PW-X2

Yamaha's 2020-era flagship eMTB mid-drive: an 80Nm, 250W-rated unit that traded the previous PW-X's narrow punch for a notably wider power band, holding assist all the way to a class-leading 170rpm cadence. Discontinued in favour of the PW-X3, but still common on the second-hand Haibike, Giant and R Raymon market.

Builds early, holds a broad plateau and crucially keeps pulling at high cadence where the original PW-X dropped away. In MTB and Extra Power modes assist runs all the way to 170rpm (155rpm in the lower three modes), only tapering in the final stretch.

The verdict

Yamaha PW-X2 was the motor that finally gave Yamaha a credible eMTB answer to Bosch and Shimano. It keeps the 250W nominal rating and tops out at 80Nm in its two strongest modes (MTB and Extra Power), dropping to 70Nm in the three lower levels, but the real story is the spread: Yamaha widened the assist band so the unit keeps pulling at the high cadences where the old PW-X fell flat. Where the lower modes hold support to 155rpm, MTB and Extra Power keep assisting all the way to 170rpm — a genuinely class-leading cadence ceiling — and Yamaha claims up to 50% more power at 100rpm than its predecessor. On the trail that means you can spin a gear higher and still get a shove.

The delivery is direct to a fault. A Quad Sensor System (incline, speed, cadence, pedal torque) feeds an eager response that reacts the instant you load a pedal, so much so that bikes fitted with it tend to lurch off the mark and can "tremble" if you rest a foot on the cranks at a standstill. Riders chasing the last word in finesse on tricky, low-speed climbs still rate Bosch, Brose and Shimano a notch higher for sensitivity. What the PW-X2 banks in return is reach and refinement of noise: testers consistently praise how quiet it stays even on full power, and the efficient 36V system pairs well with Yamaha's 400/500/600Wh InTube packs for genuinely long range.

It is an older design now, and it shows: more freewheel drag at coast and an audibly more mechanical whirr under load than the PW-X3 that replaced it in 2022. Yamaha publishes its modes by name (ECO, STD, HIGH, MTB and Extra Power) rather than as support ratios — the widely-quoted 360% figure belongs to Giant's SyncDrive Pro, the Giant-tuned version of this same hardware, not to the stock Yamaha unit. No independent lab has published a measured dyno trace for the PW-X2 either, so the power figures here are Yamaha's own claims and a representative curve shaped to its wide-cadence character, not laboratory data. As a used buy it remains a sensible, durable choice; as a new motor it has simply been overtaken.

“It reacts the instant you load a pedal, sometimes before you meant to.”

Character

Rider input

Yamaha does not publish a stock support ratio for the PW-X2; it sells the motor by named modes — ECO, STD, HIGH, plus the MTB and Extra Power modes that unlock the full 80Nm and the 170rpm cadence ceiling. The often-quoted 360% figure is Giant's SyncDrive Pro number, a Giant-tuned version of the same hardware, not the stock Yamaha unit. In all modes it wants very little rider torque before it gives strong assist — hence its trigger-happy reputation.

On the trail

Direct, eager and high-revving — happy to be spun fast and rewards an aggressive cadence right up to 170rpm, but the instant-on response can feel snatchy at walking pace and lacks the low-speed finesse of Bosch or Brose.

Noise

Praised in tests for staying pleasantly quiet even at full assist, quieter than the Bosch Performance CX and Shimano EP8 of its day. No published dBA figure exists for the PW-X2, but it is the one trait reviewers single out; only under hard load does it produce a more mechanical whirr, and even then it is louder than its own PW-X3 successor.

Efficiency

The efficient 36V system pairs well with Yamaha's larger InTube batteries (offered in 400, 500 and 600Wh capacities) to deliver consistently strong real-world range, one of its standout traits in comparison tests.

The case for and against

Strengths

80Nm and a genuinely wide power band that holds assist to 170rpm
Very quiet even at full assist — quieter than Bosch CX/Shimano EP8 of its era
Efficient 36V system, excellent real-world range with 400/500/600Wh InTube packs
Direct, instant response
Durable, well-supported used-market unit

Compromises

Snatchy off the line; can "tremble" at a standstill
Less low-speed climbing finesse than Bosch/Brose/Shimano
More freewheel drag and louder than the PW-X3 that replaced it
Discontinued (2018–2022 era); no independent dyno data exists

How it stacks up

Against the Bosch Performance CX and Shimano EP8 of its day, the PW-X2 matches torque on paper (80Nm) and beats both for quietness and high-cadence reach — its 170rpm support ceiling is well clear of the ~120rpm where most rivals taper — but it trails them for fine low-speed climbing control and natural feel. It is quieter than its own PW-X3 successor yet down on outright smoothness, coast-drag and modern thermal headroom.

OWNER INTELLIGENCE

Most owners report no problems · 4,536 posts from 668 members analysed.

66Bearings and water: the repairer's verdict on the PW-X generation · typical onset: Bearing complaints from ~2,000-7,000 km; water deaths are seasonal (after…

29Speed-sensor and wiring faults misdiagnosed as motor failures · typical onset: Any time; often after assembly or wheel/rotor work.

24Noise: high-cadence squeal, clicking, knocking (common but not normal) · typical onset: From new to ~650 miles; mostly stable rather than progressive.

✓18,953 miles on a 2016 Haibike Full FatSix's original, never-opened Yamaha PW motor - original everything except consumables

Read the full owner report →

Sources: Velomotion — Yamaha 2020 PW-X2 launch & ride impressions · Yamaha Motor — e-bike systems (PW-series) · Yamaha Bicycles — PW-X2 drive technology (modes, 170rpm cadence) · greatebike.eu — Yamaha PW-X2 drive unit (specs: 80Nm, 250W, 36V, 3.1kg).

Bikes running this motor · 2