The Giant Killer: Yamaha 350

(first posted 2/26/2012)    This is Don Emde. There’s a good reason for his big smile. He’s a privateer, and has just won the 1972 Daytona 200, considered to be the most prestigious bike race in the United States.  This is the story about the little bike that made his big smile possible; a classic David and Goliath story with a few twists. It’s one that has captivated me for years.  It could have been you or me pictured here, inasmuch as one didn’t need to be particularly well heeled to own this bike. Except in the talent department.

Just like my hoglet

I told everyone the story about my Italian Harley Hoglet. I’m pretty sure that nothing contained in that story would indicate I possessed much prowess as a rider. I learned how to ride the Hoglet in the mountains and on the street. I even took it to the drag races where my chain broke at the entry to the traps and I slid through with my rear wheel locked. I also survived being driven off the road by drunken soldiers in large cars, Somehow along the way, I felt I had developed the skills necessary to handle more horsepower. I also came to think more horsepower would make me safer.  I still think that was true.

BSA 650

All the soldiers and one of the other sailors who had bikes had settled on the BSA 650 or Triumph 650 as the cool bikes of choice.  I felt woefully inadequate with my 1 cylinder, overweight, Harley 250.  I watched one of the airborne guys  (who I felt was insane before this incident) wheelie across the street and centerpunch a barracks.  I also enjoyed watching those guys when their British iron chose not to start; I knew there were also disadvantages to their choice. It ruined your whole exit scenario to leave the club and have your bike defy you. It is really sort of humorous to watch a drunk trying to kickstart a British bike.  It was helpful to know that the Japanese were making a much better 650.

From Germany via Japan. The best british 650 ever (IMO)

I decided to take my bike and my easy credit to the Yamaha dealer and let him beat me up with a good price on the Yamaha XS1b.  The year was 1971.

Looking back I realize the salesman did not know his product. He looked at my Hoglet and told me he wouldn’t let me test drive the 650 first. He would let me ride the much smaller, lighter, and milder R5 (350cc).  I thought he made a lot of sense although, my Hoglet didn’t weigh much less than the 650.

The 350 was a study in lightweight power with excellent balance. Before we had gone the first block I knew I must have it. I hit the two lane blacktop that led back to Fort Detrick for my test drive. In town I was just going 30-40 and burbling for all the world like a well tuned chain saw. When I hit the city limits I decided to see if it couldn’t do a little more.

More fun than I could handle

I seem to recall going 50 and more than likely was in fourth gear. The bike was smooth as silk and I probably had a mouthful of bugs due to the smile on my face. When you grab a handful of throttle on a two stroke twin or triple things don’t just happen immediately unless you already have it near the boiling point. A two stroke has a sweet spot commonly referred to as a power band. It may be very narrow, say from 5000 to 7000 rpm. It may not be nearly so narrow.  But the band on this little Yamaha was pretty narrow.

So with a smile on my face I grabbed a handful.  Nothing happened.  After a moment the bike began to scream.  Literally.  As the scream started something very strong kicked me in the butt.  The handlebars began to rise and I felt like the rookie I was.

Factory racing TZ350

I know.  What a punk. I’ve said so many times over the intervening years. Those of you who have experienced a two stroke hitting that sweet spot understand just how unprepared I was. Those who have only ridden four stroke street bikes need not criticize. You are just as unprepared as I was. I was also that guy who liked to have a couple beers and hop on my bike. At times like that you need time to think. This bike afforded no time between thinking and doing.  I might have been ok taking it home. However, I certainly had no business taking it to the club and I spent a lot of time there.

With the smile still frozen on my face, I took the bike back to the dealer and thanked him for the experience. I stayed very happy with my Hoglet until I transferred to the southwest desert. Then I sold it and bought another four stroke. I have owned two stroke bikes since that time but I was ready for them and they weren’t nearly the hot rods that the little Yamaha was. In fact, if I had the money I spent buying, building, and tearing up bikes I would be more comfortably retired.

