The post-World War II era saw an explosion of minimalist "bubble cars" and cyclecars across Europe and Japan, almost universally relying on compact, fan-assisted or ducted air-cooled motorcycle and industrial engines (often two-stroke singles or twins, along with air-cooled four-stroke units).
Below is an extensive directory organized alphabetically by manufacturer and then by model.
A
ACMA (Ateliers de Construction de Motocycles et Accessoires)
Vespa 400 (France; air-cooled 393 cc two-stroke twin)
Aero Car
Aero Car (United Kingdom; Villiers 197 cc air-cooled single)
Ailloud
Ailloud A3 (France; Sachs 174 cc air-cooled single)
Airway
Airway (United States; 10 hp air-cooled Onan twin)
Alca
Volpe (Italy; 124 cc air-cooled single)
Allard
Clipper (United Kingdom; Villiers 346 cc air-cooled two-stroke twin)
Alta
A200 (Greece; Sachs 191 cc air-cooled single)
Anadol
Böcek (Turkey; Reliant air-cooled utility microcar prototype)
Ardila
Ardila Microcar (Spain; 125 cc air-cooled single)
Autocars
Sussita 12 (Israel; various small air-cooled engine testbeds)
Autobianchi
Bianchina Berlina / Trasformabile / Panoramica / Cabriolet (Italy; Fiat 479 cc / 499 cc air-cooled vertical-twin)
Autoette
Cruise-About (United States; air-cooled single engine versions)
AWS (Automobilwerke Salzgitter)
Piccolo (Germany; Sachs 191 cc air-cooled two-stroke)
Shopper (Germany; Glas 247 cc air-cooled two-stroke single)
B
Bamby
Bamby 1 (United Kingdom; Minarelli 49 cc air-cooled single)
Bantam
Bantam Microcar (United Kingdom; Villiers 122 cc air-cooled single)
Barkas / Framo
V 501 Kleinwagen Prototype (East Germany; air-cooled two-stroke twin)
Bastei
Bastei Microcar (Germany; Sachs 98 cc air-cooled single)
Baur
Baur Microcar (Germany; Fichtel & Sachs 147 cc air-cooled engine)
Beardmore
Minicar (United Kingdom; Villiers air-cooled engine)
Belcar
Belcar (Switzerland; 200 cc Sachs air-cooled single)
Berggren
Fram King Fulda (Sweden; Sachs 191 cc air-cooled single)
Bicar
Bicar Microcar (France; Villiers 98 cc air-cooled single)
Bimobile
Bimobile (Germany; ILO 250 cc air-cooled twin)
Biscuter (Autonacional S.A.)
100 "Zapatilla" (Spain; Hispano Villiers 197 cc air-cooled single)
200 A (Spain; Hispano Villiers 197 cc air-cooled single)
200 C Commercial (Spain; Hispano Villiers 197 cc air-cooled single)
200 F Pegasín Coupé (Spain; Hispano Villiers 197 cc air-cooled single)
200 I Furgoneta (Spain; Hispano Villiers 197 cc air-cooled single)
BMW
600 (Germany; 582 cc air-cooled flat-twin / boxer)
700 / 700 Coupe / 700 LS (Germany; 697 cc air-cooled flat-twin)
Isetta 250 (Germany; 247 cc air-cooled single cylinder four-stroke)
Isetta 300 (Germany; 298 cc air-cooled single cylinder four-stroke)
Bond
Minicar Mark A (United Kingdom; Villiers 122 cc / 197 cc air-cooled two-stroke single)
Minicar Mark B (United Kingdom; Villiers 197 cc air-cooled two-stroke single)
Minicar Mark C (United Kingdom; Villiers 197 cc air-cooled single)
