Four stroke, parallel
twin cylinder, DOHC, 5 valves per cylinder
Capacity
897 cc / 54.7 cu-in
Bore x Stroke
92 x 67.5 mm
Cooling System
Liquid cooled
Compression Ratio
10.4:1
Lubrication
Dry sump
Oil Capacity
4.7 liters / 0.31 quarts
Induction
Electronic Fuel Injection
Ignition
TCI
Starting
Electric
Max Power
86.2 hp / 63.4kW @
7500 rpm
Max Torque
88.8 Nm / 9.1 kgf-m@
6000 rpm
Clutch
Wet, multiple-disc coil spring
Transmission
6 speed
Final Drive
Chain
Frame
Aluminium, diamond shaped
Front Suspension
Telescopic fork
Front Wheel Travel
150 mm / 5.9 in
Rear Suspension
SwingarmLink-type
Rear Wheel Travel
133 mm / 5.2 in
Front Brakes
2x 298mm discs
Rear Brakes
Single 248mm disc
Front Tyre
120/70 ZR18
Rear Tyre
160/60 ZR17
Trail
114 mm / 4.5 in
Dimensions
Length 2180 mm / 85.8 in
Width 800 mm / 31.5 in
Height 1290 mm / 50.8 in
Wheelbase
1485 mm / 58.5 in
Seat Height
825 mm / 32.5 in
Ground Clearance
160 mm / 6.3 in
Dry Weight
190 kg / 418.9 lbs
Fuel Capacity
20 Litres / 5.2 US gal
Consumption Average
17.8 sec/lit
Standing
¼ Mile
12.2 sec
Top Speed
216.5 km/h / 134.5 mph
Cosmetically similar to the TDM850, the TDM900 is
nevertheless a wheels-up revamp of the earlier bike. Based on the same
design concept as the original, the 900 gave Yamaha a chance to update the
TDM's specification. So while the frame looks similar to the old bike, it is
made of aluminium rather than steel, and the engine uses modern internals,
including ceramic-coated bores, but is broadly similar to the old motor.
Other changes include a new fuel-injection system. From the rider's seat,
the TDM has an updated dash, but the rest of the bike feels similar to the
older machine. The engine offers torquey progress, but is flat compared to
some competing designs. The chassis works well though, and the front brakes
are superb.
First launched in 1991, the TDM850 virtually
created a new sub-category within the street bike market. Powered by a
high-torque parallel twin engine housed in a rigid Deltabox chassis, the
TDM850 has given European motorcyclists an exciting and refreshing
alternative to the ubiquitousin-line four.
With its tractable power characteristics, upright riding position,
comfortable dual seat and avant-garde styling, the versatile TDM850 has
become a favourite choice with those discerning riders looking for a
distinctive all-rounder. From fashionable urban commuter through to mountain
road corner-carver or long-distance tourer, this unique motorcycle is many
things to many people, and its outstanding success has been built on its
unrivalled ability to perform well in many different situations.
Now, a decade after the first TDM850 appeared, Yamaha are about to take this
big twin one step further with the launch of a new-generation TDM900 for the
21st century. Lighter and more powerful than its legendary predecessor, the
new TDM900 delivers even more riding pleasure by offering quicker
acceleration, more agile handling, stronger braking and enhanced cornering
performance, but remains true to the original TDM concept.
The new TDM900's liquid-cooled parallel-twin DOHC 5-valve engine features a
large number of significant changes that not only increase power and torque
output, but also help reduce emissions, improve fuel economy, and further
enhance the bike's already impressive all-round versatility.
Yamaha's designers have also developed a number of new engine components for
the TDM900 that, as well as raising overall performance, also help to reduce
considerably the overall weight of the 2002 machine.
The new engine's bore dimensions are increased to 92mm to give a capacity of
897cc, and the extra 49cc plays a major role in helping to boost maximum
torque by over 11% to 88.8Nm (9.1kgf-m) @ 6,000rpm, while maximum power is up
by over 5% to 63.4kW (86.2HP) @ 7,500rpm.
As well as producing significantly more torque at 6,000rpm, the new TDM900
engine also delivers much higher levels of low to mid-range pulling power
for even stronger all-round versatility.
Complementing the increase in engine size and power output are a number of
new lightweight engine internals. New-design forged pistons offer increased
durability, and run in new ceramic composite plated cylinders that are
lighter and help improve engine cooling. The TDM900 is also equipped with
new carburised connecting rods that are stronger and around 12% lighter, and
the exhaust valve material is modified for improved heat resistance.
Together with the modified 270-degree crankshaft and new lightweight
re-profiled camshafts, these changes deliver enhanced low to mid-range
performance as well as making an important contribution to reducing the
TDM900's weight.
Other detail changes to be found on the new engine include the use of an
R-series type automatic chain tensioner for reduced mechanical noise, and
the fitment of a heavier magneto rotor to give stronger low to mid-range
torque feel.
To help save weight the TDM now runs with a much more compact radiator than
the 2001 model, and this lightweight cooling system is equipped with a new
style 160mm diameter fan.
