Item | Spec to Spec | Engine No to Engine No | Part No | Replaced By |
| Breather | 10 to 12 | 80000 to 96074 | D104 | 10-2-245C |
| Breather Vacuum type | 12 to 13 | 96075 to 98999 | 3118 | N/A |
| Breather | 13 to 18 | 99000 to 139699 | D104 | D/986 Cover |
| Breather Fitted on valve cover | 13 to date | 99000 to date | 10-2-245c | Used with air cleaners |
| Cam Rocker Lever | 10 to Date | 80000 to Date | D32c | Spiral Gear Drive |
| Cam Rocker Lever | 22 to 25 only | N/A | 105/32c | Spur Gear Drive |
| Camshaft Clockwise Rotation | 10 to Date | 80000 to Date | D31 | See gear case drive details |
| Camshaft Anti-Clockwise Rotation | 10 to Date | 80000 to Date | D31R | See gear case drive details |
| Camshaft | 22 to 25 only | N/A | 1/1010 | See gear case drive details |
| Carburettor Suction type no float chamber | 10 to 11 | 80000 to 94119 | D65C | N/A |
| Choke Tube 700rpm | 10 to 11 | 80000 to 94119 | D169 | D170 |
| Choke Tube 1000rpm | 10 to 11 | 80000 to 94119 | D170 | N/A |
| Carburettor Amal Float Chamber type | 12 to 13 | 94120 to 114999 RH Rotation 700rpm | D261 | 1/802 |
| Carburettor Amal Float Chamber type | 12 to 13 | 94120 to 114999 RH Rotation 1000rpm | D262 | 1/802 |
| Carburettor Amal Float Chamber type | 12 to 13 | 94120 to 114999 LH Rotation 700rpm | D263 | 1/804 |
| Carburettor Amal Float Chamber type | 12 to 13 | 94120 to 114999 LH Rotation 1000rpm | D264 | 1/804 |
| Carburettor Solex 26FV type | 16 to 17 | 115000 to 118999 | 1/718 | N/A |
| Carburettor Amal Float Chamber type | 18 to 28 | 119000 to 1/24982 RH Rotation 700rpm | 1/801 | 1/802 |
| Carburettor Amal Float Chamber type | 28 to Date | 1/24983 to Date RH Rotation 700rpm | 1/802 | Current |
| Carburettor Amal Float Chamber type | 18 to Date | 119000 to Date RH Rotation 1000rpm | 1/802 | Interchangeable with D262 |
| Carburettor Amal Float Chamber type | 18 to 28 | 119000 to 1/24982 LH Rotation 700rpm | 1/803 | 1/804 |
| Carburettor Amal Float Chamber type | 18 to 28 | 1/24983 to Date LH Rotation 700rpm | 1/804 | Current |
| Carburettor Amal Float Chamber type | 18 to Date | 119000 to Date LH Rotation 1000rpm | 1/804 | Interchangeable with D264 |
| Crankcase | 10 to 12 | 80000 to 94119 | D1s | 1/1054 & List 24 |
| Crankcase | 12 Only | 94120 to 97999 | D501s | 1/1054 & List 189 |
| Crankcase | 13 to 16 | 98000 to 116999 | 1/1054 | 1/1054 & List 190 |
| Crankcase | 17 to Date | 117000 to Date | D602S | Current |
Item | Spec to Spec | Engine No to Engine No | Part No | Replaced By |
| Crankcase Non-Automatic Plant with CI radiator | N/A | 80000 to 94119 | D1 | 1/1057 & List 339 |
| Crankcase Non-Automatic Plant with CI radiator | N/A | 94120 to 97999 | D1 | 1/1057 & List 340 |
| Crankcase Non-Automatic Plant with CI radiator | N/A | 98000 to 116999 | 1/1057 | 1/1057 & List 341 |
| Crankcase Non-Automatic Plant with CI radiator | N/A | 117000 to Date | 1/1058 | Current |