Minicar Mark D (United Kingdom; Villiers 197 cc air-cooled single)
Minicar Mark E (United Kingdom; Villiers 197 cc air-cooled single)
Minicar Mark F (United Kingdom; Villiers 247 cc air-cooled single)
Minicar Mark G (United Kingdom; Villiers 247 cc air-cooled single / twin)
Boudot
Velocar (France; Motobécane 125 cc air-cooled single)
Brütsch
Bussard (Germany; Sachs 191 cc air-cooled single)
Mopetta (Germany; ILO 49 cc air-cooled single)
Pfeil (Germany; Sachs 191 cc or Lloyd 250 cc air-cooled twin)
Rollera (Germany; Sachs 98 cc / 102 cc air-cooled single)
Spatz (Germany; Sachs 191 cc / Fichtel & Sachs 200 cc air-cooled)
Zwerg (Germany; Sachs 191 cc air-cooled single)
C
Canta
Canta LX (Netherlands; Honda 160 cc / 200 cc air-cooled single)
Casalini
Sulky (Italy; Minarelli / Piaggio 49 cc air-cooled single)
CBR
CBR Kleinstwagen (Germany; ILO 250 cc air-cooled twin)
Champion
Ch-1 (Germany; Triumph 200 cc air-cooled two-stroke)
Ch-2 (Germany; Triumph 250 cc air-cooled two-stroke)
250 (Germany; ILO 250 cc air-cooled two-stroke)
400 / 400 H (Germany; ILO 396 cc air-cooled two-stroke twin)
Chausson
CHS Petite Voiture (France; 2-stroke air-cooled single prototype)
Cimatti
City-Car (Italy; Morini 49 cc air-cooled single)
Claude
Claude Minicar (France; Sachs 125 cc air-cooled single)
Claveau
Petit Véhicule (France; 125 cc air-cooled single)
Coudert
Voiturette (France; Motobécane 125 cc air-cooled single)
Crossley
Tiddler (United Kingdom; Villiers 197 cc air-cooled single prototype)
Csepel
Balaton (Hungary; Pannonia 250 cc air-cooled single)
D
Daihatsu
Midget DKA / MP series (Japan; 249 cc / 305 cc forced-air-cooled single)
De La Chapelle
Parcours / Junior (France; Honda air-cooled single)
Denzel
WD Super (Austria; air-cooled Volkswagen/Porsche flat-four derivative)
Dornier
Delta (Germany; Sachs 191 cc / Zündapp 250 cc air-cooled single prototype; evolved into the Zündapp Janus)
DUO (VEB Robur-Werke)
DUO 4/1 (East Germany; Simson 50 cc fan-cooled two-stroke single)
DUO 4/2 (East Germany; Simson 50 cc fan-cooled two-stroke single)
Durocar
Durocar (Switzerland; air-cooled 175 cc single)
E
Elva
Courier Minicar (United Kingdom; Villiers 250 cc air-cooled twin prototype)
Enzmann
506 (Switzerland; Volkswagen 1,192 cc air-cooled flat-four)
ERA
E.R.A. Kleinstwagen (Germany; ILO 200 cc air-cooled single)
Esperanza
Microcar (Spain; Villiers 197 cc air-cooled single)
F
Fend
Flitzer 100 (Germany; Sachs 98 cc air-cooled single)
Flitzer 101 (Germany; Riedel 98 cc / Sachs 98 cc air-cooled single)
Fiat
500 "Topolino" (Italy; primarily water-cooled, but included experimental air-cooled models)
500 Nuova / D / F / L / R (Italy; 479 cc / 499 cc / 594 cc air-cooled vertical-twin)
126 (Italy/Poland; 594 cc / 652 cc air-cooled vertical-twin)
FMR (Fahrzeug- und Maschinenbau GmbH Regensburg)
Tg500 "Tiger" (Germany; Fichtel & Sachs 494 cc air-cooled two-stroke twin)
Frisky (Meadows / Henry Meadows Ltd.)
