The Aprilia RS 125 is a Grand Prix derived replica sports motorcycle powered by a Rotax single-cylinder 124.8 cc two-stroke engine with a Nikasil-coated aluminium cylinder block and liquid cooling. The RS series started in 1992 and the 125 became one of Aprilia’s most successful models.
Aprilia RS 125 at a glance
| Introduced | spring 1992 (Extrema series); production of the 125 from June 1992 |
|---|---|
| Engine | Rotax single-cylinder 124.8 cc two-stroke, liquid-cooled, Nikasil-coated aluminium cylinder |
| Frame (1992) | thin-shell die-cast aluminium frame with reinforcing ribs, floating discs, inverted fork |
| Generations | 1992–1995 Extrema, 1995–1998, 1999–2005, 2006–2012 (two-stroke) |
| Production end of the two-stroke | 2012, replaced by the four-stroke RS4 125 |
| Related models | RS 50, RS 250 (1994–2003, Suzuki twin), RS 125 Tuono (2003–2004) |
| Name | RS stands for the German Rennsport |
The English page dates the first RS 125 to 1992 and the end of the two-stroke to 2012; the Italian page says the RS series ended at the end of 2013 and was replaced by the RS4.
History of the Aprilia RS 125
With the RS series, whose name abbreviates the German Rennsport (racing), Aprilia followed the line of road bikes derived from racing that was popular among young riders in the early 1990s. The RS was meant first of all to replace the dated AF1, and second to take commercial advantage of Aprilia’s racing successes: in 1991 it was second in the world championship in both the 125 and 250 classes, and 1992 brought its first world title.
RS 125 Extrema and Replica, 1992–1995
The Extrema series was shown in spring 1992 and entered production in the 125 version from June 1992, followed in autumn by the Replica Reggiani. It differs from the AF1 in its two-sided swingarm instead of the single-sided one, a new frame and fairings derived from the RSW 125 of 1991. The engine is the known Rotax 123. A Sport Pro set-up was offered for young riders who wanted to race in the Italian Sport Production championship. English Wikipedia describes the first RS 125 as having an angular tail, a square headlight, three-spoke rims and analogue gauges, sold as the red and black RS 125 R.
1995–2012
In 1995 the Extrema name was dropped and the front air intakes were integrated into the fairing. In 1999 the bike was revised with more rounded fairings, five-spoke wheels and a single air duct. The 2006 to 2012 bike has completely new fairings similar to the RSV 1000 R, two headlight bulbs, a digital gauge and multi-spoke wheels, radial four-piston brake calipers and braided brake lines; in 2008 the electronics changed to an EFI Technology ECU and a Dell’Orto 28 mm VHST CD carburettor was fitted to meet Euro 3 rules.
RS4 125 and the four-stroke RS 125
The line was dropped in 2012 to make way for the RS4 125, with a single-cylinder four-stroke fuel-injected engine. For 2019, with the update to Euro 4, the RS4 125 was renamed RS 125 again, keeping the four-stroke engine; it offers better fuel efficiency at the cost of much reduced power and torque compared with the two-stroke, and was updated in 2021 and 2025.
RS 125 Tuono
The RS 125 Tuono, introduced in 2003, was a semi-naked version of the RS 125 with the middle and lower fairing removed and a handlebar on the top yoke. It was produced until 2004.
Design and features
- Engine: a Rotax 124.8 cc two-stroke with a Nikasil-coated cylinder.
- Chassis (1992): a die-cast aluminium frame, floating discs and an inverted fork.
- Racing use: the bike took part in the Italian Sport Production championship and the European championship, and Aprilia ran a one-make cup for the RS 125 and RS 250.
- Brakes (2006): radial four-piston calipers and braided lines.
Aprilia RS 125 versions
- RS 125 Extrema and Replica Reggiani (1992–1995): the first series.
- RS 125 (1995–2012): the following two-stroke generations.
- RS 125 Tuono (2003–2004): the semi-naked version.
- RS4 125 (from 2012) and RS 125 (2019–): the four-stroke bike.
More Aprilia motorcycles are in our Aprilia collection, for example the RS 50, the RS4 125, the AF1 that the RS replaced and the Tuono.
Aprilia RS 125 questions and answers
When was the Aprilia RS 125 introduced?
In 1992, as the Extrema series.
What engine does the RS 125 have?
A Rotax 124.8 cc liquid-cooled two-stroke single; the bike changed to a four-stroke with the RS4 125 in 2012.
What does RS mean?
It comes from the German Rennsport, meaning racing.
What replaced the RS 125 two-stroke?
The RS4 125, which had a four-stroke fuel-injected engine, in 2012.
What is the RS 125 Tuono?
A semi-naked version built in 2003 and 2004.
Sources
- Aprilia RS125, English Wikipedia: generations, Tuono, four-stroke RS 125
- Aprilia RS, Italian Wikipedia: the RS series, Extrema, racing use
