Editing Alfa Romeo RL & RM/Chassis Registry/Chassis/RM/12135 (section)

= Alfa Romeo RM Sport Torpedo chassis 12135 =

{{ChassisEntry
| manufacturer = Alfa Romeo
| model = Alfa Romeo RL & RM
| variant = RM Sport (short chassis)
| year = 1924
| chassis = 12135
| engine = 12239
| gearbox = Alfa Romeo RM 4-speed manual (replacement, period-correct)
| body = Torpedo (short chassis)
| coachbuilder = Unknown (possibly Castagna or Zagato; unconfirmed)

| engine_size_original = 1,944 cc (44 bhp specification)
| engine_size_current  = 1,944 cc (replacement RM engine)

| body_style_original = Sport Torpedo (short wheelbase)
| body_style_current  = Sport Torpedo (largely original body retained)

| colour_original = Unknown
| colour_current  = Unrestored / project condition

| interior_original = Period leather trim
| interior_current  = Partially original leather and woodwork retained

| first_completed = 1924
| first_delivered = Unknown
| first_destination = Italy
| original_registration = Italian libretto (1950s agricultural registration recorded)

| notes_short = Rare short-chassis RM Sport Torpedo; discovered in Rovigo in 1972; originally missing engine; fitted with correct RM engine no. 12239; partial restoration undertaken.

| blurb = A 1924 Alfa Romeo RM Sport Torpedo, chassis 12135, one of the scarce short-chassis Sport variants, discovered in Italy in 1972 and currently in partially restored project condition.

| registry_page = Alfa Romeo RL & RM/Chassis Registry
}}

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== Ownership history ==

{| class="wikitable sortable"
! No. !! Owner !! Location !! Occupation / Notes !! From !! To
|-
| 1 || Early owner(s) unknown || Italy || Original period ownership undocumented || 1924 || 1950s
|-
| 2 || Private owner || Italy || Vehicle reportedly used for agricultural purposes; Italian libretto records this use || 1950s || 1972
|-
| 3 || Vendor’s family || Rovigo, Italy || Discovered vehicle; retained and commenced restoration || 1972 || Present (at time of sale)
|}

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== Registration history ==

{| class="wikitable sortable"
! Registration !! Location !! From !! To !! Notes
|-
| Italian libretto (number unrecorded) || Italy || 1950s || — || Listed for agricultural use
|}

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== Competition history (period) ==

No confirmed individual competition history documented for chassis 12135.

The RM Sport model made its sporting debut at the Coppa delle Alpi in 1923, finishing 4th in the 2-Litre category, and many of the approximately 500 RM models produced were used in competition.

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== Appearances and non-competitive events ==

No confirmed historic event participation recorded.

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== Restoration and mechanical history ==

* Discovered in the province of Rovigo, Italy in 1972.
* At time of discovery the original engine was missing.
* A 1950s Alfa Romeo 1900 engine was initially installed.
* In the 1980s restoration commenced:
  * Body removed from chassis
  * Chassis repaired as necessary
  * Steering box fully overhauled
  * Differential and half-shafts restored
* A correct Alfa Romeo RM engine (no. 12239) and matching gearbox were later sourced and installed.
* Much of the body structure remains original, including:
  * Doors with original wooden framework
  * Original leather panels
  * Some original instrumentation

Vehicle remains in partially restored project condition.

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== Technical specification ==

The RM Sport differed from the RM Normale through:

* Raised compression ratio
* Increased output (approximately 44 bhp)
* Shorter wheelbase
* Improved sporting performance

The RM range (introduced 1923) featured:

* 1,944 cc four-cylinder overhead-valve engine
* Four-speed manual transmission
* Ladder-frame chassis
* Mechanical drum brakes
* Top speed approximately 90 km/h (56 mph)

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== Historical significance ==

Chassis 12135 represents one of the scarce surviving short-chassis RM Sport Torpedo variants. Two similar examples are recorded in the Alfa Romeo Museum collection at Arese.

Its survival through mid-century agricultural conversion and subsequent rediscovery provides insight into the post-war secondary life of early Alfa Romeo sporting cars.

As a largely original-bodied example fitted with a correct RM engine, it constitutes an important restoration candidate within the early Alfa Romeo four-cylinder lineage.

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== Notes ==

* Coachbuilder attribution (Castagna or Zagato) remains unconfirmed.
* Engine no. 12239 is not documented as original to chassis 12135.
* Original engine number currently unknown.
* Approximately 500 RM models produced (Normale, Sport, Unificato combined).
* RM chassis number range recorded as 12001–12265.

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== Sources ==

* Auction catalogue description (1924 Alfa Romeo RM Sport Torpedo)
* Italian registration documentation (libretto, 1950s)
* RM production summaries