Family Three (United Kingdom; Villiers 197 cc / 249 cc / 324 cc air-cooled twin)
Frisky Sport (United Kingdom; Villiers 324 cc air-cooled twin)
Frisky Sprint (United Kingdom; Villiers 492 cc air-cooled three-cylinder prototype)
Prince (United Kingdom; Villiers 324 cc air-cooled twin)
Fuji Heavy Industries (Subaru)
360 (Japan; EK31 / EK32 356 cc forced-air-cooled two-stroke straight-twin)
360 Custom / Sambar (Japan; EK32 356 cc air-cooled two-stroke twin)
Fuldamobil (Elektromaschinenbau Fulda)
N-1 (Germany; Baker & Pölling 200 cc / Sachs 191 cc air-cooled single)
N-2 (Germany; Fichtel & Sachs 191 cc air-cooled single)
S-1 (Germany; Sachs 191 cc air-cooled single)
S-2 (Germany; Sachs 191 cc air-cooled single)
S-3 (Germany; Sachs 191 cc air-cooled single)
S-4 (Germany; Sachs 191 cc air-cooled single)
S-6 (Germany; Sachs 191 cc air-cooled single)
S-7 (Germany; Fichtel & Sachs 191 cc or Heinkel 200 cc air-cooled single)
G
Galy
V2C (France; 250 cc air-cooled single)
Glas (Hans Glas GmbH)
Goggomobil Coupé TS 250 / TS 300 / TS 400 (Germany; 247 cc / 293 cc / 392 cc forced-air-cooled two-stroke twin)
Goggomobil Dart (Australia; Glas 293 cc / 392 cc air-cooled twin)
Goggomobil Limousine T 250 / T 300 / T 400 (Germany; 247 cc / 293 cc / 392 cc forced-air-cooled two-stroke twin)
Goggomobil Transporter TL 250 / TL 300 / TL 400 (Germany; 247 cc / 293 cc / 392 cc air-cooled twin)
Gordon
Gordon Three-Wheeler (United Kingdom; Villiers 197 cc air-cooled single)
Gnom
Gnom Microcar (Germany; Fichtel & Sachs 98 cc air-cooled single)
Grof
Microcar (Austria; Puch 250 cc air-cooled split-single)
Gutbrod
Superior 600 (Germany; 593 cc air-cooled two-stroke twin)
H
Harper
Scootacar (United Kingdom; Villiers 197 cc air-cooled single)
Hata
Hata-Jidosha (Japan; air-cooled 200 cc single)
Heinkel
Kabine Type 150 (Germany; 174 cc four-stroke fan-cooled single)
Kabine Type 153 (Germany; 198 cc / 204 cc four-stroke fan-cooled single)
Kabine Type 154 (Germany; 198 cc / 204 cc four-stroke fan-cooled single)
Hoffmann
Auto-Kabine (Germany; ILO 250 cc air-cooled single)
Hope Motor Company
HopeStar ON 360 (Japan; Mitsubishi ME24 359 cc air-cooled two-stroke twin; pre-Suzuki Jimny)
HopeStar SY / SM (Japan; 360 cc air-cooled single)
Hotzenblitz
Hotzenblitz Micro (Germany; Sachs air-cooled engine test prototypes)
Husqvarna
Husqvarna Microcar (Sweden; 250 cc air-cooled two-stroke prototype)
I
Inter
175A Berline / Autoscooter (France; Ydral 175 cc fan-cooled two-stroke single)
Isetta of Great Britain
Isetta Plus / 300 / 4-Wheeler (United Kingdom; BMW 298 cc air-cooled single)
Iso Autoveicoli
Isetta (Italy; Iso 236 cc fan-cooled split-single two-stroke)
Isocarro (Italy; Iso 236 cc air-cooled split-single two-stroke)
Italsuisse
Microcar Prototype (Italy; Sachs 200 cc air-cooled engine)
J
Jawa
Minicar Prototype (Czechoslovakia; Jawa 250 cc / 350 cc air-cooled two-stroke)
Julienne
Microcar (France; Sachs 125 cc air-cooled single)
K
Kewet
El-Jet (Denmark; primarily EV, early range-extender prototypes used Sachs air-cooled engines)
King
King Cab (Sweden; Sachs 191 cc air-cooled single; licensed Fuldamobil S-7)
Kisen
Kisen Microcar (Germany; ILO 125 cc air-cooled single)
Kleinschnittger
F 125 (Germany; ILO 123 cc air-cooled two-stroke single)
F 250 (Germany; ILO 248 cc air-cooled two-stroke twin)
Koller
Koller Microcar (Germany; Sachs 191 cc air-cooled single)
Kover
Capucine (France; Ydral 125 cc air-cooled single)
Kroboth
Allwetterroller (Germany; Sachs 174 cc air-cooled single)
