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Btwin Rockrider ST900 Mountain Bike 20" Kids 3'11" to 4'5"
20-inch bike with 6 speeds, front suspension, double disc brake
Free shipping over $49
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.
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
Pleasant aesthetics, good ride, solid, perfect for this age group
Rear wheel: the freewheel bearing is not mounted correctly, which makes it difficult for the wheel to rotate and does not roll straight. Even if it is cheap, the wheel should be freewheeling and of good quality. It should be covered by the warranty. Otherwise, I am satisfied with the bike.
Great product
At first glance this bike is perfect: even for 5 times more expensive there is nothing lighter on the market, and at this age that is decisive. The gears work pretty well and the front brake, although cable, does the job pretty well, it's hard to want better for this price. Two big problems mar this beautiful picture: the fork and the transmission. The fork is just perfectly useless, at this level of non-function you might as well put a rigid one, at least the bike would gain in lightness. At this price I suspect that there is no fork capable of cushioning a featherweight, but creating the illusion of one is not in line with the pragmatism of a Decathlon product. In terms of transmission, everything relies on the crankset protections which prevent derailment. Once this one is broken (which happens quickly since they are made of plastic and very exposed) the bike constantly derails no matter what you do to it. And as the part is not referenced it seems that changing the crankset is the only possibility, but we already know that it will only last a few outings. Too bad, it's nice to see a Decathlon product being on par with other much more (too) expensive offerings.
Only negative comment given the price, there should be a mudguard and a kickstand
Very light and robust bike.
It goes very well
The bike is well made. My son is very happy.
Alright
Very good product
great product but still expensive in my opinion
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.
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 Inch & 24 Inch KIDS BIKE STABILIZERS (Model Code 8550741)
Guarantee
Lifetime (frame, stem, handlebars). Availability of spare parts: 2 years
Origin
Imported
Law label information
Btwin Rockrider ST900 Mountain Bike 20" Kids 3'11" to 4'5"
Your location: City, ST
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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.