The lightweight Dimension 27.5 is designed to be the ultimate mix of ability and value for young adult riders — and it delivers on every front! Suitable for riders aged 11 and upwards up to 162cm tall, the lightweight Dimension 27.5 bridges the gap between kids bike and full adult bike with style, confidence and a whole lot of fun.

Packed with many of the easy-ride features and fit details from our smaller bikes, the Dimension 27.5 takes things up a notch with full-size 27.5″ wheels and a wide-ratio Shimano Essa 8-speed gear system — because this really is a small adult's bike rather than a children's bike. Tackle every hill, track and back lane with ease, knowing the right gear is always just a click away.

Easy-Pedal Cranks — Our pedal cranks are ergonomically correct, proportional to the child's leg length. They also place the pedals closer to the bike's centre so that children can pedal as smoothly and naturally as possible.

Smaller Grips — Our handlebars and grips are narrower diameter so they fit small hands better, for confidence and control as well as better ability to reach the brakes safely.

Faster Tyres — Special edition Nutrak Speedsters with puncture resistance and reflective sidewalls roll comfortably and smoothly.

Lowered Frames — Our frames are lower where it counts, making it easier to get on and off and increasing clearance for greater confidence.

Steering Limiter — To help prevent falls when learning to co-ordinate pedalling and cornering, the steering has a limit stop that helps avoid an over-steering situation.

Specification

Age Range: 11 years upwards

Height Range: 144cm to 162cm

Inside Leg Range: 69cm to 77cm

Frame: Butted 6061-T6 heat-treated aluminium

Fork: 6061-T6 heat-treated aluminium

Handlebars: 19.0mm OD grip area, 640mm W, 40mm rise, 10° sweep

Grips: 19.0mm ID Velo grips, locking collar, Kraton rubber

Stem: 40mm extension, 10° rise, 25.4mm clamp

Saddle: Madison, soft PU foam padding, 258L x 137W

Seat Post: 27.2 x 350mm, all aluminium

Headset: Upper: ZS44/28.6 | Lower: ZS44/30

Tyres: Nutrak by Vee - Speedster 27.5" x 1.95", reflective strip and flat-resistant belt, natural colour sidewall

Rims: Aluminium, double wall, machined sidewall with wear indicators, 32H F+R, Car-type valve

Front Hub: Aluminium, M6 bolted axle

Rear Hub: Shimano FH-N300 freehub, nutted axle

Shifters: Shimano SL-M315 trigger shifter, Jagwire LEX-SL lubricated cable housing

Rear Mech: Shimano Essa RD-U2000-8 SG w/ protective bash guard

Cassette: Shimano CS-HG400 cassette, 8 speed, 11-45T wide range

Chain: KMC, silver/grey finish

Cranks: Forged aluminium, low Q-factor design, 140mm length

Chainring: 36T, aluminium, double chain retention discs

Bottom Bracket: Thun Germany, sealed bearings, CrMo 119mm axle

Pedals: Nylon resin compact pedals, ball-bearings

Brake Levers: Promax BL367-AL, reach adjustable, aluminium body

Brakes: Aluminium V-brake, adjustable linear spring, Jagwire LEX-SL lubricated cable housing

27.5''

Ridgeback Dimension 27.5 - 2026