27.5" Mountain Bike ST 100 U-FIT - Black
Store Availability
Store availability
BENEFITS
Directional control
Control your trajectory: V-Brake pads, tyres with side knobs
Robustness
An ultra-strong MTB: double-walled rims, welded saddle, derailleur guard.
Lifetime warranty
ROCKRIDER offers a lifetime warranty on the frame, handlebar and stem.
Efficiency
Light frame, 21 speeds, 27.5" wheels (XS 26"), tyres with low rolling resistance
Cycling comfort
Enjoy touring: raised position, 80 mm suspension, hammock saddle, FLEX seat post
Instructions
Download it hereTECHNICAL INFORMATIONS
Which is the right size?
Several sizes available:
XS:between 1.40m and 1.54m
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 MTB to your height and size, try these tips:
1/ Sitting on the saddle, you 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.
UNISEX FRAME
With a very marked slope on the top tube and a wide range of sizes (from XS:1.40m to XL:2.00m),
The ST 100 mountain bike frame is UNISEX.
The ST 100 mountain bike exists with the same frame in a WOMEN'S version: fitted seat, narrower handlebar, shorter stem, fork with a more flexible spring, and brake levers that are closer together.
As a WOMAN, if you choose the MEN'S model, we recommend at least purchasing the WOMEN'S SPORT 500 saddle which is fitted to the female form.
A WORD FROM THE TEAM
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.
A LIGHTWEIGHT, COMFORTABLE, FUN FRAME
It isn't always easy to get the right position on a mountain bike. Our designers have created an entirely new frame that is easy to step over.
The 100% aluminium CGF frame (Comfort Geometry Frame) is both comfortable and easy to handle. The slope angle has been designed to keep your back straighter whilst the rear has been shortened to ensure the bike is very agile when turning.
Front suspension
The 80 mm front suspension helps you get started with overcoming obstacles on slightly uneven trails easily.
Easily adjust the hardness using U-Fit technology (weight adjuster). Simply set the number to your weight using the dial on the fork.
REAR SUSPENSION: None
This mountain bike has no rear suspension.
It is a "semi-stiff" mountain bike: perfect for beginners launching themselves into their first mountain bike touring rides.
Compared to a full suspension mountain bike (with rear suspension), the advantages are clear: the mountain bike is lighter; you spend less energy on flat ground.
DERAILLEUR & DRIVETRAIN:
3 x 7 speed chainrings, 21 speeds total!
2 easy-to-use grip shifters on the handlebar.
Left (chainrings): 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
-7-cog, 14- to 28-tooth cassette
-Wide, sturdy KMC Z51 chain
HANDLEBARS, STEM, GRIPS
With a stem that tilts 10° upwards, the riding position of the ST 100 is raised, accessible, and comfortable.
In detail:
-Aluminium stem, 90mm long, with a 10° angle for maximum comfort.
-620mm wide steel handlebar, for stability and control.
-Grips in "soft touch" material' for good grip and a soft comfortable feel.
Saddle
The saddle of the ST 100 is welded to prevent any movement of the saddle.
And because your comfort is our priority after your safety, we've added an exclusive wider Ergofit saddle with a hammock shape.
Easily adjust the height of your saddle with the Flex steel seat post (350mm or 400mm long depending on the bike size). Its smaller 27.2mm diameter provides your seat with natural flexibility, 30% more than a standard saddle.
V-BRAKES WITH PADS
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.
27.5" WHEELS & TYRES FOR DRY TERRAIN
The wheels of the ST 100 are tolerant and robust, with 27.5" double-walled 28-spoke rims (26" for the XS size). Start overcoming obstacles fearlessly, including small rocks, cracks, holes and bumps!
Because you're getting started with MTB touring on dry ground, this mountain bike is equipped with DRY 27.5 x 2.0 tyres. Great performance thanks to a central section with low rolling resistance and side knobs that provide good grip on turns.
Platform pedals
The Rockrider ST 100 mountain bike is supplied with hard resin platform mountain bike pedals for added lightness and safety.
If your foot slides on the pedal, there's less risk of injury.
TRANSPORT & STORAGE
We added a quick release system for easily attaching/removing the front wheel.
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 rear wheel.
Tip: a bike rack is an easy way to transport your mountain bike without dirtying your car.
Accessories
Your ST 100 mountain bike comes with a derailleur guard, chainring guard (to keep 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 bag
- Rear pannier rack
- Child seat (depending on the model)
...
COMFORT & SAFETY
Your bike's fittings (chain, derailleur, brakes, etc.) will adjust over time. Take advantage of a free servicing within 6 months after purchase. Our technicians will carry out a 13-point check of your bike. Just come to your nearest Decathlon workshop with your Decathlon card and/or receipt.
LEGAL DISCLAIMER
To ensure components last longer, we recommend a maximum load of 120 kg (rider and MTB included).
COMPOSITION
composition
Bike frame: 100.0% Aluminium
Tips for storage and maintenance
Storage tips
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.
Restrictions on use
Not suitable for XC, All Mountain, Enduro and BMX.
TESTS AND WARRANTY
Test product
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.
Parts guarantee
Lifetime (frame, stem, handlebar). Availability of spare parts: 2 years.