Design engineers of the new JetBike improve riding experience and sustainability with lubrication-free iglidur plain bearings

Owning a car is becoming less and less important for many young people in cities. Studies show that the proportion of pedestrians and bicycles is increasing significantly, especially in urban areas. The car as a status symbol is losing its appeal – instead, the focus is shifting to sustainable, flexible and low-maintenance mobility solutions. JetBike GmbH from Braunschweig is embracing this change and presenting a pioneering solution with the JetBike: an innovative combination of e-bike and car. To fulfil the requirements regarding sustainability and ease of maintenance, the company relies on lubrication-free polymer bearings from igus.

Electric scooters, bikes and compact vehicles: there are numerous alternatives to cars on the market to revolutionise transport. Consumers are correspondingly critical when making their choice. What would be the perfect vehicle for the summer? The tip of the scales is often the issue of maintenance. Who feels like cleaning and relubricating numerous bearing points on a daily basis to get to work on time? That’s what the design engineers at JetBike GmbH in Braunschweig had in mind when developing the JetBike: a car-like e-bike with a full fairing that people can use without driving licence, tax or insurance.

Classic metal bearings as a killjoy

The experts suspected that classic metal bearings could cause problems in the mechanics of the vehicle. “In city traffic, there is always the risk of dust and dirt getting stuck in the metal bearings and making smooth and quiet running impossible,” says Enno Hecker, CEO of JetBike GmbH. The constant risk of corrosion and the issue of relubrication are also unpopular topics. “We therefore decided to replace the metal bearings with lubrication-free polymer alternatives from igus – a decision that has paid off.”
 

“igus took us seriously immediately although as a start-up we only required small quantities at first”

Polymer bearings of the iglidur series from igus can be found everywhere in the JetBike. Sleeve bearings made of iglidur G are incorporated in the steering and on swivel fittings in the chassis, for example. The engineers used versions with flanges for seat back adjustment, among other things. igubal® rod ends and spherical bearings allow for complex motion sequences, and are installed in the linkage of chassis components. The flange mounted bearings make it possible to attach bearing points to the frame over a wide area, for example on the bonnet or boot lid. 3D-printed sliding elements made from the SLS material iglidur i3 are also used in the patented tilting system. “The collaboration with igus was very efficient and pleasant as the company took us seriously immediately although as a start-up we only required very small quantities at first,” recalls Hecker. “It was therefore no problem, for example, to realise special bearing sizes and adapt them precisely to our vehicle. This service at eye level significantly accelerated our design process.”

Polymer bearings: no lubrication and a smoother ride

Polymer bearings have a number of advantages. Firstly, they do not require lubrication: microscopically small solid lubricants in the material allow for low-friction dry operation. “The bearings are therefore significantly more resistant to dirt, more fail-safe and completely maintenance-free. That was exactly what was important to us,” says Hecker. In addition, owners do not need any lubricating greases, which are often CO2-intensive to produce. Secondly, the polymer bearings have dampening specifications. This leads to a smoother ride over bumps in the road. Thirdly, the bearings are robust. When subjected to high loads, they undergo elastic deformation instead of getting damaged. This also increases the reliability of the vehicle. Fourthly, the polymer bearings are up to 80% lighter than metal bearings. This weight saving helps increase the range of the electric vehicle. Due to all of these benefits, the investment in polymer bearings, which are also up to 40% more cost-effective than metal ones, pays off very quickly. The start-up is currently developing a near-series prototype of the JetBike.

 
Find out more about the JetBike: https://www.jetbike-mobility.de/

More information about igus plain-bearing technology: https://www.igus.eu/plain-bearing