| Crankcase Non-Automatic Plant, non-CI radiator | N/A | 117000 to Date | D602 | N/A |
| Crankcase Automatic Plant with CI radiator | N/A | 80000 to 94119 | D1 | 1/1055 & List 191 |
| Crankcase Automatic Plant with CI radiator | N/A | 94120 to 97999 | D1 | 1/1055 & List 192 |
| Crankcase Automatic Plant with CI radiator | N/A | 98000 to 116999 | 1/1055s | 1/1055 & List 193 |
| Crankcase Automatic Plant with CI radiator | N/A | 117000 to Date | 1/1056 | Current |
| Crankcase Automatic Plant non-CI radiator | N/A | 117000 to Date | 1/1235 | N/A |
Item | Spec to Spec | Engine No to Engine No | Part No | Replaced By |
| Crankshaft With split ring on Crankpin | 10 to 13 | 80000 to 99586 | D21 | D221 with D219, D220 & S1127 |
| Crankshaft With Split ring and for Direct Coupling | 10 to 13 | 80000 to 101887 | D383 | D483 with D219, D220 & S1127 |
| Crankshaft With Sleeve D33 and Split Ring D30 | 13 to Date | 99587 to Date | D221 | Current |
| Crankshaft With Sleeve D33 and Split Ring D30 for Direct Coupling | 13 to Date | 101888 to Date | D483 | Direct Coupled only |
| Crankshaft Cast Iron | 26 Only | 183348 to 186351 Used from 18/6/43 to 21/12/43 | D221/1 | D221 |
| Oil Thrower Ring Used on D21 and D383 | 10 to 13 | 80000 to 99586 | D22 | N/A |
| Oil Thrower Ring Used on D221 and D483 | 13 to date | 99587 to Date | D219 | N/A |
| Main Bearing Flywheel end (Small) | 10 to Date | 80000 to Date | D7 | 1½" x 3¼" x ¾" |
| Main Bearing Crankpin end (Large) | 10 to Date | 80000 to Date | D8 | 1¾" x 3¾" x 13/16" |
| Bearing Housing | 10 to 13 | up to 95529 | D6 | With 6 studs |
| Bearing Housing | 13 to Date | 95530 on | D6 | With 5 studs |
| Cylinder Head | 10 to 11 | 80000 to 94119 | D9s | 1/1062 and List 15 |
| Cylinder Head | 12 to 13 | 94120 to 110578 | 1/1153s | 1/1062 and List 16A |
| Cylinder Head | 13 to 18 | 110579 to 141868 | D309s | 1/1062 and plug 27/1968 |
| Cylinder Head | 23 to Date | 141869 to Date | 1/1062s | Current |
| Valve Inlet | 10 to 11 | 80000 to 92499 | D55 IN | D155 IN |
| Valve Exhaust | 10 to 11 | 80000 to 92499 | D55 EX | D255 EX |
| Valve Inlet | 11 to Date | 92500 to Date | D155 IN | Current |
| Valve Exhaust | 11 to 12 | 92500 to 98822 | D155 EX | D255 EX |
| Valve Exhaust | 13 to Date | 98823 to Date | D255 EX | With Thinner Head |
| Valve Spring | 10 to 11 | 80000 to 94119 | D156 | N/A |
| Valve Spring | 12 Only | 94120 to 97999 | D311 | D323 |
| Valve Spring | 13 to Date | 98000 to Date | D323 | Current |
| Valve Spring Carrier, Bottom | 10 to 11 | 80000 to 94119 | D54 | N/A |
| Valve Spring Carrier, Top | 10 to 11 | 80000 to 94119 | D57 | N/A |
| Valve Spring Carrier | 12 to Date | 94120 to Date | D312 | N/A |
| Valve Rocker Lever With Bush D64 | 10 only | 80000 to 88080 | D58c | N/A |
| Valve Rocker Lever With Bush D64 & Striking Pin D157 | 10 to 11 | 88081 to 92499 | D58c | Striking Pin Introduced |
| Valve Rocker Lever With Bush D64 & Striking Pin 5-1/B130 | 12 to Date | 94120 to date | D158c | Current |