I forfeited my shot at being Don Emde that day.  I never looked back. I don’t know your story but you are welcome to comment below. Don, however, was uniquely qualified and the Daytona race that year was storybook.

Two generations of Daytona 200 winners

Don became the second leg of the only father/son winners in Daytona 200 history;

Don’s father Floyd won in 1948;

Don’s dad represents Indian’s last win;

The Yamaha 350 is the smallest capacity bike to ever win the Daytona 200;

Don was the first Yamaha to win the Daytona 200; (13 straight wins)

Don was the first 2 stroke to win the Daytona 200; and,

Don was that rare privateer winner.

What was special about the Yamaha?  The R5 that I rode was part of an alphabet soup product line that Yamaha developed after an extensive study of the Adler bike produced in Germany. They became the everyman race bike. I cannot begin to tell you how popular they became and if you are old enough, there is no need . So many 750 riders were embarrassed by this bike that it was probably the most loved and most hated bike of it’s generation

Two strokes became very popular in racing because they were lighter and stronger. They have no valves and they have no cams like we are accustomed to seeing.  They were not only lighter but the center of gravity is lower. Since they have no cams etc, it is obvious that tuning involves other factors. Tuning is determined by the size and shape of the piston ports as much as anything. There is blowback in this design in a couple ways. Pistons force the charge back towards the carburetor. Unburned charge is blown out the muffler by the rising piston. To combat these problems Yamaha developed the reed valve with the RD series bike. This, of course, made for a one direction flow on the inlet side.  This came the year after Emde won.

Typical expansion chambers on apparently, a street bike. That got loud!

On the outlet side a tuner would install an expansion chamber. The very small outlet made for a rebounding pulse that forced the unburned charge back into the cylinder before the piston closed the port. Functionally, much like supercharging as it used outside force to sweeten the pot. Obviously much different also as it is all on the exhaust side.

If it’s so crude and sounds like a chain saw, why would anybody want it. It sure isn’t economical with fuel and is arguably less efficient than a four stroke, however, for hauling the freight it is certainly effective.

It has about 60% of the torque of a four stroke according to some of the old tuners. How can it be competitive? The answer is simple. Every stroke is part of a firing rotation. It is 60-70% as efficient but twice as often. When it gets into the power band that it is designed to have, it is just bad. However, it is sure different and scary if you are unprepared.

A humorous note (for me anyway) was the occasional hot rodder who would saw off the ends of his mufflers to reduce back pressure. Inevitably they refused to believe that it was they who had shot themselves in the foot. I understand there can be a similar consequence in altering a rotary engine exhaust.

The much copied 750 Suzuki “water buffalo”

What made Yamaha different was the lack of “unobtanium” in the engines of their racing bikes.  The biggest difference between the works racing bike and the street bike was the weight.  The frame for the works bike had all the brackets for street stuff ground off and was about half the weight of the street model. In other words, the bike that lubricated my underwear that day had the same engine (minus professional tuning efforts) that the “go fast” crowd was using. Yamaha made a batch of dollars by racing what they sold. The street frame had a 27 degree rake for a little more highway stability and the (TZ ) racing unit had a 25 degree rake for quicker response. I see a resemblance between the Miata today and the Yam350 of that day. They were everywhere because they were affordable.

Kawasaki version (750) of terror on two wheels

Don Emde:


Don’s father Floyd retired from racing and opened a motorcycle shop in National City California. Having done my obligatory Navy duty in San Diego, I recognize that as one of the small communities of that metropolitan area.

Don became one of the top amateur riders in California during the late sixties. In 1970 he had a split AMA racing license.  Champions were made by a combination of points earned for road racing, off road, and flat track event. Don was considered an expert in road racing and an amateur for the off road and flat track events. You could not be a “one trick pony” and become the AMA#1.

