Yamaha 850SS, anyone?
SINCE THE arrival of thetdm850 in 1991 there had long been speculation about the creation of a sportsbike with the same twin cylinder engine. But it took the creation of a one-off special to spuryamaha into action.
The ‘850 Super Twin’ was created by leading German magazine Motorrad and was essentially an FZR600 fitted with ATDM850 engine from parts donated byyamaha themselves.the factory then confirmed its interest by taking the bike to its European base inamsterdam for further evaluation.
After this, in the autumn of 1994, rumours of an official sports TDM850 began to gather serious pace, especially when a prototype mule was spotted undergoing testing in the south of France.
Even so, when first launched in 1995 the TRX850 was never intended as a European model, and was first sold only in Japan.
On face value it was a blissfully simple idea: takeyamaha’s performance twin engine, bolt it into a semi-sporting road chassis with lots of cost cutting via raiding the parts-bin and voila – a ‘Yamaha 850SS’.
In realityyamaha got a lot closer to the Italian than that rather simplistic approach sounds, courtesy of two variations. Firstly, rather than use its own trademark ‘Deltabox’ twin-spar aluminium frame (as the Germans had done with the Super Twin),yamaha’s engineers pretty much copied the tubular steel trellis-type frame which had become a Ducati trademark.the result, at first glance at least, left no one in any doubt about which machine the new Yamaha was aspiring to beat.
Second, and probably more importantly still, thetrx’s five-valve, parallel-twin motor wasn’t ‘just’ that of the TDM850. Instead, it had been significantly and cleverly reworked with a new 270º crankshaft (in place of the TDM’S 180º) to give a lumpier sound and feel more akin to that of av-twin – a practice that’s widely copied today.
The result was impressively effective: twist the throttle of theyamaha and you’d be forgiven for thinking you were aboard a Ducati SS shuddering through its characteristic rough spot between 3-5000rpm.above that, a balancer shaft smoothed out vibrations as the Japanese twin fired up to its 8000rpm redline. Elsewhere, however, thetrx’s design was more