Bafang vs Bosch vs Shimano vs Yamaha motors explained

Last checked Oct 29, 2026 · By EbikePost editors

Short answer

Bosch, Shimano and Yamaha are component makers: they sell drive systems to bike brands, and mostly make mid-drives. Bafang makes both mid-drive and hub motors and also supplies bike brands. The torque numbers each maker publishes aren't measured the same way, so we don't rank them. What matters more for you is the motor's job (a light commuter or a steep-hill hauler), the app, and who will service it. Our figures below come from the makers' own pages.

The bike's spec sheet says "Bosch" or "Bafang" or "Shimano STEPS," and you're trying to work out whether that matters. It does, a bit, but mostly for who supports the motor after the warranty and how much of its behavior you can adjust from your phone.

If you're still deciding between a hub and a mid-drive, read hub vs mid-drive motors first. This page is about the four names.

What each maker publishes

Maker	Drive types	Published examples
Bosch	Mid-drive and hub	Performance Line CX: 120 Nm max torque, 750 W max, 6.2 lb. Performance Line SX: 60 Nm, 600 W, about 4.4 lb. Hub Line: 45 Nm, 400 W, about 5.1 lb (motor only)
Shimano	Mid-drive	EP801: Shimano lists 85 Nm; check Shimano's current spec page for your bike's exact unit
Yamaha	Mid-drive	36V PW family: PW-XM and PW-X3 at 85 Nm, PWseries S2 at 75 Nm, PWseries ST at 70 Nm, PWseries C2 at 55 Nm
Bafang	Mid-drive and hub	M820: 80 Nm, 250 W rated, 2.3 kg. M510: 110 Nm. M620: 170 Nm, 1000 W rated. G370 rear hub: 30 Nm, 250 W, 2.0 kg

Don't read this table as a ranking. Bosch gives "max. torque." Bafang's pages use different words for different models: "peak torque," "max torque," and "Boost-to-Limit." Yamaha's PW-X3 page says it delivers 85 Nm "throughout a wide cadence range." Each maker defines its own number, and you can't line them up across brands from a spec sheet.

Bosch

Bosch's US site lists a mid-drive Performance Line CX with a 750 W peak (250 W rated), and says it's controlled through the eBike Flow app. The lighter Performance Line SX is its slimmer drive unit. The Hub Line (BDU306Y) puts the motor in the rear hub, with a published 45 Nm and a 28 mph supported speed. Bosch notes that the values can be lower on delivery and can be changed in the app, and that higher power can mean more wear and less range.

On service, Bosch's US site points to a dealer search and says it gives specialist dealers in-depth training. Its page doesn't state warranty terms, so look at the Bosch help center or your bike brand's warranty. On a Tern, for example, the Bosch motor and battery are third-party parts covered by Bosch's terms, not Tern's (see our brands guide).

Shimano

Shimano's STEPS drive units are mid-drives. The app is E-TUBE PROJECT Cyclist. Shimano says it lets you set up two assist profiles: a basic one with three patterns and a fine-tune one with up to fifteen, and covers firmware updates. Shimano's FAQ adds an important catch: the settings available depend on the factory setting chosen by each bike brand, and some bikes lack the wireless unit needed to connect.

We couldn't read Shimano's product pages directly, so we aren't going to quote more of its numbers here.

Yamaha

Yamaha's global site lists a 36V PW family from the PW-XM and PW-X3 down to the PWseries C2, plus coaster-brake and speed-pedelec variants. The PW-X3 is described as about 10% lighter and 20% smaller than the PW-X2. Yamaha's PW-X3 page doesn't publish a weight or wattage. The site has an app section called "Yamaha Motor On," but we couldn't read what it does.

For US buyers: Bikerumor reported in 2024 that Yamaha's US arm was ending its own e-bike sales. We haven't found a primary Yamaha statement on how US service for drive units works, so ask the bike brand.

Bafang

Bafang's M-series page lists a wide set of mid-drives, from the M215 at 80 Nm and 250 W to the M620 at 170 Nm and the M615 at 160 Nm. Its hub motors are a separate range; the G370 rear motor Bafang lists is 250 W, 36 V and 30 Nm. Bafang's OEM area is where bike brands source parts, so a Bafang motor often arrives inside another brand's bike, and that brand is who you'll deal with for service. We didn't confirm a Bafang rider app from the pages we read.

How to use this

Start with your use. Hills and cargo, a heavy rider or a long climb point to a mid-drive with a high published torque. A flat commute may be fine with less.
Find the exact model. "Bafang" or "Bosch" alone doesn't tell you which unit. Look for the model name (CX, SX, M510, EP801) in the spec sheet.
Ask who services it. For Bosch, look at the dealer search. For motors inside another brand's bike, the bike maker's warranty and support page come first.
Check the app. Settings that you can change from your phone depend on the motor and the brand's configuration.

Stop here: contact the maker or a qualified e-bike shop

If you need torque, wattage or service details for your own bike, ask the bike's maker. Don't open the motor, and don't change speed or power limits.

Common questions

Is Bosch better than Bafang? We don't rank them. They make different drive units for different jobs, and their torque numbers aren't measured the same way.

Is a mid-drive always more powerful than a hub? No. Bosch's Hub Line publishes 45 Nm while Bafang's M820 mid-drive publishes 80 Nm, but Bafang's G370 hub publishes 30 Nm. Compare specific models.

Can I upgrade my motor? That's a question for your bike's maker. Don't swap or modify a motor yourself.

Which brand has the best app? We haven't compared apps. Bosch (eBike Flow) and Shimano (E-TUBE PROJECT Cyclist) both publish what theirs does.

Sources (12)

Last checked Oct 29, 2026