Manufacturers demand transparent test criteria
Dirk Zedler, head of the renowned, identically named test institute, laughs when hearing that. Details about the set-up of the tests is something he has been waiting for years, says Zedler. In 2010 during the panel discussion at the Vivelo-Conference the Stiwa test manager Holger Brackemann had promised to make them available to him. He hasn't received them to date.
Therefore, according to Zedler, the challenge for the test institutes is to develop a suitable test procedure. For this purpose the data obtained during the test must be interpreted properly and transferred accordingly.
For this reason the bicycle expert posed the crucial questions: How do the testers weigh the different factors they have determined on the road? What do they leave off? How do they transmit the values to the test stand and thus to the bicycle? How do they arrange the test cylinders, how and where do they mount the cycle or the components? "The bicycles must be mounted realistically", he says. Because the test stand is designed to simulate the complete life of a bicycle within a very short time. Too high loads or inappropriate fixings have fatal consequences.
"Therefore you always need an approved frame model as blank sample", claims Zedler. That’s what is called benchmarking in specialized jargon. This means that an institute tests selected requirements on an approved model. It’s only in direct comparison that you obtain a reliable result, says Zedler.
Wrong method – or not?
Apart from test procedures and test set-ups there is no doubt for the expert: "The e-bike standard is weak, it is not yet fully developed." Due to the participation of all EU-countries, it takes a long time to implement fast improvements. For this reason he speaks for a local standard with transparency as ultimate objective. To help the manufacturers to improve their product and the buyers to obtain safe pedelecs.
Author: Andrea Reidl