BETA125 RR-S 2017 - Present

　　The 125 RR-S is powered by a 124cc, 4-Stroke, 4-valve, liquid-cooled, single cylinder engine. With a cylinder bore of 2.05 in and stroke of 2.31 in, its motor is undersquare, meaning that the cylinder stroke (length) is greater than the bore (width). This makes the engine less powerful than one of similar displacement with a bigger bore.

　　The 125 RR-S features a double cradle frame made of molybdenum steel. Suspension in the front is provided by an inverted fork measuring 41 mm in diameter. Bringing up the rear is a single shock (monoshock) system. Suspension travel measures 10.3 inches in the front and 10.6 inches in the rear. When it comes to brakes, the 125 RR-S sports a single disc measuring 260 mm in diameter in the front and a single disc measuring 220 mm in the rear.