| Valve Rocker Shaft Distance Piece | 10 to 11 | 80000 to 94119 | D61 | N/A |
| Valve Rocker Shaft Centre Collar | 12 to Date | 94120 to Date | D313 | Current |
| Valve Rocker Shaft End Collar | 12 to Date | 94120 to Date | D314 | Current |
| Valve Push Rod with end cap D59 | 10 to 11 | 80000 to 94119 | D62c | N/A |
| Valve Push Rod with end cap D59 | 12 to Date | 94120 to Date | D315c | Use with Spiral Gear Magneto Drive, see gear listing |
| Valve Push Rod | 22 to 25 ONLY | 140956 to 155207 | 1/980c | Use with Spur Gear Magneto Drive, see gear listing |
| Cylinder Head Valve Rocker and Water Jacket Cover, Hopper Cooling | 10 to 12 | 80000 to 96074 | D110 | D112H + 1/986 |
| Cylinder Head Valve Rocker Cover Tank/Rad Cooling | 10 to 18 | 80000 to 139699 | D111 | Used for Special Orders use 1/986 if no air cleaner |
| Cylinder Head Valve Rocker Cover Hopper Cooling (with Cover D104) | 12 to 18 | 96075 to 139699 | D111 | 1/986 |
| Cylinder Head Valve Rocker Cover Tank/Rad/Hopper Cooling | 18 to Date | 139700 to Date | 1/986 | Current |
| Cylinder Head Water Jacket Cover Aux Hopper Cooling | 10 to Date | 80000 to Date | D560 | Current |
| Cylinder Head Water Jacket Cover Radiator Cooling | 10 to 16 | 80000 to 116999 | F112 | N/A |
| Cylinder Head Water Jacket Cover Radiator Cooling | 17 to Date | 117000 to Date | D210 | Current |
| Cylinder Head Water Jacket Cover Tank Cooling | 10 to Date | 80000 to Date | D112 | Current |
| Cylinder Head Water Jacket Cover Hopper Cooling | 12 to Date | 96075 to Date | D112H | Current |
| Engine Governor Complete 500rpm | 10 Only | 80000 to 80999 | D269/1 | N/A |
| Engine Governor Complete 500rpm | 11 to 13 | 81000 to 114999 | D269/2 | N/A |
| Engine Governor Complete 500rpm | 16 to Date | 115000 to Date | D269/3 | Current |
EXCEPT:- | 22 to 25 | 140942 to 140955 140956** to 155207** ** only if Spur gears fitted | N/A | **See Gear Listing |
| Engine Governor Housing for spur gear drive | 22 to 25 | See gear drive listing | 1/1000 | N/A |
| Engine Governor Governor spring 500rpm | 22 to 25 | See gear drive listing | D447 | N/A |
| Engine Governor Governor spring 700rpm 1½hp | 22 to 25 | See gear drive listing | D147 | N/A |
| Engine Governor Governor spring 1000rpm 2hp | 22 to 25 | See gear drive listing | D47 | N/A |
| Engine Governor Fittings Spiral Gear Drive - Governor Rod Bare | 10 to 13, 18 to Date Except: 22 to 25 | 80000 to 114999 and 119000 to Date Except for: 140942 to 155207 | 1/800 | Current |
| Governor Rod with levers D42 & D244 | 10 to 11 | 80000 on | D44 | Lister Carb |
| Governor Rod with levers D42 & D244 | 12 to 13 | to 114999 | D44 | Lister Carb |
| Governor Rod with levers D42 & D244 | 16 to 17 | 115000 to 118275 | D530c | Solex Carb |
| Governor Rod Bare, Clock & Anti-Clock | 16 to 17 | 115000 to 118275 | D530 | N/A |
