1974 Yamaha SC500A
This one could be a bit of a challenge, to restore and to ride. For now it is placed against the wall of the garage waiting its turn.
1973 Yamaha SC500 Test
Everybody jabbers on and on about changing the powerband of a motorcycle engine. The scrambles boys want a bundle on top; the MX-ers want a nice, even spread.
Sooo, motors got ported, polished, reeded, drilled, stuffed, files, tampered, folded, spindled and mutilated in the never ending quest for the prefect powerband.
However, only one path has been found to that elusive Perfect Power-band: cubic inches. Or even better, cubic feet.
Yup. You can achieve bottom end, top end and even middle end, if the motor has a big cnough hole in it (and a piston to fit that hole).
Naturally, whenever we get a big-incher in for a test, we expect to be greeted by power. Buckets of power all over the place, Power from idle to peak revs. We expect to put the bike in top gear and go boom-boom-boom down thc road, digging trenches as thc engine barely turns ovcr.
A short while ago, Yamaha dropped off one of their new 500cc bikes at our offices. And promptly blew our preconveived notions about big-inch power right out of the lunch box. Continue reading
1974 125 Motocross Shootout
THERE’S NO doubt about it. The Japanese have been the most instrumental power in bringing the world of small-bore off-road racing to its present level in the United States. Even way back when Yamaha Trailmaster 80s and Honda S90s were bouncing their semi-modified selves around the boonies, things were beginning to take shape. The adage that there is strength in numbers held true once again when, due to the enormous number of these trail bikes showing up at a given race, it wasn’t rare to see both an 80cc class and one for the 90s.
Then along came the Hodakas. First a four-speed 90 and then a five-speed 100. It wasn’t long before the bigger Japanese manufacturers bored their bikes out to 100 and added another gear in the transmission. As these little screamers buzzed their over-stressed guts out week-end after weekend, the European distributors took notice of the tremendous market that was being created. The European machinery was better. It was not much more reliable than the Oriental stuff, but was faster and handled better. Continue reading
1975 Yamaha YZ250B Bike Test
This original test report from 1974 Cycle World tested the first monoshock YZ250b, it was a great bike then and you can see why…..
WE GET ASKED several times a month, through reader letters or at race tracks while testing, what we think is the best 250 motocrosser available today. Our answer has been, “It ain’t been built yet.” Oh sure, the 250 Elsinore is a bullet and it handles well, but trying to turn one is like trying to roller skate on ice.
The first Yamaha YZ was also fast, but it was too pipey, had zilch for tires, a toggle-switch rear brake, and wanted to high side a lot. The Montesa VR was a handling son of a gun, but try to name just three Montesa dealers in your area. Any three. How about two? One? The same goes for Bultaco and Ossa. Nice bikes, but what do you do when one breaks. And they will break, everything does sooner or later.
And what about Husky, Maico and CZ riders? Most of them would be on Japanese bikes if it weren’t for the fact that the only dealers in their counties are a couple of blocks away.
So you see, that elusive motocrosser, the one with the power, the handling, the right carburetion, non-mudding rims, cleated footpegs, gnarly knobbies and the rest of the proper paraphernalia, sitting complete at several dealers’ showrooms right near you just hasn’t been built yet. At least in 1974 it hadn’t been built. Continue reading
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1975, 250, b, Motocross, Vintage, yamaha, yz | 
Leave a comment1975 MX 125cc Shootout
See how the 1975 Honda CR125 compares to the other 1975 models in a test shootout, the Honda is pretty much the same as the 1974 bike with a bit of red colour added, the 1975 Kawasaki KX125 looks like the 1974 model, both these bikes still have the 4 inch rear suspension travel BUT the the radical new Suzuki RM125 comes along in 75 with long travel suspension!!! The Yamaha YZ125C introduced mono-shock suspension and a lot of horsepower into the 125 class.
This is a test that really highlights the pre 75 class with the new breed of mx bikes and a new era then follows. I rode my first real mx season on a 1975 RM125S and it was coool – big sand woops no longer held any fear, full throttle and just hit em hard!!! The RM125 tested here is the US version RM125M, the faster RM125S came to Australia.
