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While shopping for new tires on my bike, I saw that some dealers had a specific section for e-bike tires, where the various brands production for e-bikes was present.

Why do e-bikes need dedicated tires?

  • @ChrisH: the ones I got a while ago had printed on the package "50 km/h E-Bike ready" – PlasmaHH Sep 7 '17 at 6:31
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    @PlasmaHH so do the ones on my tourer, and my hybrid – Chris H Sep 7 '17 at 7:35
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They don't need them but they are good to have. I have an e-bike that I use as a daily commuter. Here are my thoughts:

  • E-bikes are heavier than regular bikes and put considerably more power out at the rear wheel (my motor has 350 watts, I add maybe 60-80 watts at most) compared to a regular bike which only has 80 watts alone.
  • if you have an ebike with a rear hub motor, that’s a considerable amount of unsprung weight at the rear. It’s much harder to hop curbs and potholes with an ebike so it’s getting whacked much harder
  • E-bikes travel at much higher average speeds than regular commuter bikes. I average 30km/h with peaks of 40km/h which is the electronic assist speed limit. More importantly, I don't make any attempt to conserve inertia as I do with a regular bike, so I stop at all the stop signs and traffic lights. Thus, there's a lot of braking and acceleration that I do that is hard on the bike and its wheels.
  • Finally, the rear tire needs to be sturdy as it is getting more wear and also taking bigger hits on bumps at higher speeds than a standard tire.

All in all, I'm still on the original tire which is a regular tire. I'm on the tail end of its lifetime which has only been about 1/3 that of a regular tire. I will replace it either with a beefy "regular" tire or go with one from an e-bike line. I think the actual difference between the two (beefy regular or touring and a e-bike tire) will in reality be minimal.

Update 2018.7: I ended up replacing my rear tire ahead of schedule due to a sidewalk blowout. I’m not actually sure if it was natural wear or if the bike was shivved by a thief. Replaced with a tire from an ebike tire line.

TL;DR: Ebikes require a strong, hard-wearing, high speed, puncture resistant tire. These are also roughly the same requirements as touring tires so some vendors are labeling their touring tires as "ebike ready."

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    Not sure your argument stacks up. An ebike adds around 10kg to the bike, doubling its weight, but with a 90kg rider, the ebike+rider is only 10% more weight. An elite rider can put out 1500W peak and sustain around 450W for an hour, so the power of an ebike is typically less than the power tires put on pro racing bikes have to handle. – mattnz Sep 6 '17 at 8:34
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    Yes, I'm not a pro rider nor am I riding in a race. When at the gym and working at the same effort level as when I commute, I only put out around 100 watts max, more than that and I start sweating too much. – RoboKaren Sep 6 '17 at 8:37
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    And as for weight, my ebike is roughly 15kg more heavy than an equivalent bike but it's all unsprung weight with a huge mass centered on the rear hub. This has consequences especially when hitting potholes and curbs. Remember that riders are normally considered sprung weight as we use our arms and legs to absorb some of the shock. – RoboKaren Sep 6 '17 at 8:38
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    @mattnz The relevant comparison is tyres for regular Joe street bikes (and I mean "street", not "road") versus e-bikes, not pro racers versus e-bikes. Your regular Joe isn't putting out 250W, let alone 450. Also, the pros use tyres optimized for speed at significant expense to durability. – David Richerby Sep 6 '17 at 9:32
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    An elite rider capable of sustained output of over 400W is going to have his or her tires changed regularly, probably by the team mechanics – Argenti Apparatus Sep 6 '17 at 12:24
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According to Schwalbe at https://www.schwalbe.com/gb/e-bike.html

For standard pedelecs with pedal assistance up to 25 km/h no specific tyres are stipulated by the legislators. But the loads and average speeds of these bicycles are also higher than in the case of normal bicycles. We therefore recommend only certain tyres as “E-Bike Ready 25”. Primarily, these are the tyres of the Marathon and Energizer series as well as the comfort tyres Big Apple and Big Ben.

I call BS on this. 25km/h is not a high speed, nor is the extra weight significant compared to the weight of the rider. Compare this to touring bikes. A touring bike will generally be expected to ride at this speed (less than 16mph) and the luggage will exceed the weight of a motor and battery - but nobody makes touring bike tyres that are made due to the expected "high speed".

