Royal Enfield launched its new bike the Thunderbird Twinspark in 2008. But it was under some serious scrutiny by Bajaj Auto Ltd because of the name and the twin spark technology. Bajaj patents the twin spark technology and it had previously filed a suit against TVS motors for the same reason. But according to Royal Enfield they have not breached the patent copyrights as it holds good for 75 and 250 cc engine bikes whereas the Thunderbird is of a 350 cc version and they plan to incorporate the same technology in their future series of bikes too.
Design & Engineering :
A first look, and you would be hardly able to tell the difference between the Twinspark and any other Thunderbird, till you see the engine. It’s a contemporary looking powerplant with an incorporated crankcase and gearbox projected to lessen oil seepage. Every other bit is similar; the round headlamp, double instrument pods, front disc brake, seat and pillion backrest are all the same as the normal. Thunderbird’s. A notable visual difference is the shorter muffler that we received on our test bike.
The panels underneath the seat feature a minuscule ‘Twinspark’ sticker, which is the lone sign of this key technical step forward of the bike. Also on either side, just beneath the tank, are round reflectors; a helpful touch when you’re emerging from a side road onto a highway.
The fuel tank is sheet-metal, and the overhang welded below it is a blemish, while the fuel tank cap looks dated. The Twinspark does well to offer slow- cam chain adjusters, as compared to the more predictable system provided on most Indian models.
Paint and fit-finish is still is not upto the mark.
Drivetrain & Performance :
The all-new engine has twin-spark plugs, an automatic decompression facility and unit-construction that the company claims has answered the crisis of oil discharge, a key problem with the old engine. Although a lot does stay alike, other important changes contain a high-flow trichoidal oil pump, hydraulic tappets, an automatic primary chain tensioner and the drive chain assembly shifted to the right side in order to reduce transmission loss.
The Twinspark benefits from TCI ignition for a fine spark. You get 2bhp more, for a figure of 19.8bhp, and 2.85kgm of torque, which is a insignificant 0.1kgm more than the older version.
Start it and you instantly notice a smoother feel near idle. The handlebars don’t judder in your hands just yet. Select first gear and as you let the clutch out, it feels a bit improved. A six-plate clutch instead of four makes the difference. As you hasten through the gears, this smoothness unfortunately diminishes however, to be replaced with Royal Enfield characteristic vibrations, Which is where it goes from bad to worse, and it’s apparent that thrashing the engine is not the way to ride this bike.
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