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Comparison of the Yamaha WR 450 F against the WR 450 F 2-Trac

Push and pull

Adventurous handicrafts, bizarre prototypes, high-tech test vehicles, hand-made one-offs: there were plenty of experiments, commitment and pioneering achievements. Well has Yamaha that
first all-wheel drive series motorcycle brought onto the market, without any restrictions
should be suitable for everyday use. The principle developed by the Yamaha subsidiary Ohlins was already presented in detail in MOTORRAD 25/2003. An additional pinion and chain drive a hydraulic motor at the gearbox output. It pumps oil via flexible lines to the oil motor in the front wheel hub. The hydraulic ratio is chosen so that the front wheel transfers almost no drive torque when rolling on hard ground. Only when the rear wheel slips is part of the drive power for the front wheel increasingly diverted. In extreme cases up to
30 percent, however, is the maximum
Drive power limited at the front by a pressure relief valve.
MOTORRAD was able to convince itself of the advantages of all-wheel drive in a comparison with the standard WR in a former coal mining area near the French city of Belfort. In contrast to all previous concepts, the disadvantages are limited. At first you hardly notice the additional drive,
the steering properties are only minimally affected. The higher weight of the front wheel unit, which the fork has to contend with over brake shafts, is only noticeable when driving at a faster pace. With small jumps, the 2-Trac seems more top-heavy and sluggish, not least because of the approximately seven kilos higher weight. But you can and may do everything with her that any real sports enduro should do.
The handling is only slightly worse on grippy terrain. A look at the stopwatch reveals that the front-wheel drive slows down because of further arcs, but the bottom line is that it costs little time. So much is clear: Anyone who drives in the special test for time in enduro sport has a small handicap, but that doesn’t mean that they have no chance.
The additional drive can only show its advantages under adverse conditions. So in deep mud, soft sand or on extremely slippery surfaces. How serious the difference is in unprovoked desert sand was already evident from the
first contact as part of the Shamrock rally in Mauritania. The 2-Trac is more stable and on fast sand slopes
moves cleanly in curves, while
With the conventional machine, the front wheel bores deep into the ground. Whereby the front wheel of the 2-Trac doesn’t pull large sand fountains behind it. However, if you look closely you can see that it sinks less deeply into the ground, which reduces the resistance. Even starting on the dune slope is possible without any problems. In contrast, the single-wheel WR does not make any progress without pushing.
MOTORRAD experienced further advantages on the coal dump. For example, that the 2-Trac pulls better even when hill climbing, where almost the entire weight is on the rear wheel. The trick is to put pressure on the front wheel ?? unlike the normal WR, in which the rear wheel needs the entire weight if possible. The 2-Trac also accelerates better on very slippery ground. But only if the rear wheel is spinning heavily. Only then is there noticeable torque transmitted to the front wheel. Incidentally, the driver does not feel the transition, the front drive begins softly and unspectacularly.
The 2-Trac costs 12,350 euros, 7895
the standard inverter. For the sizeable
Difference of 4455 euros there is a complete Ohlins suspension plus steering damper. And maybe the 2-Trac will soon have competition, KTM also has two-wheel drive in the pipeline. gt

Technical specifications

Engine: water-cooled single-cylinder four-stroke engine, two overhead, chain-driven camshafts, five valves, flat slide carburetor, Ø 39, five-speed gearbox, rear wheel drive via chain, front wheel drive hydromechanical.
Bore x stroke 95 x 63.4 mm
Displacement 449 cm3
Compression ratio 12.5: 1

rated capacity
38.6 kW (53 PS) at 9000 rpm
eligible:
30 kW (41 hp) at 8500 rpm

Max. Torque 49 Nm at 7500 rpm
Permissible: 36 Nm at 6500 rpm

Chassis: steel single-loop frame, upside-down fork, Ø 46 mm, central spring strut with lever system, front disc brake, Ø 250 mm, double-piston floating caliper, rear disc brake, Ø 245 mm, single-piston floating caliper.

Tires 90 / 90-21; 130 / 90-18

Dimensions and weights: wheelbase 1485 mm, seat height * 980 mm, empty weight * 128 kg, tank capacity 10 liters.

Warranty three months

Colors blue

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