Generations
- One page for each generation, 1992 to today.
- Body, engine and carburettor change. Read the casting.
- The RS4 and the current bike are four-strokes.
1992 – today
Seven generations, two engines, then a four-stroke.
Years overlap because the sources date some bikes by build and some by registration, and because Italy changed engines before the UK did. Factory codes are the ones the brief takes from the VIN.
GS. Sport Pro is LA. Rotax 123. Dell'Orto VHSB 34
02 · 1995/96–1998Round-light RS 125Late GS, MP0 / MP01, MPA0, MPA1 Rotax 123 for most of Europe and the UK until about 1997–98, or Rotax 122 in Italy from 1995. Dell'Orto VHSB 34 on the 123, or PHBH 28 on the 122
03 · 1999–2005Bee-tailMPB (1999–2002), SF (2003–2005) Rotax 122. Dell'Orto PHBH 28
04 · 2006–2007RSV-stylePY0 open, PYA 11 kW Rotax 122. Dell'Orto PHBH 28
05 · 2007/08–2012Euro 3RD is 11 kW. RM is the open bike. Rotax 122. Dell'Orto VHST 28 with a throttle-position sensor and a carburettor heater
06 · 2011–about 2016RS4 125To verify. Not in the two-stroke VIN table. 124.2 cc DOHC four-valve four-stroke, fuel injection, derived from the Derbi GPR125. Fuel injection. No carburettor.
07 · About 2017–todayRS 125 four-strokeTo verify. The same four-stroke family as the RS4. Euro 5 update in 2021. Euro 5+ update in 2025.. Fuel injection.
Across the two-strokes
MCN’s maintenance guide, as recorded in the brief, says piston rings around every 5,500 miles, piston and barrel around every 10,000 miles, a warm-up to 60°C before hard riding, and a premium two-stroke oil. Those figures are not used on the RS4 or the current four-stroke.
The Derbi D50B0 is the RS50’s 50 cc engine from 2006, not an RS125 engine. The four-stroke RS 125 uses a Derbi GPR125-derived 124.2 cc unit.
Replicas and special editions
Per Hartrusion, as recorded in the research brief, “Replica” means the decal scheme. The mechanical bike is the standard model of that year and code.
| Livery | Years | Generation | Status |
|---|---|---|---|
| Loris Reggiani | 1992 (also a 1995 decal set) | Extrema / GS | Verified |
| Chesterfield | 1994 Extrema, and 1999–2005 bee-tail | Extrema / GS, Bee-tail | Verified. Not listed as a 1998 scheme. |
| Telaio Lucido | 1994 | Extrema / GS | Listed as the polished-frame edition. No separate line in the verification table. |
| Sport Pro | Extrema / GS years | Extrema / GS | Listed as the LA Sport Pro, not as a decal replica. |
| Max Biaggi Chesterfield | 1995–1996 | Round-light RS 125 | Verified |
| Doriano Romboni | 1996 | Round-light RS 125 | Verified (one source) |
| Racing Silver | 1996–1997 | Round-light RS 125 | Listed in the generation record. No separate line in the verification table. |
| Tetsuya Harada | 1998–2000 | Round-light RS 125, Bee-tail | Verified |
| Valentino Rossi | 1998 and 1999 | Round-light RS 125, Bee-tail | Verified |
| Diablo Black | 2001 | Bee-tail | Listed in the generation record. No separate line in the verification table. |
| GP-One / GP1 and SBK | 2003 | Bee-tail | Verified |
| Manuel Poggiali | 2004–2005 | Bee-tail | Verified |
| Marco Melandri | Bee-tail era | Bee-tail | Year to verify To verify |
| Jorge Lorenzo | 2007 | RSV-style | Verified |
| Pista | 2007 | RSV-style | Listed in the generation record. No separate line in the verification table. |
| Spain's No.48 | Filed on the 2007 RSV-style bike; grouped with 2007–2009 schemes | RSV-style | Years to verify To verify |
| Rosso Fluo | 2008 | Euro 3 | Listed in the generation record. No separate line in the verification table. |
| Spain's No.1 | 2007–2009 group | Euro 3 | Years to verify To verify |
| Gabor Talmacsi | 2007–2009 group | Euro 3 | Years to verify To verify |
| Max Biaggi SBK / Alitalia | 2010 | Euro 3 | Verified |
| Full Black | Euro 3 years | Euro 3 | Listed in the generation record. Exact years not given. |
| Full White | Euro 3 years | Euro 3 | Listed in the generation record. Exact years not given. |
| Team Aprilia Alitalia Racing replica | RS4 125 span | RS4 125 | Listed in the generation record. Exact years to verify. To verify |
| Biaggi Racing replica | RS4 125 span | RS4 125 | Listed in the generation record. Exact years to verify. To verify |
| GP Replica | 2017–2018 | RS 125 four-stroke | Listed in the generation record. |
| Loris Capirossi | Unknown | Not assigned | Not verified To verify |
Sources named in the brief: rs125.it, Decalmoto, Motorcyclespecs, 2strokebuzz. 2strokebuzz has no URL in the brief, so it is not linked.