Friday, September 26, 2014

How to find the model year of Indian Royal Enfield Bullets

How can you determine the model year of an early made-in-India Royal Enfield Bullet? It's probably the most common question I'm asked and it's very hard for me to answer.

But here's help.

The chart below is the work of the Royal Enfield enthusiast who signs himself "Tim N.Z." on Royal Enfield message boards across the Internet.

Tim posted his chart on the Bulletech Yahoo Group, an online forum with many Indian members, who, of course, are most likely to be the ones with questions about their motorcycles.

Enthusiasts around the world should be grateful as well.

Collectors, whether in India or elsewhere, place a higher value on the made-in-England Royal Enfields, and on those early Indian-made Bullets that at least included British made parts.

As Royal Enfield in Redditch, England wound down in the 1960s there was less and less of this and, eventually, Bullets were made completely in India.

Many thousands of these purely Indian Bullets exist and the temptation to restore them as counterfeit British motorcycles naturally exists as well.

Cosmetic items are easily changed and motor and frame numbers can be altered. Old looking (but cosmetically restored) Royal Enfield Bullets often appear on eBay and CraigsList in the U.S. identified as genuine British motorcycles. Asking prices for these are very high.

Tim's chart is intended to look beyond outward appearance and motor and frame numbers. He withheld some of what he knows rather than tip off counterfeiters.

"I hope it may be of use for you, and also to others, to help with the positive identification of the older Indian made Bullets," he wrote me.

(Note: years noted are model years, and are not necessarily calendar years.)

June 1956 G2 37XXX last fully complete English-assembled Completely Knocked Down (CKD) bike is shipped to Madras. EI numbering sequence commences with G2 37XXX EI 5XXX. Ignition by SR1 magneto and 6-volt "hex" alternator, replacing former mag/dyno.

Indian made Type 1 modified frame construction commences on tooling supplied by Redditch factory. It's a simplified version of the English made frame no longer using the cast frame fork-head; instead frame was made from all tubular metal, and welded. CKD motorcycles sent to Madras no longer include a British made frame. Mudguards and tool boxes now also produced in India.

From 1956-'62 the Indian Bullets used the locally made frame (Indian Type 1) with curved loops that connected the lower seat tube to the swingarm bracing gussets.
Introduction of points ignition; coil located inside right hand tool box.

1962 (late)
Type 2 frame production commences. Modified rear frame loops to the lower saddle tube, now straight and bolted up through lower end of saddle tube. Entailed use of longer top gearbox mounting plates. (This is the same construction style as latest frames).

From 1962 onwards the Indian frame was further modified to the form (Indian Type 2) we still see today: Straight tubes up from the swingarm gusset plates, with the long through bolt above the gear box, and extended top rear gearbox mounting brackets. Note the absence of the forward solo seat mount? The front solo-seat mount is a feature that was later reinstated.
1964 (April)
Last English made CKD bikes supplied to India. All frames now the Type 2 (Indian) manufacture. All bikes are now fully built in India from local and imported components

Indian made crankcase commences from engine number G2 66XXX EI XXXXX. Addition of crankcase number (actual Indian crankcase number) added underneath the engine breather boss on drive side of crankcase. This additional number has a constant difference factor relative to the G2 and EI sequence numbers

1968/9 (circa)
G2 numbering sequence changed, B prefix introduced, along with a number/letter suffix denoting year/month. EI Numbers continued along crankcase side.

Wheel bearings changed from Imperial to metric (6203) from engine number B 113545 2JX.

X suffix added to crankcase engine number. Denotes the change over from Imperial to metric bearings and the replacing of the former built-up timing side roller bearings with a caged roller bearing. Deletion of oil return pressure relief valve. All return oil now passes over cylinder head.

EI numbering sequence ends.

Last English made part (con rod) supplied to Madras. Henceforth bike is completely indigenous manufacture.

350 Bullets imported into UK. Half-width hubs front and rear wheels, 6-inch single leading shoe brakes, Villiers carb, "one key fits all" ignition lock mounted in right hand tool box. 6-volt electrics, with emergency start provision to run directly off alternator. Pressed mudguards of deep section. All bikes painted red. Dual seat standard.

Ignition coil mounting moved to the fixed section of the rear mudguard from inside the toolbox. May, 1980 alternator stator previously fitted onto an adaptor ring now attached direct to chaincase.

Fulcrum lever added to the center stand makes the center stand easier to use. Center stand  previously retained by two nuts now retained by split pins and washer. Oil pump covers changed to Pressure Die Cast and reinforced with ribbing to increase their strength. Rear wheel changed to quick detachable (QD) type with the sprocket fixed to the swingarm. Early models had a small rear hub to which the sprocket was attached on one side and the speedo drive attached on the other side. X suffix dropped from engine number. Speedo hub drive shifted to the front wheel to allow for the new QD rear wheel. New rear shock absorbers with adjustable spring rating (previously non-adjustable). A German designed Bing carburetor giving improved fuel efficiency replaces the Villiers carburetor. 19,512 motorcycles produced.

