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Rockrider ST900 Mountain Bike 20" Kids 3'11" to 4'5"
20-inch bike with 6 speeds, front suspension, double disc brake
See shipping rate at checkout
Final Sale: No returns or exchanges
Free returns
Free pickup
San Francisco, 735 Market St. Options
Select an available color and size to see options.
Product Videos
Product Features
Easy to use
6 speeds, quick-release saddle, quick-release front wheel
Bike safety
Double disc brakes provide powerful and easy braking.
Shock absorption
Suspension fork.
Lifetime warranty
B’Twin offers a lifetime warranty on the steel frame, stem, and handlebar.
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Image Gallery
Questions & Answers
Look for product information, frequently asked questions, opinions...
Question:
How much does this bike weigh?
Answer:
This bike weighs aproxamately 21lbs
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Product Customer Reviews
This purchase was made for my grandson's birthday. he was delighted.
I recommend this bike, the boy is very happy with it!
For my still "small" son, an excellent purchase. Adequate value for money
In two years without a single defect.
Very good bike, adopted very quickly by my son. I recommend.
Very good bike, in the light and durable range. Nice look and clearly visible. Easily adjustable.
Grandson happy in every way on his Rock rider mountain bike...
Nice bike. Effective braking, gear changes suitable for children.
Great
Fed up for the moment
My son has not been able to use the bike for 15 months because Decathlon has failed to supply a crankset, let alone a new brake fitting.
Very good solid bike pretty
Good product, somewhat expensive for a children's bike that is more expensive than some for adults. The front brake locks too much, easily blocking the front wheel, which can cause the child to fall.
Price/performance is simply brilliant.
Bike that deteriorates quickly. I had to replace the brake levers and steering bearings after six months. This bike is poor value for money.
Size Guide
Additional Product Information
Composition
Frame (for bike): 100.0% Aluminium
Frame
Aluminum frame designed by B'Twin. The lowered frame geometry makes it easier to get on and off the bike.
Drivetrain
6 speeds. Ultra-soft grip shifter for kids: Change gears using a grip shifter, which is easier and safer (kids don't have to let go of the handlebar to change gears). B'Twin chose this shifter as it is extra soft and specially sized for kids' hands.
Handlebar / stem / steering
Mid-rise stem and handlebar.Quick-release saddle. Comfortable, reinforced (plastic shell) saddle that provides a comfortable position. Fast, tool-free saddle adjustment. B'Twin selected this reinforced saddle for its tried-and-tested durability (should the bike fall over, for instance).
Brakes
Very reliable double disc brakes. B'Twin chose to equip this bike with a double disc Brake system for its ease of use, easy maintenance, and greater braking power.
Warranty
Lifetime warranty on manufacturing defects for all metal frames, rigid forks, stems, and handlebars.5-year warranty on all carbon frames and forks.2-year warranty on all other parts.Excludes damages arising from normal wear and tear, misuse, negligence, and unauthorized modifications.
Compatible accessories
KIDS BIKE STAND 100 (Model Code 2694189)20” & 24” KIDS BIKE STABILIZERS (Model Code 8550741)
Guarantee
Lifetime (frame, stem, handlebars). Availability of spare parts: 2 years
Origin
Imported
Law label information
Rockrider ST900 Mountain Bike 20" Kids 3'11" to 4'5"
Your location: City, ST
Please enter a valid city with state or zipcode. Example: San Francisco, CA or 94101
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Heavy products return policy
If you return a product you will receive a refund for the purchase price plus any applicable sales taxes, less any non-refundable charges.
Decathlon will cover all shipping costs associated with your return except for items excluded from our return policy such as bikes, basketball hoops, snowboards, surfboards, tents, and other larger / heavier items.
Return costs for heavy products:
Weight Thresholds | Shipping within California | Shipping outside of California |
---|---|---|
> 9 lbs | $20.00 | $25.00 |
> 30 lbs | $50.00 | $65.00 |
> 100 lbs | $100.00 | $125.00 |
> 200 lbs | $200.00 | $230.00 |
If you return a product at any of our store locations, we will gladly help you find the best alternative product or refund you on the spot.