Btwin Rockrider ST900 Mountain Bike 24" Kids 4'5" to 4'11"

Lovely bike great value

Bike gear lever not returning to allow gears to be operated fully despite a pre delivery inspection. Had a two hour round journey to collect the bike and another two hour round trip to return the bike the next day. Gear lever mechanism had to be stripped and freed off to allow operation. I just can't understand how this could have been missed during a pdi especially on a child's bike where safety is paramount.. The bike it's self is really nice and looks great so I would recommend this model.

The bike is fine. The quality of the assembly was rubbish. Rear derailleur not properly set up, necessitating a trip back to the store the next day for it to be resolved. Not informed about the 3-month check either, despite it saying on the form I had been. My confidence that this bike has been properly assembled was therefore pretty low, and to top it off I was accused by the mechanic of having damaged it! Sad to say I am pretty unlikely to buy any more bikes from Decathlon as a result.

Great bike. Was worth paying the little more for a better bike. My son loves it.

My little boy advanced his riding skills so quickly on this bike, it was just perfect for him. He is a tall 7 year old and this was his first bike with gears, they were so easy to use he took to it straight away.

Bought this bike for my 9 year olds birthday. Wanted a lighter weight bike for him. It is extremely well made. It helps that it is checked over by the Decathlon staff which is a bonus. The great thing about this bike is the disc brakes. These will give my son extra confidence when riding.

Great value as always, disc brake and nice quality bike.

Bought for christmas and my son (6yrs) absolutely loves his new bike, top of his christmas presents! Set up by the team at Decathlon Gateshead, it's been stored until Christmas Eve, and he launched himself at it on the big day. Within an hour of being awake, he was outside. First bike with gears, gripshift makes this so easy for him, the size is perfect and he was off zooming up and down the street with ease. The next day, we went out further, confident and riding well, the bike handles the riding. Next, we'll be hitting the trails.

Great bike for the price, sadly I think the chain is too short, will pop in in Jan to sort it.

We where met with very friendly staff and given great service. My grandson will enjoy his Christmas present

Bought as a Christmas present for my son, delivered fast with minimal assembly, it’s a great quality bike. expect to pay twice as much from a high street bike shop ! Spot on Decathlon

First off, I went to pick the bike up. I turned up at the store to find it had already been built. I was not made aware of this as I wanted to build it with my son himself, plus, it would have been much easier to transport and wrap for Christmas. Decathlon, you need to give people the choice. So that aside, it’s not a bad bike. Looks nice, although the frame design is a little dated and the head angle could do with being a bit slacker. It mentions in the advert that it has oversize handlebars. They’re really not oversize at all, they are 2cm wide than my sons current 20 inch wheel bike. This bike could do with around 580mm bars at the minimum. Grips are OK but quite smooth so will be terrible when wet. Tyres are a hard compound, so they’ll likely last a while, but grip wise they’ll not be great. They could also do with being 2.1 wide rather than 1.95 which looks quite skinny on a bike of this size. Brakes are budget, but do a decent enough job of stopping. I don’t see them lasting too long though due to the quality. It shifts quite nicely to be fair, and has actual thumb shifters rather then those horrible twist shifters you see on most kids bike, so it’s a thumbs up for that. This bike would benefit from a smaller chainring though to give more climbing power. Weight? Well, they advertise 12kg, it’s more like 12.5 on the scales I used. Still light though and I’ll lose half a kg just upgrading the heavy tyres. Suspension is where I was most disappointed to begin with. OK, I expect cheap spring forks, but I expect them to actually work. They were very stiff, almost like they were getting stuck on the stanchion covers. I ended up having to service the forks (completely take them apart) and lube the stanchion covers along with all moving parts. Now that has been done they are a lot smoother, but should have been like that in the first place. Upgrade the tyres and bars, service the forks and you’ll be fine.