CX4 race to CX5 race

[SJMP]

Can I replace my 2023 Bosch CX 4 race with a new CX5 race?

 

[Greg Watts]

Can I replace my 2023 Bosch CX 4 race with a new CX5 race?

@SJMP - short answer: no, not directly. And this is one of those situations where the devil is comprehensively in the details. Here's the full picture:

The Mounting Problem The Gen 5 CX motor moved from three mounting points to two. A frame designed for the three-point Gen 4 pattern is simply not physically compatible with the two-bolt Gen 5.

Your 2023 Pole Sonni is built around the CX4 Race, so the motor pocket and mounting interface will be Gen 4 spec. A CX5 won't drop in.

The CX5 Race (CX-R) Makes It Even More Complicated The CX Race motor is OEM-only - Bosch won't sell it as an aftermarket upgrade. It's distributed exclusively to selected eBike manufacturers for their race-focused models.

Bosch has since unveiled a new CX-R drive unit replacing the outgoing CX Race Limited Edition anyway. So the direct replacement you're asking about isn't even available over the counter.

What About Fabricating an Adapter? Theoretically possible, but deeply impractical.

There are two distinct problems: fabricating a new bracket to fit the two-bolt Gen 5 into the three-bolt frame mounts, and replacing the electrical components for Gen 5 electronic compatibility.

The biggest challenge is convincing the Bosch system that it's a legal configuration - the anti-tampering controls may simply disable the motor and throw error codes.

What You CAN Do Two sensible options: