Yamaha YZ125 2024 — Specifications

What, at its core, is the legacy of a legend? For the Yamaha YZ125, the answer is simple: an obsession with pure performance that has been passed down since 1974, without ever faltering. In 2024, as two-strokes become a rarity, Yamaha persists and signs with a machine that has little to do with its ancestors, except for the spirit. At nearly €8400, it doesn’t target beginners looking for sensations, but rather the young rider aiming for the starting grid of a race. It is a competition tool, period.

The major revolution arrived in 2022, with a completely redesigned engine. The 125 cc single-cylinder now produces 42 horsepower, a figure that makes it, according to many, the most powerful 125cc motocross bike ever produced by the Japanese manufacturer. This power is not just a number on paper. It is felt in the way the engine breathes, thanks to a redesigned air intake to reduce resistance by 15%, and a 38.1 mm Keihin PWK carburetor assisted by a Power Jet. The YPVS system has been recalibrated, the exhaust shortened, everything has been optimized for explosive response. Compared to a KTM 125 SX, it offers perhaps a more linear character, but terribly effective, with a controlled over-rev that allows you to hold the revs without panicking in fast, long curves.

This mechanical fury is wrapped in a chassis that has also undergone a slimming cure. The refined tank and radiators reduce the width between the knees by 36 mm, a colossal difference once on the track. You literally merge with the machine. The aluminum twin-spar frame, slightly reworked at the rear, offers a rigid and precise base. The KYB suspensions, already benchmarks, see their low-speed setting improved for even more grip. The front brake, with its new two-piston caliper and 270 mm disc, inspires absolute confidence for last-minute stops. With a seat height of 98 cm and contained dry weight, it remains a physically demanding motorcycle, but with the agility of a funambulist.

So, who is it for? Clearly for the motocross rider looking for the best weapon in the 125 2T category, ready to assume the meticulous maintenance required by such mechanics. It is not homologated for road use, its universe is the circuit. For those tempted by an adventure with an older model, beware. The value of a Yamaha YZ125 from 1993 can vary considerably, and finding parts for a 1982 is sometimes like a treasure hunt on specialized sites like CMSNL. The current version, on the other hand, is a mature, refined product that even celebrates its history with a retro-colored 50th-anniversary edition. It is a concentrate of technology that justifies its price, provided you have the talent and courage to awaken it. Because beyond the numbers, it requires total commitment. It is not automatic, it is demanding, and that is precisely where its interest lies.