In detail: - 720mm oversize ROCKRIDER SPORT aluminium handlebar - ROCKRIDER SPORT "soft touch" ergonomic grips for good grip and a comfortable feel

      Saddle

      Since your mountain bike rides will get longer and longer, it is important to sit comfortably. So our teams designed the exclusive ROCKRIDER Ergofit Pro 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 post ensures compatibility with most adjustable and suspended seat posts on the market.

      Platform pedals

      The bike comes with 520 Grip MTB platform pedals (ref. 8487130) with a wider pedalling surface and more pronounced dots for better grip on the pedal.However, if you are looking for improved performance when pedalling and better control of the bike when cycling, we recommend replacing them with clipless pedals with platforms or wide aluminium platform pedals.

      Accessories

      Your E-ST900 mountain bike is fitted with a bell, lights, wheel reflectors and pedals. The frame is compatible with: - front and rear mudguards - stand - bottle cage (on the horizontal tube) - saddle pouch - rear pannier rack (fixed onto the seat stays or special mounts for wide bikes, 148 mm gap for the rear wheel & 2.8" fat tire) - child seat ...

      OUR ADVICE FOR YOUR FIRST RIDES

      Tip no.1 When mountain biking, there is always the risk of a fall: don't forget to wear a helmet. Tip no. 2 A puncture could happen at any time, so always remember to take a repair kit and a 6 mm Allen key for removing your wheels. Tip no.3 If you don't want to stop to drink, bring water in a bottle or water bladder to access it while riding.

      Care advice

      Leave your battery on the bike when washing using a hose. This will protect the connectors from rusting.

      Looking for an electric bike for riding in the mountains? This long-distance MTB has a 3-hour battery life, and a 70 Nm torque motor that automatically assists you to tackle any challenge with ease.

      Autonomy

      Ride for up to 68 km

      Power

      70 Nm torque and 500 W max power central motor

      Control

      Enjoy: raised position, 120 mm suspension, very wide tyres, Ergofit saddle.

      Cushioning

      Control your trajectory: ROCKSHOX Judy fork, extra wide HUTCHINSON tyres

      This electric mountain bike is designed for MTB rides in the mountains.

      This electric mountain bike is designed for MTB rides in the mountains.

      WHAT SIZE MOUNTAIN BIKE TO CHOOSE?

      Please note, for size S, the minimum height is 1.60 m and not 1.50 m as indicated in the drop-down menu grid. If you are on the edge between 2 sizes: Choose the smaller size for easier steering (easier to handle) and comfort (straighter back). Choose the larger size for easier pedalling with a more stretched out position (position more suited to performance)

      IS ELECTRIC MTB A SPORT?

      You have to pedal to go forward! The electric assistance boosts your pedalling by 320%, helping you ride over obstacles. You'll get to enjoy longer MTB rides. The motor stops when you stop pedalling. The walking mode compensates for the weight of the bike when you need to put your feet down.

      A WORD FROM THE TEAM

      Our team of mountain bike enthusiasts created this E-ST 900 electric mountain bike at our B'Twin Village in Lille, France. We designed and tested the E-ST 900 MTB by involving MTB riders at every stage of the project.

      STURDY, PLAYFUL FRAME

      The frame of the Rockrider E-ST900 electric MTB is made of 6061 aluminium with hydroformed tubes. Why? The battery sits snugly on the frame to improve the robustness of this electric mountain bike. The forged aluminium parts make it compatible with the new 27.5"+ tyre format (wider than the 27.5") in the rear, while remaining easy to manoeuvre. We've kept a frame geometry with short bases for easier steering.

      MOTOR WITH 70NM TORQUE

      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 - and sealed bearings to withstand the sometimes adverse weather conditions of mountain biking

      SAMSUNG BATTERY CELLS

      Our battery is equipped with SAMSUNG SDI cells, renowned for their high level of reliability and safety.

      BATTERY LOCK

      Our Rockrider mountain bike team has designed a battery that locks in place with a simple lever. Child's play! This locking system prevents the battery vibrating when riding on rough terrain. A key lock is also installed if you want to protect your battery from theft. For example, if you park your bike in the street.

      CONTROL SCREEN

      A discreet LCD control screen. The screen is right next to your left grip so you don't have to let go of the handlebar to choose from the 4 assistance modes available: Eco+, Economy, Standard, Boost. You'll also find a host of useful information: -Assistance level -Battery level -Speed (current, average, maximum) -Remaining battery life -Distance covered (total and trip)

      4 ASSISTANCE MODES

      Mode 0 - Deactivated The battery is not used. Mode 1 - Economy +40%: Extend your rides while conserving battery life. Ideal when you want a little push on small gradients. Mode 2 - Economy +80%: Gain power. A perfect helping hand for keeping up with other mountain bikers. Mode 3 - Standard +160%: This is the most versatile mode. Climb any slope without getting too tired and without using too much power. Mode 4 - Boost +320%

      ROCKSHOX FRONT SUSPENSION

      Ride over obstacles (roots, pebbles, stones, etc.) easily thanks to the Rockshox JUDY fork with 120 mm of travel. This fork has: - a thru axle and conical pivot for more durability. - pneumatic spring for optimal adjustment based on your weight - rebound adjustment and lockout for better control, depending on the terrain.

