Steve Cooper looks at how Yamaha took its all-new YR1 and jumped aboard the 1960s street scrambler trend.
In 1967, Yamaha’s Iwata factory rolled out its most significant machine since the 250cc two-stroke YDS1 of 1959.
The all-new Yamaha YR1 350 two-stroke twin was a ground-up design featuring a vertically split crankcase and a clutch mounted on the primary motion shaft. Both features had become the norm by that point for almost everyone except Yamaha, which had stayed loyal to the old German Adler MD200/250 design of the 1950s that had inspired its earlier machines.
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The new YR1 would also go on to lay the foundations for all of Yamaha’s future two-stroke twins, including the later TR and subsequent TZ race machines.
Journalists of the period loved the new motor and its chassis, but they did query the aesthetics. Best described as looking like the love child of Suzuki’s TA/TB twins and an early 1970s MZ, its styling was certainly different.
That said, this column imported one from San Diego and thoroughly enjoyed the experience over several years.
There are some suggestions that a few YR1Cs were produced, but evidence seems to be rather scarce, to say the least. However, 1968 saw the release of a restyled YR2, along with a YR2C street scrambler.
The cylinders had acquired two extra ports based on racetrack experience, which added some vigour to the previous three-port motor. The YR1’s frankly bizarre tank profile was swapped for a much more elegant design, even if the YR1’s side panels were still being used and encroached into the lower rear areas of the new tank.
In place of the YR2’s chrome tank panels, the YR2C came with panels painted in pearlescent white.
The YR2C followed the general lines of the older YDS and YM street scramblers, but was executed with significantly more thought and consideration. Just clearing the top of the engine cases, the silencers were as tucked in as Yamaha could possibly make them. They certainly looked the part, even if they still pushed the rider’s legs out a little.
Other differences from the YR2 included the obligatory braced handlebars and rubber concertina fork gaiters in place of the road bike’s steel shrouds.
Curiously, there does not appear to have been a sump guard offered, even though the contemporary AS1 and CS 125/200 street scramblers were so equipped. Was that an oversight, or was Yamaha deliberately dodging the supposed dual-purpose role of the YR2C? A good question.
Both the YR2 and YR2C were equipped with a powerful twin-leading-shoe front brake, which received praise during road tests for its strong braking performance and effectiveness. Applying that potent front brake on a damp or loose surface, however, could easily have had the YR2C’s rider on their ear.
Despite that strange apparent anomaly, the YR2C sold well enough before being replaced the following model year.
In 1969, Yamaha offered the YR3C, which was, to all intents and purposes, little more than a reworked YR2C. The candy red or candy blue paint options of the 1968 model had been replaced by vivid red or mid-green.
The seat had also been redesigned. Gone was the chrome side trim, replaced by a cover with transverse lines, presumably to add some degree of grip on rougher going — if anyone felt brave enough.
The other key difference was the tank, which no longer had the bolt-on side panels.
Information on the YR3C is scarce, but it was definitely sold in Japan and America. Whether the YR3C was sold into 1970 as a run-out model is up for debate, but there were no more 350cc street scramblers from Yamaha after that.
With no Series 4 models due to superstition around the Japanese character for that number equating to death, the next 350 was the road-going-only YR5. There was definitely no YR5C.
By then, Yamaha had clearly drawn the line between road and off-road bikes — and the two would never blur again in quite the same way.
