When it comes to tires, e-bikes put a larger load on tires. The bikes are heavier, and they may see more sustained high speeds compared to bikes without assist, particularly on commuter and mountain bikes. So, tires need to be tougher and more durable. But we wanted to know how are e-bike tires are different from regular bicycle tires, exactly? So we turned to two of the world’s largest bicycle tire 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 tires and e-bike tires?
KENDA: When talking about tires for e-bikes the first thing that needs to be addressed is that for tire 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 tires for these bikes are not required to have any special modifications or certification. For Kenda, we require 25kph e-bike tires to be a minimum of 30tpi casing and we test these tires to internal standards which include speeds up to 40kph (24.85mph) with weights applied to the tire in excess of that expected for bike and rider combinations.
The second category are for bikes that fit into the 50kph speed rating. Commonly referred to as Speed Pedelecs, these bikes will continue to assist the rider at speeds in excess of 25kph. Kenda has chosen to focus on this category along with e-mountain bikes. EMC, Electric – Mountain Casing, is a tire construction that which is optimized for the weight and forces that are applied to e-mountain bikes. Tires with our EMC construction are built to withstand the higher loads on the tire because of the heavier bike and the higher speeds and torque at the rear tire.
MAXXIS: The primary considerations when developing a tire for e-bike use are the increased load bearing capacity, and increased durability in general when dealing with greater load, tread wear, increased torque, etc. This generally also means a slightly higher operating pressure, so beefing up the casing to accommodate that as well. In Europe, e-bike tires must comply with ECE-R75 standards to receive certification. In most of our tires, this is achieved by adding our Silk Shield bead-to-bead puncture protection layer to the casing and by sticking to a single, more durable compound.
BIKERUMOR: Why are they different?
MAXXIS: As mentioned above, e-bike tires are subjected to different abuses than a regular tire generally is, so we design these tires to overcome those unique challenges. Increased weight, torque, and tread wear are all considered.
KENDA: EMC tires are different from traditional tires because of the endurance certification tests that they need to pass. Everything about the construction of the tire has been optimized so that it is the best possible construction for an e-mtb rider. This can include sidewall inserts to strengthen the casing, puncture breakers under the tread surface for enhanced durability, and specially modified tread extrusions or compounds for longer wear life. Further optimization includes making the tires tubeless compatible through the use of tubeless beads and specialized chafer tape at the bead/rim interface.
BIKERUMOR: Are there regulations governing e-bike tire construction and features? If so, what are they and why are they regulated differently?
MAXXIS: The United Nations Economic Commission for Europe has established regulations and test methods that govern tires for mopeds in order to create a standard for safety. Due to the increased load, torque, and speed of e-bikes, they are classified as mopeds for this specific safety standard. These standards can be accessed online (PDF link).
Editor’s note: Those regulations define a moped as “any two-wheeled or three-wheeled vehicle which is fitted with an internal combustion engine having a cylinder capacity not exceeding 50 cm3 and a maximum design speed not exceeding 50 km per hour (31mph).”
KENDA: Currently, the US has no specific regulations that govern the tires on e-bikes. There are limits to speed (32k/20mph), wattage, and dependent on local laws whether or not an e-bike can be used on bike paths or mountain bike trails. In Europe there is the ECE-75R endurance testing. This test is a more rigorous version of the endurance testing that is required for all bicycle tires that are destined for sales in Europe.
The reason for the different certification is because of the need for to handle the greater loads of the bike and the higher torque and speed.
BIKERUMOR: Anything else unique about your e-bike tires compared to your regular bicycle tires?
MAXXIS: As well as the above-mentioned extra reinforcements, our e-bike tires display a standard metric motorcycle tire size designation. For example, the 700x47c ReVolt displays 47/95 – 622 M/C which denotes 47mm wide, 95% aspect ratio (cross-section height is 95% of the width), 622 rim, and motor driven cycle only.
KENDA: Kenda is committed to producing the best quality bicycle tires for traditional and e-bikes. As such, every tire is designed specifically for the application intended by the bike manufacturer and the end user. What this means is that one e-mtb tire may have a construction that differs from another e-mtb tire based on the usage the tire is intended for, i.e. XC versus Enduro.
THE TAKEAWAY: Next time you need to replace or upgrade your e-bike’s tires, be sure to get one with the proper certification. Doing so ensures the tire’s able to handle the extra weight and torque and won’t blow out on your commute or on the trail.