L
Lamkarto
Microcar (France; Sachs 98 cc air-cooled single)
Libelle
Libelle (Austria; Rotax-Sachs 197 cc air-cooled single)
Ligier
JS4 (France; Motobécane 49 cc air-cooled single)
JS6 (France; Derbi 49 cc air-cooled single)
Lloyd
LP 250 (Germany; 250 cc air-cooled two-stroke twin)
LP 300 (Germany; 293 cc air-cooled two-stroke twin)
LP 400 (Germany; 386 cc air-cooled two-stroke twin)
LP 600 / Alexander (Germany; 596 cc air-cooled four-stroke parallel twin)
LT 500 / LT 600 (Germany; 596 cc air-cooled four-stroke parallel twin)
M
Maico
MC 125 (Germany; Maico 123 cc air-cooled single)
MC 400 (Germany; ILO 396 cc air-cooled two-stroke twin)
Champion 400 H (Germany; ILO 396 cc air-cooled two-stroke twin)
Manta
Manta Mopedauto (Germany; Sachs 50 cc air-cooled single)
Markus
Markus Microcar (Germany; Sachs 191 cc air-cooled single)
Mazda (Toyo Kogyo)
B360 (Japan; 356 cc BA-series air-cooled overhead-valve V-twin)
K360 (Japan; 356 cc BA-series air-cooled overhead-valve V-twin)
R360 Coupe (Japan; 356 cc forced-air-cooled 90° V-twin four-stroke)
Messerschmitt
KR175 (Germany; Fichtel & Sachs 174 cc air-cooled two-stroke single)
KR200 (Germany; Fichtel & Sachs 191 cc air-cooled two-stroke single)
KR201 Roadster (Germany; Fichtel & Sachs 191 cc air-cooled two-stroke single)
Meyra
Meyramobil 200 (Germany; ILO 197 cc air-cooled single)
Mochet
Type K (France; Ydral 125 cc air-cooled single)
Type KM (France; Ydral 125 cc air-cooled single)
Type CM (France; Ydral 175 cc air-cooled single)
Monocar
Monocar (United Kingdom; Villiers 197 cc air-cooled single)
Möve
Möve 100 (Germany; Fichtel & Sachs 98 cc air-cooled single)
N
Nardi
750 Chiti (Italy; Fiat air-cooled based special)
Neustadt
Piccolo (Germany; Sachs 147 cc air-cooled single)
New Map
Solyto (France; Ydral 125 cc / Motobécane 125 cc air-cooled single)
Rolux (France; Ydral 125 cc air-cooled single)
Nobel
200 (United Kingdom/Chile; Sachs 191 cc air-cooled single; licensed Fuldamobil)
Norsjö
Shopper / Carrier (Sweden; Sachs 47 cc / Husqvarna 50 cc air-cooled single)
NSU
Prinz I / Prinz II / Prinz III (Germany; 583 cc air-cooled vertical-twin)
Prinz 4 / 4L (Germany; 598 cc air-cooled vertical-twin)
O
O.P.E.C.
Colibri (France; Ydral 125 cc air-cooled single)
Opperman
Unicar (United Kingdom; Excelsior 328 cc air-cooled two-stroke twin)
Stirling (United Kingdom; Excelsior 328 cc air-cooled two-stroke twin)
P
Pawi
Pawi Kleinstwagen (Germany; ILO 250 cc air-cooled twin)
Peel Engineering Company
P50 (Isle of Man; DKW 49 cc fan-cooled single)
Trident (Isle of Man; Triumph / DKW 49 cc or Minarelli 98 cc air-cooled single)
Perry
Perry Microcar (United Kingdom; Villiers 197 cc air-cooled single)
Peta
Peta Microcar (Germany; ILO 200 cc air-cooled single)
Pfeil
Pfeil Microcar (Austria; Puch 125 cc air-cooled single)
Poinard
Voiturette (France; Motobécane 125 cc air-cooled single)
Powerdrive
Powerdrive (United Kingdom; British Anzani 322 cc air-cooled twin)
Puch
500 / 650 TR (Austria; Steyr-Puch 493 cc / 643 cc air-cooled boxer-twin)
R
Ravel
Ravel Minicar (France; Sachs 125 cc air-cooled single)
Reliant
Regal Mark I – Mark VI (United Kingdom; early prototypes and auxiliary-fan test units; main line water-cooled 747 cc)
Reyonnah
175 (France; AMC 175 cc air-cooled four-stroke single)
Rovin
D2 (France; 425 cc air-cooled flat-twin)
D3 (France; 462 cc air-cooled flat-twin)
D4 (France; 462 cc air-cooled flat-twin)
Rune
Microcar (Sweden; Husqvarna 118 cc air-cooled single)
S
S.A.M.C.A.
