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Redesign fenders for electric scooter Exo Neutrino


Get your creative hat on, redesign the fenders of an electric scooter called Exo Neutrino, and bag a cool bombproof GoPro Hero camera.

Exo Neutrino (www.exo-bikes.eu) is a tiny electric scooter that handles like a bike, accelerates like a pocket rocket, drives you 40 miles / 60 kms in one go, and fits into the elevator. Designed with the environment in mind it’s the perfect urban companion.

The challenge – redesign the fenders

The challenge is to redesign the current plastic fenders on Exobike (drawings and CAD models below). They’re currently done using the extrusion technique and are too fragile and not the best looking. Your goal is to design and engineer new fenders using ABS plastic that will be manufactured by the common molding method.


  • Fixing points at places shown on the drawings

  • Front fender uses 2 x M10 bolts, back fender uses 4 x M4 bolts

  • Tire clearance of 30 mm

  • Width of the fender must be at least 20 mm greater than the width of the tire

  • Must be easy to manufacture using common molding methods from ABS plastic

  • No shorter / longer than shown on the drawing

  • Design – Neutrino has funky sharp edges and corners, try to match your design to this. But don’t be afraid to try creative approaches.

  • Weight – This is an electric scooter, less weight makes it go and run faster and longer.

  • Functionality – It’s a fender, it should protect the rider from dirt, the occasional puddle, mud and other debris found on the streets.

  • Ease of manufacturing, ease of installation.

Download specification


  • Winning design will be chosen based on the requirements outlined on the right.

  • The competition starts on 8th of July, 2011 and ends on 31st of July (end of day GMT).

  • The competition is open to everyone.

  • Only models uploaded to GrabCAD library participate in the competition.

  • You can submit several designs.

  • You’re free to choose your CAD software as long as you also upload a STEP or IGES file.

  • Tag your model with “exobike” for searchability.

  • You may keep your model private but you need to share access to indrek@grabcad.com

  • Private models will be made public after the competition deadline.

About the jury?

The winning design will be selected by a joint jury of Exo and GrabCAD team and announced here in our blog.

About Exo Bikes

Exo-bikes belong to a new class of urban vehicles: more powerful than any of the current e-bikes, but smaller and more urban-friendly than any of the e-scooter or e-motorcycles.

Exo weighs approximately 65 kg and travels up to 60 km per single charge with max speed of 45 km/h. The vehicle can be used either for fun or for practical purpose.

More info: www.exo-bikes.eu

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