      SINGLE CHAINRING DRIVETRAIN

      The E-ST900 electric bike is equipped with a single chainring and ChainFlow 3D anti-drop technology to prevent chain drops. A single shifter on the right handlebar makes it easy to shift between the 10 speeds. In detail: - ChainFlow anti-derailment 34-tooth chainring - SHIMANO DEORE M6000 Shadow+ 10-speed rear derailleur with long cage - SHIMANO DEORE M6000 right shifter - SHIMANO DEORE 10-cog cassette (11-42 teeth) - KMC E10 Turbo special e-bike chain

      27.5+ Sunringle Duroc 40 Wheels

      These wheels were specially designed for this mountain bike: - 36 mm rims (width between brackets) and 32 spokes at the front and rear for greater durability and a good hold on wide (2.8") tyres. - BOOST format thru axles (12x148 rear, 15x110 front) for greater durability - Aluminium hubs with sealed bearings. - TUBELESS READY rims: you will need TUBELESS tyres, specific Presta valves, and puncture sealant.

      HUTCHINSON TYRES

      So you feel safe on any terrain, and to provide traction suited to your motor, the E-ST900 mountain bike is equipped with Hutchinson Taipan Koloss 27.5+ tyres with a 2.8" cross-section. Our test riders particularly liked these tyres for their grip on the ground. Mounted on wide rims, these tyres ensure grip, traction, and comfort on any terrain.

      HYDRAULIC DISC BRAKES

      No matter the conditions you ride in (dry, muddy, wet), the Tektro TKD32 hydraulic disc brakes on the front and rear provide powerful, progressive braking. Oversized 180mm diameter discs provide even more power.

      HANDLEBARS, STEM, GRIPS

      The adjustable stem brings the E-ST 900 controls to your hands. The all-aluminium Rockrider stem is 70 mm (size S), 80 mm (size M/L), or 90 mm (size XL) and can be raised to 5 adjustment intervals: + 0mm, + 7.5mm, + 15mm, + 22.5mm, + 30mm. In detail: - 720mm oversize ROCKRIDER SPORT aluminium handlebar - ROCKRIDER SPORT "soft touch" ergonomic grips for good grip and a comfortable feel

      Saddle

      Since your mountain bike rides will get longer and longer, it is important to sit comfortably. So our teams designed the exclusive ROCKRIDER Ergofit Pro 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 post ensures compatibility with most adjustable and suspended seat posts on the market.

      Platform pedals

      The bike comes with 520 Grip MTB platform pedals (ref. 8487130) with a wider pedalling surface and more pronounced dots for better grip on the pedal.However, if you are looking for improved performance when pedalling and better control of the bike when cycling, we recommend replacing them with clipless pedals with platforms or wide aluminium platform pedals.

      Accessories

      Your E-ST900 mountain bike is fitted with a bell, lights, wheel reflectors and pedals. The frame is compatible with: - front and rear mudguards - stand - bottle cage (on the horizontal tube) - saddle pouch - rear pannier rack (fixed onto the seat stays or special mounts for wide bikes, 148 mm gap for the rear wheel & 2.8" fat tire) - child seat ...

      OUR ADVICE FOR YOUR FIRST RIDES

      Tip no.1 When mountain biking, there is always the risk of a fall: don't forget to wear a helmet. Tip no. 2 A puncture could happen at any time, so always remember to take a repair kit and a 6 mm Allen key for removing your wheels. Tip no.3 If you don't want to stop to drink, bring water in a bottle or water bladder to access it while riding.

      Care advice

      Leave your battery on the bike when washing using a hose. This will protect the connectors from rusting.

      Looking for an electric bike for riding in the mountains? This long-distance MTB has a 3-hour battery life, and a 70 Nm torque motor that automatically assists you to tackle any challenge with ease.

      Autonomy

      Ride for up to 68 km

      Power

      70 Nm torque and 500 W max power central motor

      Control

      Enjoy: raised position, 120 mm suspension, very wide tyres, Ergofit saddle.

      Cushioning

      Control your trajectory: ROCKSHOX Judy fork, extra wide HUTCHINSON tyres

      This electric mountain bike is designed for MTB rides in the mountains.

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