Chariot (France; Ydral 125 cc air-cooled single)
Sachsenring (AWZ)
P70 Zwickau (East Germany; 684 cc water-cooled predecessor, test prototypes tested air-cooled twin)
Trabant 500 (P50) (East Germany; 499 cc air-cooled two-stroke twin)
Trabant 600 (P60) (East Germany; 594 cc air-cooled two-stroke twin)
Trabant 601 (East Germany; 594 cc air-cooled two-stroke twin)
Scootacar
Mark I (United Kingdom; Villiers 197 cc air-cooled single)
Mark II / De Luxe (United Kingdom; Villiers 247 cc air-cooled single)
Mark III (United Kingdom; Villiers 324 cc air-cooled twin)
Sears
Allstate (United States; Steyr-Puch 500 cc air-cooled flat-twin badged model)
Servicar
Servicar Micro (Spain; Hispano Villiers 197 cc air-cooled single)
Shelvoke & Drewry
Minicar (United Kingdom; Villiers 147 cc air-cooled single)
SMZ (Serpukhov Motor Works)
S-1L (Soviet Union; IZh-49 123 cc air-cooled single)
S-3A (Soviet Union; IZh-56 346 cc air-cooled single)
S-3D (Soviet Union; IZh-Planeta-2 / Planeta-3 346 cc fan-cooled two-stroke single)
Snoopy
Microcar (Netherlands; Sachs 50 cc air-cooled single)
Spandau
Spandau Microcar (Germany; Sachs 98 cc air-cooled single)
Spatz (Victoria)
200 (Germany; Fichtel & Sachs 191 cc air-cooled single)
Steyr-Daimler-Puch
Steyr-Puch 500 / 500D (Austria; 493 cc air-cooled flat-twin)
Steyr-Puch 650 TR II (Austria; 643 cc air-cooled flat-twin)
Steyr-Puch Haflinger 700 AP (Austria; 643 cc air-cooled boxer-twin utility micro-vehicle)
Subaru
R-2 (Japan; early series EK33 356 cc forced-air-cooled two-stroke twin)
Suzuki
Fronte 360 (Japan; LC10 356 cc air-cooled two-stroke three-cylinder)
Suzulight SF / 360 (Japan; 360 cc air-cooled two-stroke twin)
Suzulight Carry FB (Japan; 359 cc air-cooled two-stroke twin)
T
Taylor
Aerocar (United States; air-cooled flat-four aircraft engine)
Tempo
Hanseat (Germany; ILO 396 cc air-cooled twin)
Tjorven (Kalmar Mekaniska Verkstad)
KVD 440 / 441 (Sweden; DAF 844 cc air-cooled boxer-twin)
Townsend
Townsend Barchetta (United Kingdom; Villiers 197 cc air-cooled single)
Trippel
SK 10 (Germany; Zündapp / ILO 200 cc air-cooled single)
V
Velorex (Velo Stadion)
Oskar 54 (Czechoslovakia; Jawa 250 cc air-cooled single)
16/250 (Czechoslovakia; Jawa 249 cc air-cooled single)
16/350 (Czechoslovakia; Jawa 344 cc air-cooled twin)
Victoria
250 (Germany; ILO 250 cc air-cooled twin)
Voisin
Biscooter (France; Gnome et Rhône 125 cc air-cooled single prototype; precursor to the Spanish Biscuter)
W
Wendax
Aero / Piccolo (Germany; ILO 250 cc air-cooled single)
Wikov
Baby (Czechoslovakia; air-cooled prototype)
Z
Zapatin
Zapatin Microcar (Spain; Villiers 125 cc air-cooled single)
Zeta
Runabout (Australia; Sachs 191 cc air-cooled single)
Sedan (Australia; Villiers 324 cc air-cooled two-stroke twin)
Sports (Australia; Sachs 498 cc air-cooled two-stroke twin)
Utility (Australia; Villiers 324 cc air-cooled two-stroke twin)
Zündapp
Bella-Car (Germany; Zündapp 198 cc air-cooled single prototype)
Janus 250 (Germany; Zündapp 245 cc fan-cooled two-stroke single)