Yamaha YZ125 2017 — Specifications

Can a motocross bike become an icon? For the YZ125, the question doesn’t even arise. Since its inception, this two-stroke has forged its legend on dirt tracks, and the 2017 version we’re examining is just a recent chapter in a story that began decades ago. With 40 horsepower scraping 30 kW for an incredibly light weight of 95 kg fully fueled, it sends a clear message: here, we’re talking about pure power, a killer power-to-weight ratio, and raw sensations. As a comparison, against a KTM 125 SX, it’s close, but the Yamaha often plays the card of progressiveness and track handling, where the Austrian bike can be more nervous.

To understand this machine, you have to accept its philosophy: it’s a competition weapon, period. Its 124 cm3 single-cylinder two-stroke engine, paired with the six-speed gearbox and the famous YPVS system, is a masterpiece of responsiveness. It demands high RPM, engagement, and a good dose of technique to be fully exploited. It’s not a bike for beginners, but rather the perfect tool for a young, ambitious rider who wants to train before potentially moving on to a 250F. Regarding price, you have to face the facts: at its launch, it displayed a price of 7299 euros, a significant investment for a non-homologated machine, reserved for circuit or private land use. Today, if you’re looking for a used model, prices can vary enormously. For an older model, like a 1990 or 1993 in good condition, it’s common to see listings around $2700 on the used market, a price that fluctuates with condition, history, and any potential modifications.

The great strength of this 2017 YZ125 lies in its continuous evolution. That year, Yamaha notably increased the front brake disc to 270 mm, a detail that appeals to demanding riders on late-braking corners. But the essential package already came from the major restyling of 2015. The bike then inherited a streamlined silhouette, aggressive “Speed Block” graphics, and, above all, a redesigned technical base. The 48 mm inverted fork and Monocross shock absorber, derived from the YZ-F four-stroke models, offer complete adjustments and exemplary traction. You’ll also find practical touches like the clutch clearance adjustment knob, borrowed from its bigger sisters, which simplifies life in case of quick adjustments.

So, is the Yamaha YZ125 the most performant 125cc motocross bike ever produced by the Japanese manufacturer? The debate is open against fierce competitors, but its track record and longevity speak for themselves. Lightweight, agile, and equipped with an engine tuned to deliver its power across the entire RPM range, it remains a benchmark. For enthusiasts looking to maintain or restore it, resources such as online parts catalogs, like CMSNL, or the search for specific parts for older models, like a 1982, are essential. Yamaha itself, through its partnership with Italian preparer YRRD, also offers competition kits to push the machine even further. Ultimately, this YZ125 is not a motorcycle, it’s a rite of passage. It demands everything from the rider, but in return, it offers a purity and riding sensations that few modern machines can still match.