UP FOR SALE IS A COMPLETLY RESTORED TT500 YAMAHA IN STUNNING CONDITION.
1977 MODEL, ALLOY COMPETITION TANK, MAGNESIUM BRAKE HUBS ETC. ETC. ETC.
MOT till December 19th 2012 and TAX Till end of November

Model Yamaha TT 500
Year 1975
Engine Air cooled, four stroke, single cylinder,
Capacity 499
Bore x Stroke 87 х 84 mm
Compression Ratio 9.0;1
Induction 34mm Mikuni
Starting kick
Max Torque 27 ft-lb @ 6000 rpm
Transmission / Drive 5 Speed / chain
Gear Ratio 1st 20.97 / 2nd 13.84 / 3rd 10.59 / 4th8.15 / 6th 6.92
Front Suspension Telescopic fork
Rear Suspension Swinging arm
Front Brakes Drum
Rear Brakes Drum
Front Tyre 3.00-21
Rear Tyre 4.60-18
Seat Height 33.2 in
Dry-Weight 282 lb
Fuel Capacity 2.24 gal

Yamaha was watching closely from the sidelines. No doubt the thought of reviving the thumper crossed their minds, but why risk it? Let Honda do the investigating research, development and marketing. Then, if Honda succeeded, move in with a model that would one-up the XLs. That's where the TT500 comes in. To be produced in both street-legal Enduro (XT), and play bike (TT), configurations, the new 500 ohc four-stroke from Yamaha is a tremendously versatile and appealing machine.

The engine is a straight-forward two-valve Single. Bore and stroke measure 87mm x 84mm, yielding a total displacement of 499cc. The overhead cam is run by a chain off a sprocket on the right side of the motor. Chain pitch is identical to that used on the Yamaha 650 Twin. Tension is maintained by a rubbing-block tensioner that is easily adjusted from outside the engine. The camshaft itself is supported on both ends by ball bearings.

Delivering the engine's power to the five-speed transmission are a set of straight-cut primary gears. Normally, straight-cut primaries exude a loud whine. But the ones on the Yamaha were absolutely silent.


The TT500 can scare you in other ways though. The exhaust system makes the bike so quiet that you find yourself entering fireroad corners way over your head. You don't realize how fast you're going. This system is designed to pass the 86-db limit. The one on the XT Enduro model is expected to put out a mere 81 db. You could pull wheelies in the church parking lot during High Mass and no one would know you were there.

Air intake is high and to the rear of the bike. Impurities are filtered out by a washable foam element. Crankcase pressure is vented through a PCV valve. Any oil that might be pushed through the valve is trapped by a cone-shaped plastic stopper and returned to the engine once it is shut off. Vapors are directed through a hose and back to the intake tract.

Suspension is both old and new. The front forks are identical in appearance to what Yamaha has been producing these last few years. They also perform identically. That is to say, poorly. Not only do the forks pogo excessively, but they exhibit flexing traits at the triple clamps that make stability at speed in rough terrain mildly sketchy. The flexing you'll have to learn to live with if you're a banzai-type rider. The poor fork action will hopefully be a thing of the past by the time you read this. Our machine was the last of the pre-production prototypes. It is 99.9 percent the way it will be when sold. One of the things, however, that will be changed is the damping action of the front end. Travel there is already more than acceptable at 7.7 in.

Shock absorbers for a machine such as this might present a problem. But Kayaba has those superb gas/oil DeCarbon-designed shocks that we've seen so much of lately. Suzuki uses them on the RM125, Kawasaki on the KX250 and 400, and Red Wing sells them as an after-market product. Each time we encounter them, we are sold more and more on their performance and near indestructability. The Yamaha's shocks didn't alter our opinion. Action is superb. Actually, in their cantilevered position (26 degrees from vertical), which offers 5.7 in. of axle travel, the shocks exceed the needs of the machine. Our lighter staffers felt that while the action of the shocks was outstanding, the springing was a little too stiff. It wasn't anything that they couldn't cope with, just a tad tight. For that same reason, they found that the rear wheel chattered under hard braking. Heavier staffers found neither trait to exist. No doubt the TT500 was designed to suit larger riders.