B'TWIN Rockrider 8.1 Mountain Bike - GreyB'TWIN
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Please select a size
Price in store £0.00 £499.99 **
** From To
From and limited stock
* Sales price at
From and limited stock
* Sales price at
Important: When you purchase a bike online, pedals are not fitted and the stem/bars are not adjusted. Please visit this video to see how to correctly set up your bike.
Life Time Warranty: B'TWIN makes the life time warranty for the frames, brackets, stems and rigid forks. Guaranteeing your Bike for life!
Lifetime warrantyDouble-thickness 6061 T6 aluminium; racing geometry; 12.85kg in size M.
- 2Low weight / lightweightDouble-thickness 6061 T6 aluminium; racing geometry; 1.850 kg in size M.
- 3Accuracy / precisionSRAM X7/X5 27-speed drive train, Shimano Deore chainset.
- 4CushioningRock Shox Recon 100 mm hydraulic fork, handlebar lockout and bounce adjustment.
- 5Brake controlTEKTRO AURIGA COMP 160 mm hydraulic disc brakes
- 6Anatomic designSizes: S (155-165 cm) M (165-175 cm) L (175-185 cm) XL (185-200 cm)
Guarantee : Lifetime warranty for the frame, stem, handlebar and seat post on this bike. Details on btwin.com.
Love the bike, not so sure about the factory setup
Great bike for the price
Setup incorrectly, missing tools
James (United Kingdom)
20-29 years old Man
used for 2 to 8 weeks
I ordered my RockRider 8.1 online after being recommended it on a bike forum I read regularly. I received it a little over a week ago and have put around 100 miles on it so far, and I must admit I'm really enjoying it. It's comfortable, it handles well and feels plenty durable on the trails thanks to the Michelin Country Trail tyres fitted.
However, I was a bit disappointed upon receiving the bike. The handle bars were fitted upside down, and the rear tyre had been put on in reverse. To add to this, I did not receive a user manual as the quick setup guide hinted at, or a spanner for the pedals. Thankfully I had the tools required and so could remedy these issues easily.
All in all, the bike is great, and would recommend it to anyone new to mountain biking. I'm hoping the service I experienced was a one off, as the bike wasn't really usable in the state it arrived.
Rock Rider 8.1
Fanatstic bike it takes what you throw at it
Nothing worth mentioning
Peter (United Kingdom)
50-59 years old
used for More than 2 years I have owned this model since 2010 its still as as good the as the day I bought it . I have covered many miles on and off road and when the time comes I would buy another
Response of the brand
Thank you very much for taking the time to post a review of the b'Twin Rockrider 8.1 Mountain bike. It is a great quality bike with an excellent hard-tail frame. One of our best sellers.
So pleased to read that you've been enjoying it since 2010. Long may it continue.
Peter Lazarus UK Market Manager DECATHLON
Peter found this review helpful
the whole package for the price
craig (United Kingdom)
30-39 years old Man
used for More than 1 year I spent a long time researching the rockrider 8.1 and other bikes in this £500 price bracket and every time I came back to the same conclusion the 8.1 beat the rest of the bikes on the market for overall quality level of parts on it copared to all the brand named bikes out their so for me the decision was made take a risk on a store named bike and i was not dissapointed in the slightest it as took every thing ive thrown at it and more i ride to work every day rain snow or shine and i go on trails when i get time and i really enjoy the rides on it.I've had it for 18 months now and it's had a few problems with it but every time I've returned it to store and they've done a good job and replaced any faulty parts promptly under warranty thanks to decathlon it should keep me going for more years to come and I will certainly be looking to purchase another decathlon bike in the future when they bring out a better range of full suspension 29ers out.
B'TWIN Rockrider 8.1 Mountain Bike - Grey
the bike is grate value for money.
the forks broke and seat is hard
benjamin (United Kingdom)
Under 20 years old Man
used for 1 week or less The forks on my 8.1 bike broke as the adjustment cable snapped in store. But thanks to the life time warranty I got a £220 rock shox recon air replacement instead of the £80 standard oil forks that are on the bike . The bike is fantastic now at off road and on rode fun. I love this bike as it so light and good value for money.
Excellent Value For Money
Light ,and responsive
Tyres are very poor
jason (United Kingdom)
I really like this bike and would recommend it to anybody who does trails / singletrack regularly - its is very good value for money and lovely to ride. The only downside was the set up in store had been done wrong and i had to return the bike after a few days but was sorted straight away !
Frame Double-thickness 8 series competition 6061 T6 aluminium frame; racing geometry; 1.85 kg in size M. Lightweight and resistant. Its geometry offers an ideal combination for climbs and descents.
Available in 5 sizes: S; M; L; XL
Fork New Rock Shox RECON Silver TK 100 mm fork Remote Lock-Out on handlebars. Effective rebound adjustment, can be locked in place with a half turn of the lever.
Drive train SRAM X7 front derailleur
SRAM X7 rear derailleur; 9 speeds;
Push pull SRAM X5 levers.
Shimano Deore M590 22x32x44 crankset with
SRAM PG950 11x32 9-speed cassette. Very reliable and efficient drive train, even in extreme conditions.
Brakes TEKTRO AURIGA COMP hydraulic disc brakes with 160 mm rotors. Powerful, progressive in any circumstance
Handlebar Comp 600/ 640mm raised handlebar, oversize diameter for greater durability. The position is higher to provide more control and comfort without affecting performance.
Stem Rockrider Comp stem, oversize diameter, for more durability.
Steering Aheadset headset by VP.
Saddle New Rockrider COMP saddle by Velo
Seatpost Rockrider COMP seat post
Wheels Rockrider Comp 32 hole rims by Rigida Hub JT D041/D142, 2 mm stainless steel spokes Sealed bearings.
Tyres New Michelin country trail tyre
Restricted use :
Not designed for: BMX, Dirt, descent, or free ride.
The b'Twin mountain bike should not be stored outdoors for long periods of time. It should be stored in a cool, dry place, away from corrosive products and salty air.
Regularly lubricate your chain, regularly check your tyre pressure (recommended before every outing) and check (every 3 months) the state of your hoses as well as all of your screw and nut fittings.