SHOOTOUT……… As if you didn’t already know, motocross is one of the fastest growing sports in the country. It’s not hard to see why. Few sports combine action, color, speed, and finesse the way motocross does. And few sports equal motocross in ability to captivate young people, both as spectators and participants. Motocross is real for them. They don’t have to be content to just watch, they can actually do it themselves.
The favorite bikes of teenage riders are the 125s. In fact, most 125 motocross races are dominated by high school and junior high school students. And if any “seasoned veteran” of motorcycling still thinks 125s are nothing more than noisy toys and their riders dumb little kids, he should truck his 250 or 360 down to the local motocross practice track and get his doors blown off by 13-year-old Stevie Squid on his 125 Homazukasaki. As a further humiliation, he may very well learn that Stevie isn’t even one of the 125 hotshoes -he usually finishes somewhere in the middle of the pack. Continue reading
1974 Yamaha MX360 Bike Test
Motocross Action Magazine did a dirt bike test on the Yamaha MX360 in 74 which makes an interesting read if you own , intend to own/race or restore one of these yellow racers as we do:
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“Used to know this dude that lived out in the middle of a big swamp in south Georgia down amongst the cotton mouths, red ants and chiggers. He was what we used to call a good ol’ boy—made downright excellent home brew he called “Mother’s Milk” and had this big, mangy dog he just called “Yaller.” Which made sense, because he was. Continue reading
Yamaha YZ125 Models
See the development of the Yamaha YZ125 from 1973 over the years. Continue reading
1975 Yamaha YZ250B
This 1975 Yamaha YZ250B bike has been sitting around in storage for a very long time, it is still on ORIGINAL BORE!
It was described to me as still having the original piston, original front tyre, original bars and levers, original throttle, original chain and sprockets. The rims are dent free, straight, and true and the bike runs and shifts perfectly…. wow!
It seemed an easy project and needs a little cosmetic work to freshen up its looks, eg replace some of the nuts, repaint engine casing and do a full mechanical check to prepare it for the race track so I bought it and added it to my “to do” list.
1975 YZ250B Tank
1975 YZ250B
1975 YZ250 Engine
1975 Yamaha YZ360B
1975 YZ360B
This is the top of the range in the Pre 75 class, the YZ360B. Even though the “B” model was mainly manufactured in 75 for the US market it actually came to Australia in 1974 so qualifies in the pre 1975 vmx race class!
You beauty, these are almost a straight “works’ bike and are the king of the track and any serious collector wants one.
I was looking for over a year and never found one to buy and I was looking all over Australia and the USA. In the USA they go mainly for the “A” model as it complies withe their pre 75 race rules and those babies sell for upto US$13,000 if you can find one. In Australia we go more for the “B” model.
Unexpectedly one of these YZ360B came up for sale it was all of 1 mile from my house! A fellow club member was selling his treasure and his bike was magnificant, fascidioulsy restored and maintained and setup to hit the racetrack. No effort required by me except to maintain it from here on.
It didn’t take much to get me to write out the cheque and it’s now in my shed, another vmx obsession secured.
It looks great and the detail is first class.
Lesson#: Fellow club members are proud of their bikes and will tell you everything about it and more. They sell good bikes.
A list of what has been performed
- Top end sleeved with standard bore and piston.
- Big end, little end and main bearings replaced.
- Gaskets On Everything
- Exhaust System Sandblasted and Repainted
- Carburettor Reconditioned.
- Throttle (short twist) and Cable.
- Boyesen Reeds.
- New Clamps, Lines and Hoses.
- New K&N Hi Performance Air filters.
- New PVL Germany Electronic Ignition
- New Aluminium Rims
- New Stainless Steel Spokes
- New Wheel Bearings
- New Tyres
- Reconditioned Rear Shock
- New Swing arm Bearings
- New Clutch and Front Brake Cables
- Magura Germany Bar Lever Assemblies
- Renthal Handlebars
- Scott Grips
- Drilled Brake Levers
- Drilled Stabiliser Rod
- New Plastics
- All Fasteners Replated or Replaced
The Way It Was
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