Another weight-saving feature is the new pressed steel oil tank. Mounted
above the crankcases, this new tank is 23% lighter than the 2001 design, and
is now equipped with an oil level sensor for added convenience.
In order to obtain optimal all-round performance from the more powerful
engine, Yamaha's engineers have equipped the TDM900 with a new 6-speed
transmission and uprated clutch that offer improved shifting characteristics
compared with the TDM850.
The TDM900's 6-speed design uses a slightly lower 1st gear than the TDM850's
5-speed transmission, and runs with closer ratios between 2nd and 6th for
improved all-round performance. With a ratio of 0.923, top gear on the
TDM900 is higher than top gear on the TDM850, and this new 6th gear allows
the new-generation TDM to cruise at lower rpm than its 5-speed predecessor
at any given speed.
To accommodate the new 6-speed transmission the crankcase design has been
slightly modified, while for improved clutch action a new cam-driven clutch
release mechanism is used, and clutch spring preload is increased by 5.6%.
Together with the TDM900's increased torque and horsepower output, this new
6-speed transmission enhances overall performance in a wide range of sports
and touring riding situations, with or without a passenger.
Another important change for 2002 is the use of an all-new Electronic Fuel
Injection system which replaces the twin downdraught carburettors featured
on the TDM850. At the heart of the system is a lightweight resin-encased ECU
that constantly analyses data from a range of sensors relayinginformation on intake and atmospheric pressure, water and intake
temperature, throttle position, exhaust gas emissions, crankshaft position,
cylinder identification, engine rpm and speed.
Using all this information, the ECU calculates the fuel injection period and
injection timing, enabling it to ensure the delivery of the right amount of
fuel for the right duration and at the right time. The Electronic Fuel
Injection ensures efficient engine performance at higher altitudes, while
the increased combustion efficiency reduces the engine's overall fuel
consumption to give an extended range from the 20 litre fuel tank, and for
reliable starting in a variety of conditions the system is equipped with an
automatic choke.
Complementing the Electronic Fuel Injection is an innovative air cleaner
case featuring an adjustable air intake duct and a viscous type filter, and
the TDM900 is the first motorcycle ever to benefit from this sophisticated
new technology. The ECU opens and closes the adjustable intake duct, and
controls the volume of air entering the engine to suit the prevailing
operating conditions.
Featuring a new frame, swingarm, suspension
and bodywork, the TDM900's new high-specification chassis shares very little
in common with the 2001 model, and as well as being significantly lighter it
also offers enhanced handling performance.
One of the most significant changes on the TDM900 is the all-new aluminium
frame which replaces the previous model's steel design. Featuring
widely-spaced twin spars and a detachable sub frame, this new frame is 29%
lighter than its predecessor, and at the same time offers much greater
torsional, vertical and horizontal rigidity.
New-design brackets are located below the frame's main spars, and these are
equipped with R-series type rigid engine mounts that attach to the cylinder
head for increased chassis stiffness. Also new is an aluminium box-section
swingarm that offers lower unsprung weight and higher rigidity for improved
suspension action.
To match the higher-specification chassis the TDM900 is equipped with
uprated 43mm front forks. For 2002 they feature adjustable rebound damping,
and also a preload adjustment facility. Offering a generous 150mm of wheel
movement, they can be quickly and easily adjusted to suit different riding
situations.
The totally new rear end features a sophisticated link-type suspension and a
piggy-back shock absorber that is equipped with adjusters for rebound and
compression damping as well as for spring preload. The linkage system gives
rising rate suspension characteristics for better performance, and the
fully-adjustable shock enables the TDM900 rider to choose the best set-up.
Every effort has been made to reduce weight
where possible, and the TDM runs with new-design 3-spoke wheels that are
lighter and also wider. The MT3.5 front wheel is fitted with a wider
120/70-ZR18 tyre, while the MT5.0 rear wheel carries a fatter 160/60-ZR17,
and this combination of lower unsprung weight and wider front and rear tyres
makes for improved road holding and smoother suspension action.
Just like virtually every other chassis component, the braking has also been
uprated, and the TDM900 is fitted with new R1- type one-piece 4-piston dual
calipers at the front end that slow a pair of 298mm diameter floating discs
manufactured from 5mm thick steel, 1mm up on the 2001 model. Together with
the new pin-slide type rear caliper, this new braking system generates
strong and progressive stopping performance and offers plenty of feel.
For added convenience the front brake lever
features a 5-position adjuster, while both the rear brake lever and gear
change lever are now manufactured from forged aluminium to save weight ¨C
and for reduced friction the gearchange shift rod layout is changed.
Yamaha's designers have created all-new bodywork for the TDM900 that gives
the machine a much more dynamic and stylish feel, and at the same time is
instantly recognisable as being a TDM.
The new more angular and aggressive-looking cowling flows seamlessly into a
new-look 20-litre fuel tank, and the cuttingedge
styling is complemented by new dual multi-reflector headlights and
redesigned tail light. Completing the package is a new front fender,
restyled tail and comfortable new dual seat.
Source mcnews.com.au
Any corrections or more information on these motorcycles will be kindly appreciated.