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    Basically what they're saying is that their tougher ordinary tyres (e.g. the marathon series of touring tyres) are good for e-bikes. And an e-bike can maintain 25km/h in circumstances where the same rider couldn't on a normal bike, and accelerate to that speed more quickly. Also the consequences of a sudden failure on a 35kg bike doing 25km/h are significant, so you don't want a tyre that spends much of its life worn – Chris H Sep 6 '17 at 16:53
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    All of Schwalbe's touring targeted tires are also rated as "E-Bike Ready" either 25 or 50. So it seems correct that the needs of touring bikes and e-bikes are similar. Yes, it's marketing, but the people buying e-bikes aren't necessarily the tire-nerds that touring cyclists can be, so genuinely not know that a walmart tire is a bad idea. – Jamie A Sep 6 '17 at 21:28
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    @Criggie In Swiss law there are minimum braking accelerations per wheel (among myriad other regulations). For example a tire on the front wheel of an electric assist bike which has the assist function enabled at speeds over 25km/h (but below 45km/h) needs to be good for 3,4m/ss measured as the average starting at the time when the braking lever is first pulled until full stop, with an initial speed of 40km/h, without any skidding or blocking, with an initially cold tire on a horizontal surface, without using the hind brake. I don't know if every tire automatically passes this and other tests. – Nobody Sep 7 '17 at 20:00
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    Another aspect is that the usual "safety/robustness vs. weight" balance which is heavily in favor of weight for good bikes shifts towards safety and robustness for e-bikes because the weight gain is compensated for by the motor. – Peter A. Schneider Sep 8 '17 at 10:00
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    @ChrisH Google "e-bike riders", images, and try to guess what their average sustained speed on a conventional bike could be. You are not representative. – Peter A. Schneider Sep 8 '17 at 21:46
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In brief - "sales and marketing"

Changing tubes/tyres on an ebike can be more awkward, especially on the powered wheel, plus ebikes tend to attract less "mechanical" riders than regular bikes, being a gateway ride.

So an ebike tyre will be a marketing term for higher puncture resistance and lower rolling resistance, and probably in the wider sizes to cope with the extra weight.

They won't be cheap either, because ebikes aren't.

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    I understand your cynicism, but your answer is a bit confusing as it first claims it is essentially smoke and mirrors, and then you make valid points why a more robust tire may be more appropriate. So which is it? I would also suggest that e-bike tires with sturdier construction will have higher, rather than lower, rolling resistance. Rolling resistance is less of an issue in this use case, given that an electric motor provides assistance. – Rider_X Sep 6 '17 at 15:41
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    @Rider_X the term "ebike specific" is a marketting term, that represents certain features that have been available for a long time pre-dating ebikes. Its nothing new in the underlying tech, just retargetted. – Criggie Sep 6 '17 at 19:45
  • The answer by @Qwerky nails it. Craggie is right - its a marketing gimmick. – mattnz Sep 6 '17 at 20:24
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A regular bicycle tire can be just as sturdy and last just as long under more stress by a regular rider. The joke I have heard among cyclists involve a newcomer to a bike race such as RAGBRAI with an electric bike who inevitably falls behind (and is surprised by this) because regular cyclists (not even pros, just people who ride daily and are serious about cycling) can frequently output more watts on a consistent bike than the legal limits of an electric bike, or at least outperform on stretches where the electric has trouble and falls behind.

So, an e-bike may or may not need "dedicated" tires. But... eBikes are not marketed towards people who are interested in putting in a lot of exertion in their ride. Those people don't need electric assist.

While the question does not say what "dedicated" means, there are a couple of possibilities. One is that, being marketed towards people who are more interested in getting from point A to point B economically which a bit of fitness thrown in on the side, it can make sense to sell "niche" or "proprietary" tires which are optimized towards that goal. These tires can be cheaper to make, at the expense of the second point, weight. But the rider can easily tolerate this since the bicycle is motor assisted. Because of this trade-off a heavier tire can also be made tougher to last longer to match the target market of people who don't want to be on the side of the road changing a tire.

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I ride a regular bike (Trek Fx7.2) and an eBike (Giant Quick E+) in casual fashion (ie not superfit or above average). The Giant weighs about 10kg more than the Trek, but since riders vary over 20kg it can't be a weight issue. The Giant is limited to 25km/h assistance which means I very rarely get over 30km/h (Weight/motor/big tyres makes it difficult), whereas I can cruise at 30km/h+ on the Trek (for limited amounts of time on the flats). So it can't be a speed thing either. Based on this I think it's just a marketing gimmick. Tyres are either built for durability (slower, heavier, more puncture resistant, long lasting) or performance (fast, light, easily punctured, limited life). I can't see how an electric motor changes any of that.

  • Why can't it be a weight thing? For any given rider (e.g., you!) rider+Giant will be 10kg heavier than rider+Trek. Sure, a rider who weighs 20kg more than you will put more weight on the Trek's tyres than you would on the Giant's, but that's not a like-for-like comparison. – David Richerby Oct 26 '18 at 11:29
  • It can't be a weight thing because the tyre doesn't know who's going to be riding the bike. Remember these so-called 'e-bike rated' tyres are supposed to have special thing that makes them work better on an eBike. If that is true, what is the special thing? – Happy Harry Nov 4 '18 at 21:18

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