He rode a Yamaha prepped by a Southern California tuner named Mel Dinesen.  Dinesen was just outstanding. Because Emde did so well in 1970 he was signed by the BSA/Triumph (BSA owned Triumph) effort for the 1971 Daytona 200 competition. He left Dinesen without burning any bridges and took the big contract. The BSA contingent for Daytona was huge. If you are a fan of bike racing these names will be familiar.  If not, please be assured there are AMA#1’s and European legends contained in the group. In that BSA/Triumph team were:  Mike Hailwood, Dick Mann, Dave Aldana, Jim Rice, Gene Romero, Don Castro, Tom Rockwood, Gary Nixon, and Paul Smart.  For a 20 year old it was pretty heady company.

Dick Mann had ridden a 750 Honda in the 1970 Daytona 200. It was the only time Honda tried Daytona to that point and he won. Honda was so happy that they stopped the racing effort and fired Mann. He was so upset that he returned the following year and won again on a BSA. Surprisingly, Emde finished third behind Mann and Gene Romero (both AMA#1’s).

Now you might think that finishing third at the most prestigious motorcycle race in the world would ensure a young racer of a contract the next year. Emde thought so. So did BSA. Unfortunately the business affairs of the world sometimes destroy perfect endings. The next year when the mail showed up it contained a release, not a contract. BSA was bankrupting and the new company was to be Norton Villiers Triumph. A holding company. That company was going to field two bikes the next year and neither of them would be ridden by Emde.

Luckily, Emde had left it open to return to Mel Dinesen. That is a lesson he should have taken to heart. They put together a ride with Team Motorcycle Weekly with backing from Yamaha. The ride was a 350 Yamaha that had been developed with the Daytona 200 in mind.

You might wonder how a 350 could possibly win against 750’s. Good question.  It sure wasn’t horsepower.  The racing version weighed much less than the street version and the rider looked like he could slide through a drinking straw. The Yamaha is reported to produce less than 40 horsepower while the Suzuki and Kawasaki 750’s both produced 75 or more.  The problem was that tire and chain technology did not keep up with the horsepower.

Emde says that there must have been 50 Yamaha 350’s in the race.  I couldn’t confirm  how many, but they were the poor man’s hot rod. Emde rode a very conservative race and paced himself the whole way. Daytona racers were expected to get 200 miles out of a set of tires.  He did.  The Kawasakis and Suzukis did not finish.  He took the lead on the 48th lap of a 53 lap race. He won by about 100 yards over the second place bike.

After winning a David vs. Goliath race like this you might think that a young guy would have discovered all the secrets of success and that they would live happily ever after.  Not so.

Thinking that the tire and chain technology would catch up to the horsepower capabilities, Emde hitched a ride with Suzuki for the 73 Daytona.  The Suzuki team was told the night before the race that the tires would not last for the duration of the race.  The Kawasaki team (Yvonne DuHamel and Art Baumann) crashed into each other very early and left the race. The Suzuki team started developing electrical gremlins and dropping out. Emde babied his tires and finished 7th. He suffered the indignity of watching Jarno Saarinan take first on….. a factory backed 350 Yamaha. Even worse, the Mel Dinesin team took third place with his bike. The following year the little Yamaha didn’t have enough to win but neither did Suzuki or Kawasaki. Yamaha upgraded the mighty TZ and just kept on going.

Emde retired in 1973 to pursue other business interests. He had a severe crash that year from which he says he never completely recovered.  Probably more importantly, that was the year that his friend and mentor Cal Rayborn was killed.  I doubt that the Daytona results of 1973 gave him any reason to want to stay active. He says essentially, that events just made it stop being fun. He has stayed associated with motorcycle sports and his pursuits are an interesting read. The whole Emde family is an interesting read with even his sister being involved in competitive racing. Google them.

The 350 Yamaha had also taken Yvonne DuHamel to a second place finish behind Cal Rayborn’s factory Harley.  Had DuHamel pulled that one out he would share the distinction of being father/son winners of Daytona.  His son Miguel has won four times. Some things are just not meant to be.

There are a lot of untold aspects of this story.  It’s easy to find.  Feel free to kick in with any comments.  I think the larger than life stories of some of these riders are just phenomenal.  Personally, I think it’s harder to ride a bike well than to hit a baseball or throw a football.  But that’s just me.