Inspired by genius
Ever heard the expression ‘Small is beautiful’? It could have been created for the all new YZF-R125, the exciting new member of the R-series family and the most advanced 125 production supersport machine that Yamaha has ever built.
This radical, high-revving, fuel-injected 125 is the work of the same engineers who created our legendary YZF-R1 and YZF-R6 supersport bikes. And, as you’d expect, the YZF-R125 is packed with advanced MotoGP technology as well as a whole range of R-series type engine and chassis features. Its liquid-cooled, 4-stroke, 4-valve, single cylinder, SOHC engine is tuned to deliver free-revving performance right through to maximum power at 9000rpm – and for instant response and efficient operation this remarkable 6-speed 125 is equipped with a compact fuel injection system.
The race-inspired chassis features a Deltabox frame and aluminium swinging arm for outstanding handling performance, and lightweight 5-spoke wheels help to minimise unsprung weight to give impressive road holding. A large diameter 292mm front disc with a 230mm diameter rear disc make for effective stopping power, and the aggressive R-series bodywork lets everybody know exactly where this bike is coming from.
The YZF-R125 is targeted at the discerning buyer who demands best-in-class engine and handling performance as well as winning R-series style. In the engine department, the new R125 benefits from a 4-valve cylinder head that delivers high levels of intake and exhaust efficiency for ultra-responsive performance.
For instant throttle response, this new high-tech 125 features a compact fuel injection system fed by a large-capacity airbox which, combined with the two inlet valves, delivers optimum intake efficiency together with excellent throttle response across the rev range.
Featuring bore and stroke dimensions of 52mm x 58.6mm, the compact short-stroke engine has a free-revving character that delivers strong acceleration. This short stroke layout – combined with the performance-boosting qualities of the 4-valve head, fuel injection system and free-flowing exhaust – gives the R125 the strongest overall performance in the 125 4-stroke class.
Performance is also enhanced by the fitment of a free-flowing largecapacity R6-style mid-ship muffler, whose location helps to centralise mass for neutral handling performance. The exhaust system accommodates dual catalysers, as well as an air induction system which introduces air into the exhaust to enable more complete combustion of any unburnt gases, and in doing so it helps to reduce emissions to even lower levels.
To optimise the class-leading performance characteristics of its all-new high-tech 125cc liquid-cooled engine, the R125 is equipped with a 6-speed transmission which keeps the engine on the boil and ensures a competitive top speed.