Suzuki GT series

Alternators featured a three-phase excited field type using brushes and slip rings with a wound rotor.

Previously Suzuki had primarily used a permanent-magnet single-phase alternator setup on its bikes so the new equipment was quite a step up for the GT series.

[1] This system consisted of a cast aluminum shroud covering a modified cylinder head to direct the cooling air.

Suzuki thus led the motorcycle world by being the first company to mass-produce a liquid-cooled, large-bore two-stroke engine.

[citation needed] The 550 initially featured chrome-plated piston rings and cast iron cylinder bores.

The coating, marketed as Suzuki Composite Electro-chemical Material or SCEM, is nickel-phosphorus-silicon-carbide based, reducing weight (by eliminating a steel liner) and improving heat transfer, allowing for tighter and more efficient piston-to-cylinder clearance.

[citation needed] Frames were all-welded mild steel tubing with long wheelbases to give stability at high speed.

For the 1973 MY, the T250 twin was updated with new bodywork, Ram Air cooling, a single disc brake in front and was now designated GT250.

The GT250 retained its original engine and six-speed transmission, both remaining basically unchanged from the T20 X6 Hustler of 1966 through the T250 model to the 1972 MY.

The rubber stopper for the transmission oil fill hole allowed the dip stick to vibrate enough to contact the primary drive gear.

This model was similar in layout to the GT185 but with a shorter wheelbase and smaller engine displacement so shared only a few common parts.

The electric starter was deleted, probably in the interests of economy, which allowed a more attractive selling price in the very competitive "beginner" market that this model competed in.

The GT500 was not graced with Ram Air cooling, probably because Suzuki already knew that their large-capacity two-stroke road bikes were reaching the end of their production lives.

Both the TR750 and TR500 models were famously campaigned by Barry Sheene who became inaugural F750 champion in 1973 and in 500 cc Grand Prix racing with factory-supported development-rider Jack Findlay.