The 2012 Triumph Thunderbird - Big Cruiser
The Triumph Thunderbird engine is a 1597cc, fuel-injected, water-cooled parallel twin gives a swept volume of 798.5cc with 103.8mm bore and 94.3mm stroke. The Triumph Thunderbird has the same stroke and 2.2mm more bore than a Triumph Rocket III, but the engine is more than 'just' a Rocket with a cylinder lopped off and spun 90 degree in the frame. Common parts are the eight valves; the rest is pure Triumph Thunderbird.
Getting big numbers, 85 horsepower @ 4850rpm and 146Nm @ 2750rpm, from the engine isn't hard, getting the right character and look is – hence a 270 degree firing interval and twin balancer shafts (plus a torsional balancer) to achieve the right kind of vibes, and an idler gear off the crank driving smaller cam-sprockets to maintain the look of the cylinder head. Belt drive and helical cut six-speed gearbox make less noise (power sapping not an issue).
For the chassis Triumph created a steel tube twin spine with engine as stressed member, 47mm unadjustable Showa forks, preload only rear Showa chromed spring twin shock and similar steering geometry, wheelbase and weight to rival machines aren't the reason the Triumph Thunderbird handles so well – despite a 200-section rear (which on other cruisers tends to make them feel as if the tire is steering the motorcycle), the Metzeler Marathons were developed alongside the Triumph Thunderbird, twin 310mm floating disc brakes front with Nissin 4-piston fixed calipers and rear 310mm fixed disc, with Brembo 2-piston floating caliper stop the Thunderbird well enough, with ABS and optional extra, 22-liter fuel tank gives 322 kilometer range.