Crankcases are paired and in-line bored (timing side and drive side crankcases are bolted together then the bearing holes are made in one operation). This avoids offset bearing bores and eliminates main bearings failure. Engine/frame number gains a number prefix denoting year of manufacture. Petrol tank filler hole enlarged and a larger round filler cap introduced. Front fork with integral oil seals replaces earlier screw type seals. Pressed steel handlebar levers with curved ends. New combined dip switch/horn unit with plastic horn button replaces metal button, which sometimes shorted in wet conditions. Deep rolled front mudguard replaces flat-sided pressed mudguard. Bike lifting handle fitted to drive side. Winged petrol tank badge has ENFIELD (previously ENFIELD INDIA). Individual ignition keys introduced for the ignition unit on the timing side toolbox (previously a one-key-fits-all unit was used). Black plastic ENFIELD cover for the contact breaker unit (previously a painted metal cover). 222,225 motorcycles produced.

Four-plate rectifier replaces eight-plate rectifier. Finned, chrome-plated tappet chest cover replaces plain alloy cover. Front brake and clutch levers chrome plated (previously black).

Trafficators (turn signals) introduced. These work with the bike's 6-volt electrics.

Twelve-volt electrics introduced  (previously 6 volts).

Mikarb carburettor introduced, replaces Bing carburetor. Long silencer fitted to new export 500ce Bullets now also fitted to 350cc export bikes.

New export-only 500cc Bullet released. Long silencer fitted to all export bikes. (Note: very few 500s were made in 1988.)

Low rider/high pillion dual seat introduced on export models. Domestic models retain the early flat dual seat.

Oil pump cover screws changed to metric (previously Whitworth). Engine/frame number gain a letter suffix denoting month of manufacture.

Horn location changed to front facing from side facing. Five-ampere battery replaces 5.5-ampere battery and battery top cover changed to Fiber Reinforced Plastic on 500cc Bullets.

Folding kickstart crank introduced (previously a fixed type used). Rubber guides introduced on front mudguard to route the speedo and front brake cables (?) to avoid cables fouling the mudguard. High beam and turn signal indicators relocated inside the speedometer (previously positioned in the casquette facia). Cylinder head valve guide and valve seat housing now inline bored. 325cc diesel introduced in November.

Twin leading-shoe front brake introduced on domestic Bullets. Ignition key moved to casquette from right-hand toolbox. Headlamp switch moved from casquette to left handlebar electrics cluster. Left-foot gear change for the U.S. market.

Lockable toolboxes fitted (Coke-bottle-top shaped fasteners formerly employed). Front fork triple-lip oil seal introduced (previously a double-lip seal). Rectifier and regulator become two separate units (previously a one-piece unit (?). Neoprene seal fitted to big end oil pump worm nut (replaces cork oil seal). Three-piece clutch rod introduced (formerly a two-piece rod was used). Clutch center and plates redesigned. Note: you must use old shape center with old shape plates and new center with new shaped plates. A mounting strip is incorporated into the frame for the rectifier/regulator/flasher unit positioned underneath the dual seat. Common key introduced for the ignition switch, toolbox locks, petrol tank and steering lock. Valve guide material changed from phosphor bronze to cast iron for improved life . Lightning model introduced in 350, 500 and 535cc. Many internal changes for the 535cc engine: larger piston, and oil pumps being the most noticeable.

Rocker bearings with double pins and ground stud locators introduced (replaces early free-floating bearings). Pulse Air Valve (PAV) emissions control system introduced on all export and domestic 500cc Bullets except for U.S. models. Silencer bracket becomes separate (previously welded to the silencer). Electrics changed from DC to AC/DC in 350cc Deluxe models for improved reliability and brighter headlamps. 21,621 motorcycles produced.

Warranty on domestic Bullets brought in line with export machines: one year or 10,000 km previously six months and 8,000 km. Larger 28-notch rear chain adjusters introduced (previously 23 notches). Royal Enfield motifs introduced on export model petrol tanks replacing Enfield logo.

Air filter moved from air filter box to right-hand side toolbox on export models. Crankcase breather diverted into a breather oil collection box and recycled into crankcase on export models (previously sprayed oil onto rear chain). Silencer baffling increased to meet future noise emissions legislation. Push-pull type choke knob introduced on 350cc carburetors for ease of operation. Electrical connections changed to coupler connections from bullet connectors for better connectivity. Bonded brake shoes introduced on the rear brake (previously riveted). Shielded ball bearings fitted in front and rear wheels replace traditional unshielded ball bearings for improved life. One pair of additional friction and metal clutch plates fitted to the 350cc clutch for better transmission of power.

Round turn signals introduced (previously rectangular on domestic bikes; the front ones attached directly to the casquette, center line with the head lamp). Electrics changed from DC to AC/DC on all models for improved reliability and brighter headlamps. Royal Enfield logo on all rubber parts, i.e, foot pegs, kickstarter rubber, gear lever rubber etc. (previously Enfield). A 350 Machismo released. All new motor designed by AVL in Austria, with new barrel and head, CDI ignition, new crankshaft with steel con-rod and roller big end bearing, gear oil pumps inside new timing cover. Revised cam lubrication; camshafts no longer flooded. Internal drillings drain timing cover oil to return oil pump then back to oil tank. CV carb, optional disc front brake.

