A proper junior road bike for young riders ready to get serious.
The Protege Fastrace 451 is built for kids who have outgrown a basic kids’ bike and want the feel, fit and speed of a real road bike. With a lightweight 6061 aluminium frame, carbon fork, 9-speed drivetrain and compact 451 wheels, it is a capable choice for young riders getting into road riding, junior racing, triathlon or trips to the velodrome.
At 8.53 kg, it keeps weight sensible for smaller riders while giving them the confidence of drop handlebars, reliable disc braking and gearing that works for both flatter family rides and hillier routes. It is designed for riders approximately 125–150 cm tall, generally around ages 5–8 depending on confidence, proportions and riding experience.
Built around young riders
This is not simply an adult road bike scaled down. The Fastrace 451 uses a youth-focused cockpit with a short 50 mm stem, compact 38 cm handlebars and 140 mm cranks to help young riders reach the controls comfortably and pedal efficiently. The short-reach setup makes it easier to learn how to ride in the drops without feeling stretched out.
The carbon fork helps reduce weight at the front of the bike and takes some of the sting out of rough chipseal, keeping the steering light and comfortable for smaller hands and arms.
9-speed gearing for real riding
The L-TWOO 9-speed drivetrain uses an 11–32T cassette, giving the Fastrace a useful spread of gears for building speed on the flat and getting up Christchurch hills without turning every climb into a battle. It is simple enough for young riders to learn, while offering a much closer road-bike feel than a single-speed or basic kids’ drivetrain.
Fast 451 wheels and road-focused tyres
The 451 wheel platform is made for speed. Its lightweight aluminium rims and narrow 20 × 1-3/8 tyres roll efficiently on sealed roads, helping young riders carry momentum more easily than they would on wider, slower kids’ tyres. Presta valves also make it straightforward to use a quality floor pump when topping up pressures before a ride or event.
Confident braking
Disc brakes give young riders predictable control in changing conditions, whether they are learning to manage speed on a descent, riding in a group or heading out on damp winter roads. They are also a practical choice for day-to-day use, with consistent braking performance and straightforward workshop servicing.
Key features
- Lightweight 6061 aluminium frame
- Toray T700/T800 carbon fibre fork
- Approximate bike weight: 8.53 kg
- L-TWOO 9-speed drivetrain with 11–32T cassette
- Youth-specific 140 mm cranks
- Compact 38 cm drop handlebars and 50 mm stem
- 451 aluminium wheelset with fast-rolling road tyres
- Disc brakes for dependable control
- Designed for riders approximately 125–150 cm tall
Who is it for?
The Fastrace 451 suits the young rider who is ready to move beyond a flat-bar kids’ bike and wants a genuine road-bike position. It is ideal for family road rides, junior triathlon, entry-level racing, track riding and kids who simply love going fast on smooth paths and sealed roads.
Because children of the same age can vary greatly in height, reach and confidence, we recommend checking fit in store before buying. A bike that feels comfortable and easy to control will always be more enjoyable than one chosen on age alone.
Our thoughts
It is great to see a junior road bike with sensible proportions instead of just smaller wheels fitted to an oversized frame. The Fastrace 451 has the key ingredients we look for: low weight, a carbon fork, compact controls, usable gearing and a position that lets a young rider develop proper road-bike skills. It is a strong option for a child who is genuinely keen to ride further, faster and more often.
Why buy from Chain Reaction?
- Professionally assembled and safety checked by our workshop team
- Help choosing the right size and setting the bike up for your child
- Advice on pedals, helmets, clothing and essential ride gear
- Ongoing local workshop support from a Christchurch bike shop
Specifications
| Frame | 6061 aluminium alloy |
| Fork | Toray T700/T800 carbon fibre |
| Drivetrain | L-TWOO 9-speed |
| Shifters | L-TWOO R5 disc |
| Rear derailleur | L-TWOO RD-R5009-M |
| Cassette | L-TWOO R5, 11–32T, 9-speed |
| Crankset | 140 mm crank length |
| Bottom bracket | Square taper |
| Brakes | Disc brakes |
| Handlebar | 38 cm wide, 31.8 mm clamp |
| Stem | 50 mm, 31.8 mm clamp, -7° rise |
| Wheels | Aluminium alloy rims, 24H, Presta valve |
| Tyres | 20 × 1-3/8, 60 TPI |
| Seatpost | Aluminium, 27.2 × 280 mm |
Specifications are subject to change without notice. Component substitutions may occur where required by manufacturer availability.