| Governor Rod with levers D42, D244 For Petrol Clock and Paraffin Anti-Clock engines | 18 to Date Except 22 to 25 | to 119000 to Date Except 140942 to 155207 | 1/840 | Current |
| Governor Rod with levers D42, D244 For Petrol Anti-Clock and Paraffin Clock engines | 18 to Date Except 22 to 25 | to 119000 to Date Except 140942 to 155207 | 1/841 | Current |
| Governor Rod Lever, Governor end with Roller 3172 & Pin D107 | 10 to Date Except 22 to 25 | 80000 to Date Except 140942 to 155207 | D42c | Current |
| Governor Rod Lever, Throttle end | 10 to 13 Except 22 to 25 | 80000 to 114999 Except 140942 to 155207 | D244 | Current |
| Governor Rod Lever, Throttle end | 16 to 17 Except 22 to 25 | 115000 to 118275 Except 140942 to 155207 | D534 | N/A |
| Governor Rod Lever, Throttle end | 18 to Date Except 22 to 25 | 119000 to Date Except 140942 to 155207 | D244 | Current |
| Governor Outside Spring 500rpm | 10 to Date Except 22 to 25 | 80000 to Date Except 140942 to 155207 | 3174 | Current |
| Governor Outside Spring 700rpm | 10 to Date Except 22 to 25 | 80000 to Date Except 140942 to 155207 | 3174 | Current |
| Governor Outside Spring 1000rpm | 10 to Date Except 22 to 25 | 80000 to Date Except 140942 to 155207 | J127 | Current |
| Governor Outside Spring 1100 to 1250 rpm | to Date Except 22 to 25 | to Date Except 140942 to 155207 | T192 | Current |
| Throttle Rod Vertical | 10 to 13 Except 22 to 25 | 80000 to 114999 | D70 | Current |
| Throttle Rod Vertical | 16 to 17 Except 22 to 25 | 115000 to Date | D478 | Current |
| Throttle Rod Vertical | 18 to Date Except 22 to 25 | 119000 to Date | D70 | Current |
| Governor Rod Lever, Throttle end | 22 to 25 | 140492 to 155207 | 1/1037 | N/A |
| Governor Rod with levers for Clock and Anti-Clock engines | 22 to 25 | 140942 to 155207 | 1/1039c | N/A |
| Governor Rod Bare | 22 to 25 | 140492 to 155207 | 1/1039 | N/A |
| Throttle Connecting Rod | 22 to 25 | 140492 to 155207 | 105/353 | N/A |
| Governor Rod Lever, Governor end with Roller 3172 & Pin D107 | 22 to 25 | 140942 to 155207 | D42c | Current |
| Magneto Clockwise same rotation as engine | 10 Only | 80000 to 80999 | ML No Part No | Replace by RS1 |
| Magneto opposite rotation to engine | 11 to 13 | 81000 to 101357 | ML No Part No | Replace by RS1 |
| Magneto opposite rotation to engine | 13 Only | 101358 to 114999 | MK1 | Replace by RS1 |
| Magneto opposite rotation to engine | 16 Only | 115000 to 116999 | MK1 SW With switch | Replace by RS1 |
| Magneto same rotation as engine | 17 Only | 117000 to 118999 | MK1 SW With switch | Replace by RS1 |
| Magneto same rotation as engine | 18 Only | 119000 to 134696 | MK1 No switch | Replace by RS1 |
| Magneto same rotation as engine | 18 Only | 134697 to 136198 | MK1 or RS1 | Replace MK1 by RS1 |
| Magneto same rotation as engine | 18 to Date | 136199 to Date | RS1 | Current |
| Fuel Tank ¾ gallon mounted on starting handle bracket | 10 to 11 | 80000 to 92000 | D92 | Replace by A93 |
