MARTY MOATES AT THE CARLSBAD RACEWAY

In the month of June, during the summer of 1980, Carlsbad Raceway and Marty Moates would become synonymous with one another. On that sunny afternoon Moates, the consummate underdog as an empty-pocketed privateer, rode his LOP Yamaha to victory at the 500cc USGP, a race that until then was dominated by visiting European stars. It was the one race every American rider dreamed of winning, though no one had pulled it off up to that point. But in Cinderella fashion, Moates, born and raised in nearby San Diego, pulled off what remains arguably the single biggest upset in motocross history.

A 1973 works Yamaha 250

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Via : www.vintageworksbikes.com

Featured here is a 1973 works Yamaha 250. The bike was recovered in Sweden and
later restored in the United States.

This bike is believed to have been raced by Hakan Andersson during the first two
races of the 1973 GP Season.

The works motors for 1973 used an all new crank case design made from sand cast
magnesium and featured a new style clutch actuating arm that went through the top
of the cases.

The front and rear wheels are sand cast magnesium as is upper triple clamp. The lower clamp is machined aluminum and the fasteners are titanium. The fuel tank is a hand formed aluminum high capacity tank.
The rear "thermal flow" shocks, still under development, were sand cast in magnesium. The front forks are hand made except for the sliders which are cast aluminum. The fork legs are knurled where they make contact with the triple clamps. Most of the fasteners used are titanium.

The top triple clamp is sand cast magnesium and the bottom, machined aluminum. The forks are machined between
the top and lower triple clams and knurled at the lower clamp for better grip.

The "Thermal Flow" rear shocks were still under development. The lower bodies were sand cast in magnesium... Read More www.vintageworksbikes.com

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Yamaha YZ250

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The YZ250 is a 2-stroke motocross race bike made by Yamaha. It was launched in the 1970s, and has been regularly updated since. It is slowly being phased out and replaced by its four stroke rival, the YZ450F.


The YZ250 has a 249 cc liquid-cooled two stroke reed valved engine with a YPVS exhaust valve for a wider spread of power. The engine produces a peak 46.8 horsepower (34.9 kW) at 8800 rpm and 30.6 foot-pounds force (41.5 N·m) of torque at 7500 rpm, with a 9000 rpm redline (Motocross Action Magazine).


In fact, it is still making 45.0 horsepower (33.6 kW) at 9100 rpm and 41.6 horsepower (31.0 kW) at 9600 rpm before the rev limiter kicks in.
Since its introduction in 1974, the YZ250 has had a single backbone steel frame. For the 2005 model year, however, the YZ250 has a new frame made entirely from aluminum, which brought the dry weight down to 212 pounds.


The bike has a Swingarm rear suspension system with more than a foot of travel, as well as telescopic inverted forks with 11.8 inches (300 mm) of travel. Front and rear hydraulic disc brakes round out the YZ.


The YZ250 holds many championships:

- 5 AMA National Motocross Titles
- 9 AMA National Supercross Titles
- Most recently, Chad Reed rode the YZ250 to an AMA National Supercross title in 2004.





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1979 Yamaha HL 500 Replica

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Via : The BikeExif


Down here in Australia, winter is starting to draw in. We don’t get bad winters—certainly not cold enough to warrant having a ‘riding season’—but when I saw these pictures, I immediately thought that a little snow’s a good thing. Especially if you have a supercool 70s vintage motocrosser in the garage. Like this Yamaha HL500: a bike that’s rare, highly coveted, and talked of in hushed tones. And fair enough: it was the last truly effective four-stroke bike to win a Grand Prix, before the two-stroke domination began.


The ‘HL’ is a reference to the Scandinavians who helped make this Yamaha famous, notably ‘Mr Motocross’ Torsten Hallman and Sten Lundin, although it was Bengt Aberg who grabbed many of the headlines. The motorcycle in the pictures comes from Husky Restorations of New York, a company that specializes in meticulous resto-mods of vintage dirtbikes. It took them three years to make this HL500, using a TT500 engine, YZ400 suspension, and the fuel tank, fenders and seat from a YZ125c. Most importantly, the frame was built by Geoff Morris Concepts (GMC)—one of the best vintage motocross frame experts out there.


I’m no expert on the intricacies of vintage dirtbikes, but I know what I like—and I like the look of this bike very much. Methinks it’s time to get a little log cabin up in the Blue Mountains to the west of Sydney, and put an HL500 replica in the garage. Just the thing to blow out the cobwebs of the working week on a crisp, clear Sunday morning. (Check the Husky Restorations website for a terrific array of images, including Husqvarna 360s and 400s owned by Steve McQueen, Bud Ekins and Bent Aberg.)



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