[singlepic id=1768 w=320 h=320 float=left]You’ve got to wonder about the marketing guys at the big four Japanese motorcycle companies, or at least their U.S. subsidiaries. Throughout the ’80s and ’90s, some bright MBA grad would say, “Hey, we sell tons of 50cc motorcycles overseas, and we sell lots of 50cc scooters and mini-bikes in America; we should try importing a full-size 50cc motorcycle!” So they would do it…and the little bike would sell like stocking caps in Miami in July. The company would take a sizable loss, and quickly discontinue the model. And yet, a year or three later, somebody would amazingly try it again, with the expected results.

The 50cc class only blossoms where there are regulatory restraints that prevent buyers from stepping up to larger machines. In many countries, including the UK and Japan, rider licensing requirements make 50cc bikes attractive to riders who would otherwise choose a bigger bike. In the US, no such incentive exists; nearly all states with “moped-class” rider licenses (and/or machine registration) specifically exclude these machines, based either on their higher engine output or their manual gearboxes. In America, these bikes require the same license and registration as the fastest sport bike or the biggest Harley. There is a regulatory difference between 50cc motorcycles and larger bikes, however. At least, there was. From 1979 on, the EPA regulated motorcycle emissions, effectively banishing most two-stroke bikes from our shores. But motors under 50cc were exempted from these regulations for many years. Thus, importing a 2-stroke became practical only when that magic 49cc capacity was retained. Suddenly the 50cc class had a reason to exist stateside.

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All the models listed had really admirable traits: they were fun, light, and frugal. But their peaky powerbands, motorcycle-style, lever-actuated clutches and manual 5- or 6-speed gearboxes meant they were harder to learn to ride than twist-and-go scooters and mopeds, or the semi-automatic centrifugal-clutch 3 speeds found in small Hondas such as the CT90 and C70 step-through. In spite of their tiny bore sizes, they demanded real riders with real motorcycling skills.
These were honest-to-goodness motorcycles. Unfortunately, compared to any other real motorcycle, they were slow. Very slow. Dog slow. Despite funneling more than three to four times the power of a moped engine through a much more efficient, flexible transmission, even the quickest of these little bikes couldn’t hope to exceed the old Federally-mandated 55 MPH speed limit without modification. And, compared to other real motorcycles, they weren’t that much cheaper than bigger, faster 125cc streetbikes and street-legal trailbikes.
It should be noted that European manufacturers such as Italjet, Puch, Derbi and others also attempted to grab a piece of the hot 50cc action. But the bikes they had to sell were even more expensive than the Japanese models, and none of them had enough dealerships to really have much impact on the market.
Because so few 50cc two-strokes have been sold in this country, most motorcyclists have never ridden one. That’s a shame, because one element these have lots of — even compared to bigger bikes — is fun.
[singlepic id=1767 w=360 h=480 float=”right”]I’ve owned two Honda MB5s on which I logged in excess of 8,500 miles, including several overnight trips and least a half-dozen other 400-mile days. My buddy Paul teased me relentlessly about my love for the tiny design. He was a co-worker at the Honda-Kawasaki dealer where I worked, and his daily ride was a much-modified KZ1000. I’ll never forget the day I offered him my MB5 over his lunch break. He came back over an hour later. Tataking off his helmet, his first words were “I’ve never ridden a motorcycle that made me grin so uncontrollably, the whole time, even when I wasn’t doing anything but just riding down the street!
On a 50cc two-stroke, every launch is like a Grand Prix start. The MB5 motor redlines at 10,500 RPM (remarkable at the time), and pulling away from a stop sign requires you to rev it to 8,500 for an authoritative departure, feathering the clutch just ever so much to keep the revs from dropping. Dial in a sub-200-pound wet weight and a width approximately the same a box of Cheerios, and a twisty road (really, really, twisty!) can be an eye-opening bit of nirvana, once you learn to keep the meager motor pumping out its max.
That’s the great thing about these bikes: they actually take more skill to operate than bigger, more powerful machines. Just like Kenny or Freddie or Eddie on their Grand Prix two-strokes, the rider of a 50cc street bike needs to learn how to wring every drop of performance out of his machine…even if he’s going to 7-11. And that kind of disciplined training is hard to get on the streets, given the hyper-performance specs on even midsized sport bikes nowadays.
All the bikes listed are rare, and while they are still largely unloved and affordable, there are more and more collectors looking for them, specially the MB5. If you find any one of these models, snap it up, even if you don’t ride now. I guarantee you that it will be a great way to learn to ride well; if you are already a rider, it will be fun way to learn to ride better.

Aprilia, Puch, Kriedler etc.