| Fuel Tank 1 gallon mounted on starting handle bracket | 11 to 13 | 92001 to 110578 | A93 | N/A |
| Fuel Tank, C/W Rotation Engine Strapped to Cyl Head | 13 to 18 | 110579 to 140051 | 1/291 | Replaced by 1/1059 |
| Fuel Tank, A/C/W Rotation Engine Strapped to Cyl Head | 18 Only | 119000 to 140051 | 1/285 | Replaced by 1/1059 |
| Fuel Tank, with filter Strapped to Cyl Head | 18 to 20 | 140052 to 141833 | 1/1012 | Replaced by 1/1059 |
| Fuel Tank, Strapped to Cyl Head | 20 to Date | 140052 to Date | 1/1059 | Current |
| Piston with 3 rings only | 10 to 11 | 80000 to 88887 | D13 | 1/1289 |
| Piston with 3 rings and 1 scraper below the gudgeon pin | 11 Only | 88888 to 89599 | D13 | 1/1289 |
| Piston with 3 rings and 1 scraper above the gudgeon pin | 11 Only | 89600 to 91445 | D13 | 1/1289 |
| Piston with 3 rings and 1 scraper below the gudgeon pin | 11 and 12 | 91446 to 96376 | D13 | 1/1289 |
| Piston with 4 rings and 1 scraper below the gudgeon pin | 12 to 13 | 96377 to 112112 | D13 | 1/1289 |
| Piston with 3 rings and 1 scraper below the gudgeon pin | 13 to 28 | 112113 1/31799 | D13 | 1/1289 |
| Piston with 3 rings and 1 scraper below the gudgeon pin | 28 to Date | 1/318000 to Date | 1/1289 | Current |
| Flywheel 12" Crowned | 10 on | 80000 on | D174 | D299 |
| Flywheel 12" Flat 2hp Tank or Hopper Cooled | to Date | to Date | D299 | Current |
| Flywheel 12" with Flat Face Pulley | 10 to 18 | 80000 to 127692 | F174 | F/176 |
| Flywheel 14" with Flat Face Pulley | 10 to 18 | 80000 to 127692 | D372 | 1/682 & 105/229 |
| Flywheel 18" with Coupling Face | 10 to 13 | 80000 to 101364 | D381 | N/A |
| Flywheel 14" with Coupling Face | 13 on | 101365 on | D373 | 1/682 |
| Flywheel 12" with Coupling Face | 10 on | 80000 on | D74 | N/A |
| Flywheel 14" x 3¼" wide | 13 Only | 98000 to 117553 | D374 | For steadier running on700rpm engines |
| Flywheel 14" x 2¾" | 16 to 26 | 117554 to 191770 | D298 | D1238 |
| Flywheel 13" 1½hp Tank or Hopper cooled | 26 to Date | 191771 to Date | D1238 | Current |
| Flywheel with cast-on pulley for flat fan belt | 10 to 18 | 80000 127692 | F174 | F176 12" Dia |
| Flywheel 12" for 2hp 1000rpm | 18 to Date | 127693 to Date | F176 | N/A |
| Flywheel 14" with cast on pulley for flat fan belt | 10 on | 80000 on | D684 | N/A |
| Flywheel 14" for 1½hp 700rpm | 18 to Date | 127693 to Date | 1/682 | For Direct Coupled Lighting Plants |
| Pulley for Flywheel Bolt-On type | 10 to 18 | 80000 to 127692 | 105/229 | When replacing F174 & D372 |
| Pulley for Flywheel Bolt-On V-type | 18 to Date | 127693 to Date | F224 | N/A |
| Silencer 3/4" bore Cast Iron type | 10 to 11 | 80000 to 98999 | D101c | D301c |
| Silencer 3/4" bore Sheet Metal type | up to 13 | 99000 to 101887 | D222c | D301c |
| Silencer 1" bore Sheet Metal type | 13 to 28 | 101888 to 1/46250 | A101c | N/A |
| Silencer 1" bore Sheet Steel type | 28 to Date | 1/46251 to Date | D301c | Current |