1964 TRIUMPH TR6 BY THE NUMBERS
While model years 1962 & 1963 saw only one model designation for all Triumph TR6s, the Triumph TR6S/S, 1964 saw a plethora of TR6 engine prefixes: TR6SS, TR6R, TR6C, TR6SC & TR6SR, and goes to show how the TR6 & Bonneville families had virtually taken over the Triumph lineup, in place of the stodgy 6T Thunderbird & the now-redundant T110 Tiger. Engine & Frame Numbers for the 1964 Triumph TR6 ran from DU6127 to DU13287, built from August 29, 1963 to August 5, 1964.
MINOR ENGINE CHANGES & IMPROVEMENTS
Just a year earlier, the entire 650 twin line was almost completely re-engineered, with a new unitized (unit-construction) engine & a whole new frame, among other things. And changes made at this point would have been purely developmental, solving toothing problems with all the new components. The engine breather was extended all the way out to the rearmost extreme of the bike. The Amal Monobloc carburetor was increased in size to 1-1/8″ with all new jetting. The kickstart shaft got a seal to stem oil seepage. The “C” models (“C” stood for Competition, these were off-road race bikes) got modified engine sprockets allowing more accurate ignition timing, crucial for the Energy Transfer ignition system (run on alternator power alone, without a battery).
FRAME & CYCLE PARTS SLOWLY IMPROVE
Triumph Motorcycles had always made steady, incremental improvements to its products & the 1964 Triumph TR6 was no exception. Footrests were now attached to the rear engine mounting plates to improve ground clearance. A new front fork was introduced with external springs & rubber gaiters. The new 6-pint oil tank was rubber mounted with a left side cover to match. New Smiths magnetic anti-vibration gauges (speedo & tach) were added. Speedometer #SSM5 001/00 replaced #SC 5301/09; and tachometer #RSM 3001/02 replaced RC 1307/01 on all bikes equipped with gauges.