Push rod adjusters changed to metric (previously Whitworth). Oil seal fitted to timing-side of 350cc crankcase where the timing shaft comes out, to reduce wet sumping. Crankcase and chaincase fasteners become metric (previously Whitworth). Foot peg rubbers design changed to ring groove pattern

Rolled front and rear mudguards are fitted to domestic 350 Bullets (replaces pressed guards). Duck bill type centrally mounted side-stand introduced on domestic models (replaces rear-mounted side-stand). Final drive sprocket nut fitted with a neoprene seal to prevent grease escaping from the gearbox (replaces felt seal). Long silencer introduced for domestic models. Air filter moved from air filter box to toolbox on domestic models. Crankcase breather diverted into a breather oil collection box and recycled into crankcase on domestic models (previously sprayed oil onto rear chain).
New type integral steering lock introduced. October 2001, electric start available for export models.

Chromed cover for contact breaker points introduced replaces black plastic cover. Electronic Ignition (CDI) introduced on domestic Bullet 350cc. Five-speed left foot change gear-box available on domestic bikes. Hex headed metric sized bolts used to fasten the engine to the frame at the front replaces studs and nuts. Oil pressure relief valve fitted in the timing shaft and increased volume oil pumps fitted to 350cc Bullets up-rate the 350cc bike to 500cc Bullet specifications. Pillion footrests become foldable on 350cc domestic Bullets. Royal Enfield motifs used on domestic model petrol tanks replace Enfield logo. Engine and clutch fastening studs and nuts changed to metric from Whitworth. O-ring rear chain introduced for domestic bikes for increased chain and sprocket life. Optional disc brake available on Electra

Rubber shield bearings used in both wheels increase longevity. Handlebar vibration dampener introduced on domestic Bullets to reduce rider fatigue. Flanged bolts and nuts used on frame mountings. Front brake cam modified and new brakes shoes fitted. Throttle cable modified. Modified clutch assembly introduced. TCI ignition introduced on 350 Electra. Improved valve seats (hardened) fitted to all Bullets. Stellited exhaust valve fitted. Mudguard mounting screws changed to stainless steel. Heavier fly-wheels fitted to 350cc – same weight as 500.

New Sixty-5 model released. Features electric start mounted to the lower front of the cylinder barrel, and driven through a sprag bearing and an idler gear to the crankshaft, five-speed left-foot gear box, revised air-filter and tool boxes, gaiters fitted to front fork stanchions. New twin seat, with revised padding and covering. All new primary cover, inner and outer to incorporate electric start.
Available in purple, red, silver or black. Chrome springs on rear shocks, revised shock absorber top covers (shorter).
AVL engine Machismo 350, new single seat and pillion pad, flat-sided tool boxes.
Prototype Electra-X first shown. Similar to the domestic market AVL 350: New barrel and head incorporates rockers, new crankshaft with steel con rod and roller big end bearing. New timing cover with gear oil pumps. Decompressor deleted, and a valve lifter fitted instead (operates via exhaust pushrod off the tappet inspection cover). Gas shock absorbers, disc brake standard, New front mud guard. All new air-filter assembly and tool boxes. Features the new electric start.
Rear guard stays deleted, revised rear guard, CV carburetor, handlebar switch gear upgraded. New modern alternator and voltage control.
All Bullets now fitted with revised cam pinions to match those fitted in the Electra (smaller diameter ends). Domestic bikes have new frame with revised pillion foot peg mounts. Revised engine breathers, now off top of oil tank. Engine oil dip stick changed to screw-in type from press-lock bayonet fitting. In conjunction with changed crankcase breathing, engine now breathes through top of oil tank and altered fume catch can with oil drain back into timing cover.


  1. My 1994 military has tls front brake, lockable tool boxes, and lights in the casquette facia, not the speedo.
    I think the Indian army had it for 3-4 years, then the factory refurbished it in 1998, before it was imported into the UK.

  2. Nice article. Found my own Picture at the top ( first frame pic With curved loops ) and that was fun and completely all right. My bike is now almiost finished from beeing rebuilt in a completely different style. Done som chopping to it and got a real low style.

  3. My frame doesn't have the solo front seat mount so it must be a 1962

  4. "Deletion of oil return pressure relief valve"
    Oil return pressure relief valve was continued till 1974 and discontinued sometime later in 1974 and not in 1973.

  5. It'a very useful information for enfield enthusiasists. Now a days vintage enfield are not fitted with original spares.. with this article we can easily find the model and what is fitted..

  6. A very good article..

  7. What about 2008/9 CI model

  8. 53334/x
    Which year and which model?
    Kindly inform me or whatsapp me plz.7894761623

    1. Not an expert on that but an expert does exist. Email Graham Scarth, chairman of the Royal Enfield Owners Club UK at and be sure to include all the numbers you can find on the motor, left side of the headstock facing forward, and the gearbox, along with a description of the motorcycle and its origin, as best it is known. He welcomes photos. He does not charge for his services. Good luck.


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