Hub Motor Torque: Why 45 Nm Is Not 65

A hub-motor torque number and a mid-drive torque number are not the same measurement. The hub figure is twist at the axle, where the wheel is. The mid-drive figure is twist at the crank, before the chain and the gear you are in. Bosch, as Velomotion quoted it on 15 September 2026, sets the Hub Line’s 45 Nm next to 65 Nm of a mid-drive and treats them as a similar feeling. That is a feel sentence. It is not physics, and it does not make 45 equal 65.

Where the number is taken

A mid-drive sits at the bottom bracket. The torque rating is how hard it turns the chainring. First gear multiplies that. A tall gear divides the force at the tire and adds speed. The same 85 Nm mid-drive is a different shove in a climb gear than it is in a top gear. A hub motor does not get that multiplication. Its torque is already at the wheel. Forty-five newton-meters there can feel stronger than forty-five at a crank in a hard gear, and weaker than forty-five at a crank in an easy gear. “Feels like 65” is one gear, one hill, one marketing sentence. It is not a conversion factor you can reuse.

The Lundi 27 is the example, because two reviews used two different mid-drive numbers in the same week. Velomotion’s Bosch line is 45 beside 65. Cleanrider’s old-bike line is 75 Nm, and then Moustache’s comparison is 65. If a listing averages those into “about 70,” it has invented a motor. The hub versus mid page is where the chain wear goes. This page is only the unit.

Watts are still watts

Torque is not the power cap and it is not the class. The Hub Line’s other printed number, in that Velomotion block, is 400 watts maximum. A U.S. class sticker cares about the rated motor and the speed where assist cuts out, under the three-class rules. A 400-watt maximum on a European card is not a 750-watt U.S. rating, and it is not permission to ignore the cutout. Watts are volts times amps. Newton-meters are not watt-hours. The watt-hour page is the tank. Torque does not tell you how far the tank goes.

If the gear can multiply it, the number was taken before the gear.

How to read the next listing

Ask where the newton-meters are measured. If the ad says “45 Nm, equivalent to 85 Nm mid-drive,” the second number is a slogan unless the maker shows the gear and the test. Write down the maximum watts separately. Write down the watt-hours separately. A hub that is kind to a chain is still a single ratio. A mid-drive that wins on a wall still eats the cassette. Neither sentence is the other one’s torque figure. When two reviews disagree by 10 Nm about which mid-drive the hub is “like,” quote both and buy the hub’s own number.