Your tires on your e-bike are an integral part of your electric bike equation. The tires are the part of the e-bike that connect you to the ground. They provide traction and suspension, and affect the way the bike feels and handles.
First regarding tire diameter…the reason most pedal bicycles have 26 inch wheels is to increase the gearing of the bike. Other than gearing, the taller tires do not make a big difference on ride quality, stability or ride efficiency.
Also for an e-bike the tire diameter effects the gearing. A 20 inch wheeled bike is going to be lower greared than a 26 inch wheel bike. So the 20 inch bike will be a more effective hill climber, and the 26 inch wheeled bike will have a higher speed. The smaller the wheel diameter the more maneuverable and the more storable your e-bike is. Electricbike.com recommends smaller diameter wheeled bikes in general. 20” wheeled bikes (ie bmx) is our favorite.

fat apple 20″ tires, schlumpf speed drive, geared hub motor = dream e-bike
Consider the following when running an e-bike:
1. e-bikes are much heavier than a regular bike (plan for an extra 50lbs)
2. Hub motors appreciate cushy tires to make their ride less jarring.
3. Ebikes are faster than regular bikes.
4. Hub motor bikes are harder to change the tire on than on a regular bike and can leave you stranded.
5. In general you will ride a lot more miles on an e-bike than a regular bike.
Based on the list above, the considerations for choosing an electric bike tire are completely different than for a regular pedal bike.
Also flat tires are a bigger problem than on a regular bike. Read our article here on how to avoid flat tires.
So what we recommend is a substantial tire, as wide as possible with a high load rating. We recommend a width of 2 inches or wider, as wide as your frame can handle. Also you want your tire to be as puncture resistant as possible, since punctures on an e-bike are more likely, more dangerous, and more inconvenient. Hub motors have to be unscrewed and the wires disconnected from the controller (many many wires) to repair a simple flat…so what once was a 15 minute job can turn into more than an hour job or even 2 hours depending on your skill level. Also carrying tools to do this job and actually doing this job while on the road is a very inconvenient proposition indeed.
Also you want your tires to be act as a shock absorber for the hub motor..so the more balloony the better….well maybe not too balloony 🙂
Consider tread patterns that are fairly flat for street and hard packed trail riding unless you are doing hard core off road riding. It is a very rare type of e-bike rider who needs knobby’s. Hard core knobby tires will severely effect the range you get, your ride quality, and even your top speed.
TIres is something you should not skimp on with an e-bike, especially a faster e-bike. You’re subjecting your tires to more stress than you would a regular bike. Also dont forget rim tape and high quality puncture resistant tubes.
Here are some tires recommended by the editors at electric bike.com. Schwalbe tires are best but fairly expensive (up to $60 a tire) but are our favorite tires and get our highest recommendation. if you would like to save money consider the Maxxis tires. Remember, some e-bikes can hit speeds of over 40mph. If this is the case with your e-bike, definately buy the nicest, highest quality of tire you can afford.

schwalbe energizer
The Schwalbe Energizer was made specifically for electric bikes and just came out at this writing. It has a descent interent price of $35 a tire. Notice that the thread is almost smooth.

schwalbe fat apple
The schwalbe Fat Apple is one of the most popular tires for e-bikers. It is big, wide and has a nice efficient tread for on road and light off road use. Excellent price of $35 a tire.

Schwalbe Marathon Plus
The Schwalbe Marathon Plus is a wire beaded tire that markets as being more puncture resistant than a normal tire b using a special layer Schwalbe calls a “smart guard”. This is a efficient tire with descent tread. Great for on road and light off-road use. It is the tire used on the optibike. $45 a tire.

Schwalbe Marathon
Schwalbe Marathon tires are a classic. Same as the marathon plus but different tread pattern and a cheaper $35

Schwalbe Crazy Bob
The Crazy Bob tire is a balloon tire with a wrap around tread which has a fun look. The $35 dollar tire is used on the $12,000 Stealth Bomber (as an upgraded tire). Great for both on-road and off-road riding.

Maxxis Holy Roller
The Maxxis Holy Roller is a really nice off versatile tire with a unique design that rolls extremely well on pavement and still hooks up in hardpack conditions. $30 on the internet

Maxxis Hook Worm
The maxxis hookworm is the ultimate street tire that heats up and grips like a drag tire. Good for jumping as well. $30.