Production since 2011 Class sport bike | ||
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Engine 124.8 cc (8 cu in) Single-Cylinder DOHC four-stroke | ||
The Aprilia RS4 125 is a 125cc class sportbike manufactured by Italian motorcycle firm Aprilia. The RS4 125 is a four-stroke variant of the extremely popular RS125 two-stroke race replica. It is marketed as a tamer, more practical option to the more aggressive, track-oriented RS125. The bike is based on the four-stroke version of the Derbi GPR125. A race kit is available from the manufacturer that boosts power from the standard 15 bhp to 25 bhp.
Specifications
The RS4 125 is available with a quick-shift system similar to the RSV4, in which the engine halts the torque from the engine based on engine rpm, the amount of throttle being applied, and the speed of the bike. This system allows smooth, fast upshifts without the use of the clutch. The chassis is very high-spec, with an aluminium perimeter frame and aluminium swingarm. The brakes are also high-spec, with a 30 cm steel disc in front with a four-piston radial caliper and a 22 cm steel disc with a single caliper at the rear.