(This Retrospective article appeared in the May 2007 issue of Rider.)
New Sports? What was a “New Sports” machine? In this case it seemed to be a “naked” bike partially clothed in a small fairing, which had a curious bicloptic headlight arrangement, the two bulbs side by side.
Definitely unusual. And the engine had two side-by-side cylinders, also unusual. When Yamaha introduced this TDM 850 to the American market for the 1992 model year, the parallel twin design had been out of fashion in the over-500cc category since the collapse of the British motorcycle industry, and Yamaha’s own XS650. A number of midsized twin-cylinder bare bikes, or standards to use the nomenclature of the day, were on the market, some with V-twin engines like the Harley 883 Sportster and the Suzuki VX800, or an opposed twin as in BMW’s 980cc R100R boxer.
By the way, any comparison with a Norton 850 Commando of 15 years previous was purely idle chatter. The only similarity was the inclined parallel cylinders, with the Norton twin being a pushrod, two-valve type, making maybe 45 horsepower, the TDM having two overhead camshafts, 10 valves and some 65 horsepower at the rear wheel. This five-valves-per-cylinder system was part of Yamaha’s self-vaunted “Genesis” design, along with the slanted cylinders, begun in 1987.
The Yamaha company should be commended for bringing out so many interesting models in the 1980s and ’90s, although its American subsidiary tended to be way too cautious about importing some of them to this country. There were monster successes, like the V-Max and the FZ/FZR sportbikes, while others never got imported like the big, superb Super Tenere 750 twin dual-purpose bike that might have given BMW’s GS a run for the money. Others came and went too quickly, and quietly, like the TDM 850.
The marketing mavens at Yamaha USA in Cypress, California, seemed to have some sort of formula involving anticipated sales, and if a new model did not meet these goals within two years, it was dumped. In 1991 the European market received the TDM 850, an all-around motorcycle that could do just about anything well…albeit while a trifle odd-looking. The driving force was that liquid-cooled parallel twin, cylinders inclined forward about 15 degrees.
In Europe the Yamaha folk had been looking at the success of the Super Tenere—not necessarily for racing across the Sahara Desert, but banging through the curvy roads in the Pyrenees or the Alps. Euro types liked long suspension and good cornering clearances, but the very tall seat put many riders off. With European counsel the company decided to bring out a much modified version of the machine, certainly more civilized—if that is the word for a more manageable seat height.
The TDM’s engine was an extension of that powering the Super Tenere, but enlarged to 849cc by virtue of an increased 89.5mm bore, 67.5mm stroke, fed by a pair of 38mm constant velocity carburetors, fuel coming from a 3.9-gallon gas tank. A pair of internal balancing shafts
kept the buzziness down, especially when it was maxing out at more than 7,000 rpm, with the 360-degree crankshaft providing a very smooth torque curve right up to its peak at about 55 lb-ft at 3,500 rpm, and beyond. Great power for urban wandering.
One curiosity was the dry-sump engine, very un-Japanese, with a four-quart holding tank beneath the saddle. All new was the chassis, intended to be more road-going, with the engine serving as a stressed member as it hung from a twin-spar frame, sometimes referred to as a Deltabox. The fork enjoyed mildly hefty 41mm legs, all the better to cope with the occasional pothole, and had preload and rebound adjustments. At the back was a single shock and a box-section swingarm, the shock having preload and rebound adjustments, as well as a quick-change, dual-rate spring arrangement should the rider stop and unexpectedly pick up a passenger along the way.
The front tire was a 110/80-18, the rear, 150/70-17. The twin front discs both had four-piston opposed calipers, the rear, a single disc with a two-piston opposed caliper, so stopping could be effected in a very short time. Wheelbase was a shade over 58 inches, and curb weight around 500 pounds. Seat height was a shade over 31 inches, a lot better than the 35 inches of the Super Tenere. In their promotion of the TDM 850 Yamaha called this a “New Sports” model, trying to create a new niche which combined excellent highway manners and
mild dirt-road pretensions.
To this end the wheel travel was suitably long, with 6.3 inches at the front, 5.5 inches at the back, and since the header pipes were routed beneath the engine a rudimentary bash plate was fitted to protect them, although this was definitely not intended for serious
rock-smacking off-roading. The whole presentation did look a bit strange to the conventional eye. However, the fairing was definitely a plus as it gave good protection to the rider. The saddle was wide and comfortable, both for the helmsman and the passenger, and the highish handlebars provided day-long ergonomics. The suspension and braking were excellent, cornering clearances more than acceptable except for the sidestand tang), and the power was delightful. After five days of commuting, the competent rider could show his twin exhausts to the sporting crowd on weekends, and then trounce off down a dirt road with the passenger aboard for a picnic and a plunge in a hidden swimming hole.
While the Europeans approved of all this, the Americans did not. We were mostly split between cruisers and sportbikes, and the “Tedium” (as some wag acronymously named it) fit in neither category.
Pricing may have had something to do with the lack of sales, as the ’92 TDM went for a hefty $6,600—while an 883 Harley cost only $4,700 and Suzuki’s VX800, $4,900. And Yamaha’s own semisporty four-cylinder Seca II 600 was priced at a measly $3,800.
Yamaha USA gave up on the TDM after two short years, but the model has continued on in Europe to this day. In 2003 the lettering on the fairing was changed to read TDM 900, as the engine was enlarged to 897cc, and ABS was an option.
For 2007, on the European market, BMW priced its liquid-cooled, DOHC, eight-valve F800 parallel twin right at the TDM 900’s MSRP. Imagine that.