Yamaha Diversion XJ400S: An Air-Cooled Four That Aimed to End the Era of Judging Bikes by Spec Sheets

It's such a classic-bike thing where the concepts that didn't land end up getting appreciated later — a bike I'd love to see with today's eyes.

First time hearing the name Diversion — I feel like I've also heard it was popular overseas in a different displacement.

It was probably an air-cooled four in a different direction from air-cooled bikes like the XJR400.

An air-cooled four with this kind of philosophy — I'm curious what specifically set it apart from other manufacturers' nakeds at the time.

Aiming for touring-oriented usability and missing the naked-bike boom — it's a shame how the concept and the market just didn't line up.

'Putting an end to the era of judging bikes by spec sheets' — that catchphrase must have been a pretty bold statement for its time.