You are here

Derbi GPR 50 2004

3690

Make: 

  • Derbi

Model: 

  • GPR 50

Year: 

  • 2004

Transmission type: 

Chain

Cooling system: 

Liquid

Category: 

Sport

Engine type: 

Single cylinder, two-stroke

Front brakes: 

Single disc

Rear brakes: 

Expanding brake (drum brake)

Overall height: 

1,135 mm (44.7 inches)

Overall length: 

1,900 mm (74.8 inches)

Overall width: 

670 mm (26.4 inches)

Displacement: 

49.90 ccm (3.04 cubic inches)

Bore x stroke: 

39.9 x 40.0 mm (1.6 x 1.6 inches)

Fuel system: 

Carburettor

Gearbox: 

6-speed

Color options: 

Red/green/grey, Grey/green

Front suspension: 

Inverted hydraulic fork, 35 mm

Rear suspension: 

Progressive single absorber

Front tyre dimensions: 

90/80-17

Rear tyre dimensions: 

110/80-17

Front brakes diameter: 

260 mm (10.2 inches)

Rear brakes diameter: 

220 mm (8.7 inches)

Wheelbase: 

1,303 mm (51.3 inches)

Fuel capacity: 

7.25 litres (1.92 gallons)

Compression: 

13.0:1

Front suspension travel: 

95 mm (3.7 inches)

Rear suspension travel: 

31 mm (1.2 inches)
Oh my. It’s not often that these hallowed pages have motorcycles eking out little more than 8 bhp, but rules are there for breaking. The fact that there are lawnmowers out there with more horsepower than the Derbi 50cc GPR is beside the point. In fairness, when searching on the google-machine, the interns at Shepster Towers did come across a Honda lawnmower with 189 horsepower, more than a Yamaha R1, which is beyond ridiculous! We then lost said interns down the rabbit-hole of the internet, where they were last seen casting admiring glances in the direction of the British Lawnmower Racing Association. But we digress.

Derbi itself is an amalgamation from the Catalan-phrase Derivats de BIcicletes (derivatives of bicycles), harking back to the days when the business first started out in the streets of Barcelona simply fixing and hiring bicycles. The Derbi 50cc GPR, a Spanish a race-replica bike now part of the massive Piaggio group consisting of Vespa, Aprilla and the like. Indeed, it actually looks fast, which may be scant consolation as you’re maxing out the little Derbi at 55mph based on a fuel tank full of pure-willpower. With throttle restrictions in place, which tells you the target age-demographic for the Derbi, you’re facing down the snail-like barrel of 30mph. According to various forums, they’ve managed to achieve speeds closer to 75mph, presumably downhill in a riotous tempest. If you ever found yourself in a situation where you needed to slow down, and the wind wasn’t already doing that, you’d be pleased that Derbi saw fit to install a front about equal size to that of the front wheel – a 300mm single disc and twin-piston radial caliper.

Kidding aside, the Derbi is actually a proper bike achieving proper road-going speeds, for a fraction of the cost of larger bikes. It has an electric start, single-cylinder two-stroke engine, with a six-speed gearbox fed by a single 17.5mm carburettor. The Derbi has pedigree too, approaching it’s 100th year and having won world championships in the 50cc, 80cc and 125cc classes. In particular, the 1972 50cc Derbi looks exactly what you’d expect from a racing motorbike, but with tyres stolen from a push-bike. Additionally, given the GPR is only a smidge above a 100kg, this little pocket-rocket can be thrown into bends at speed <as much as it can muster anyway!> and would be excellent fun if you could ignore the regularly reported quality problems in the chassis. A mere blip when you’re starting out learning to race your first motorcycle!
 
References

Do You Know This Bike?

Please let us know if you have any more information or images relating to this specific motorcycle or if you believe the information might be incorrect. For any new information or changes please Contact Us.