For the most part American and Canadian bikes were built to the general export specification E1 with one very notable exception - North American M, A and B models came with 'L' model engines and exhausts through till the end of production. The SCEM engines sold elsewhere globally with the plated bores, additional ports and iron rings, together with the updated exhaust systems (no cross overs) and carburation were not offered.
Suzuki in North American used names for advertising their triples - the GT550 was called 'Indy' after the USA race track.
Other minor differences included:
Stand-off brackets were installed to extend the rear turn signals out further (41650-33001 and 41650-33001). The signal units themselves were the same as per the E1 specification, having part numbers 35601-31010-999 for the front, and 35600-31830-999 for the rear.
Front signal lenses for all models were amber/orange, rear signal lenses for the 'J', 'K' and 'L' models were red (35652-31610), changing to orange in 1975 with the 'M' model through till the end of production.
The front side marker reflectors were amber in all years and the rear were red for the 'J', 'K', 'L', 'M' and 'A' models.
For 1977, as in most countrys the GT550 had the new 'GS' style rear tail light. The North American tail light lens incorporated red side reflectors and is 35712-45010.
Reflectors were mounted on a chromed plastic backing till part way through the 'A' model year when the backing changed to grey (no chrome) for the remainder of the 'A' and for the 'B' production.
The alternator, regulator and points normally fitted for most model years seems to have been the Nippon Denso unit, but some Kokusan units were fitted - at the moment the use of Kokusan components seems to be rare.
North American models were fitted with a front brake light switch as standard from 1973 'K' onward.
Springs were fitted to the exhausts from late 'L' models onwards till the end of production to try and help minimise exhaust gas leakage through the cross couplers.
E3/E28 specification switch gear differed from the general export E1 version, principally in not having a 'pass' or 'flash' button on the left switch gear. The 'J' part numbers were 57700-33010 for the left, and on the right side, 57100-34010 whiuch was the same as was used for the E1 General Export models.
In 1973 the right side handlebar switch gear was the same as was used in 1972, and the left side switch gear looked the same but was part number 57700-33011.
For 1974, the right side handlebar switch gear was updated and rounder, and also was now the same part number in all markets globally (57100-34012).
The left side switch gear was similar to that used in 1973 as in 1973 the turn signal switch actuator has a half round head, and is secured from the underside to the switch plate by a screw. The markings on the switch gear are changed from 1973 in that the arrows showing left and right for the turn signals now had the word 'TURN' marked beside them. As well 'HORN' was spelled out and the 'H' and 'L' high low dipping switch for the headlamp now was marked as being 'Lights'. The part number was 57700-31602.
For the 1974 L model, the Stardust Silver Metallic (Suzuki paint code 737) offered elsewhere in the world was not available in North America
For the 1974 L model, the green offered in Canada/US was called 'Hawaii Green', but is the same 'Candy Turquoise' under Suzuki paint code 215 as offered elsewhere.
Likewise, for the 1974 L model, the red offered in Canada/US was called 'Laredo Red', but is the same 'Marble Scarlet' under Suzuki paint code 293 as offered elsewhere.
For 1975, the right side handlebar switch gear was basically the same as used in 1974, but the left side switch gear turn signal switch head was changed and now fused to a switch arm that extended into the switch housing. Rather than being a rounded shape, it was now rectangular. The markings on the switch gear were updated again - the arrows were gone, and an 'L' and an 'R' were added. The part number was 57700-31603.
For the 1975 M model, Candy Orange-2 (Suzuki paint code 00Z with black trim lines on the tank) offered elsewhere was not offered in the NA market.
For the 1976 A model, the NA market was offered 'Forest Green' (00X} - Black was not offered
A 'headlamps always on' feature was added in the USA and Canada at frame GT550-56555. It was fully implemented for the 1977 model year (new switch part number 57700-31622). The function was provided by adding the tab indicated by the arrow to the on/off slider to prevent it moving.
Rear grab rails were optional for the 'A' and 'B' in Canada and the USA.
Three different headstock labels were used in the USA - these photos are all of GT750's, but the other GT models were essentially the same:
a metal plate riveted to the headstock and similar to the style used elsewhere globally in 1972 (Canadian shown on the left, but it was the same as used in the USA)
a rectangular foil label, narrow in width in 1973 (shown centre)
a rectangular foil label, narrow in height which was applied vertically on the headstock and used from 1974 onwards (shown on the right).
In all cases, in the USA and Canada only the frame number was recorded for registration purposes.
Most on line parts fiches show the E3 parts listings, and so I have not included E3 specific ones here. They are available at multiple web sites, including my own eventually at this link.
