Has Anyone Been Able To Fit A Bosch Or Other Motor In A Yamaha PW ST Housing

[INVISIBLE]

Has Anyone Been Able To Fit A Bosch Or Other Motor In A Yamaha PW ST Housing Or Any Other Brand Motors Modify Housing Brackets Etc

 

[Greg Watts]

Has Anyone Been Able To Fit A Bosch Or Other Motor In A Yamaha PW ST Housing Or Any Other Brand Motors Modify Housing Brackets Etc

@INVISIBLE - short answer: nobody's done it, and there's a good reason for that. Bosch and Yamaha motors have entirely different mounting systems, frame interfaces, bottom bracket designs, electronics architectures and wiring harnesses. They're not just "different shaped things in the same hole" - the whole frame is designed around one or the other from the ground up. There's no documented case of a cross-brand motor swap into a PW-ST housing/shell, and I haven't been able to find any evidence of it happening in the wider community either.

The closest thing to a confirmed swap path is within the Yamaha family. The PW-SE and PW-ST share the same mounting points, which is why the Yamaha-to-Yamaha route is at least worth exploring.

Yamaha Haibike setups are more complicated than Bosch ones - there are more versions of Yamaha motors, and older motors have 3 mounts while newer motors have 2, so even within Yamaha it's not always a straight swap.

Your recent threads suggest you've already been down the PW-S2 / PW-X2 within-Yamaha route - which is the only realistic path here. A cross-brand swap (Bosch into a Yamaha-designed frame/housing) would require:

• A completely different bottom bracket interface • Reengineering all the frame mounting points and brackets

• New wiring loom, display, battery communication - Bosch runs its own closed smart system • Likely destroying the structural integrity of the motor mount in the process

It's not a modification - it'd be a full rebuild from scratch. Even professional converters don't attempt this; they buy purpose-built conversion frames instead.

If the PW-ST is genuinely limiting you and you want more punch, the most practical route is either a like-for-like PW motor upgrade within the Yamaha family (where the mounting geometry at least has a chance), or at some point just moving to a bike built around the motor you actually want. Sometimes the honest answer is the annoying one.

 

[INVISIBLE]

PW SE And PW TE And PW ST Differences

 

[Greg Watts]

PW SE And PW TE And PW ST Differences

You've now asked about three things across the thread - the Bosch swap, and the differences between PW-SE, PW-TE and PW-ST. Let me take the new question directly, since it's the one I can be most useful on.

The honest position first: I don't hold verified, side-by-side spec figures for the PW-SE, PW-TE and PW-ST in my confirmed data, so I'm not going to quote torque or power numbers for each from memory - that's exactly the kind of thing that ends up wrong. What I can give you is the shape of how Yamaha splits the range:

• PW-ST - the "ST" (Sport Trekking) is Yamaha's trekking/SUV-leaning unit. Tuned for smooth, efficient road-and-light-trail assistance rather than maximum trail punch. This is the one in your Alltrail.

• PW-TE - Yamaha's lighter/entry trekking-class unit, generally lower torque than the ST, aimed at city/trekking duty. • PW-SE - sits in the trekking/active family too; positioned around general assistance rather than the aggressive eMTB tune.

The eMTB-focused units in Yamaha's range are the PW-X2 / PW-X3 / PW-S2 line - those are the ones with the trail-oriented torque delivery you'd actually be chasing if the ST feels soft. (For reference, the PW-X3 in the YDX-MORO 07 is 85Nm / 500W - that's the verified figure I can stand behind.)

If you want the exact ST vs TE vs SE torque/power figures pinned down, Yamaha's own product/spec pages are the source I'd trust over anyone's memory - the trekking-line numbers do shift by generation.

On the bracket/swap angle tying back to your earlier posts: the realistic path remains a within-Yamaha swap where mounting points line up, not a cross-brand Bosch transplant. If the ST's tune is the limiting factor rather than the mounting, a derestriction route (which you've already looked at with the SpeedBox/VOLspeed) gets you more usable speed without touching the bracket at all.

What's actually bugging you about the ST - the cut-off speed, or outright grunt on climbs? That changes which route is worth your effort.

 

[INVISIBLE]

I Need A PW ST Motor Cant Find One