There's a good interview online with Kenda and Maxxis via E-BikeRumour. Electric bikes do put a larger load on tyres, although UK speed limits mean that an electric bike doesn't have to have specific e-bike tyres, but some manufacturers do use them anyway. E-BikeRumour asked two of the world’s largest bicycle tyre manufacturers for answers. Here are the replies from Matt Clark, Maxxis Marketing Manager, and Ben Anderson, Kenda’s Road & Cyclocross Marketing Manager
BIKERUMOR: What are the key differences between regular bicycle tyres and e-bike tyres?
KENDA: When talking about tyres for e-bikes the first thing that needs to be addressed is that for tyre manufacturers, e-bikes fall into one of two different categories. The first category is for e-bikes with a speed rating of 25kph (15.5mph); meaning the e-bike motor will stop assisting the rider once the bikes has reached 25kph. The tyres for these bikes are not required to have any special modifications or certification. For Kenda, we require 25kph e-bike tyres to be a minimum of 30tpi casing and we test these tyres to internal standards which include speeds up to 40kph (24.85mph) with weights applied to the tyre in excess of that expected for bike and rider combinations.
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