Photo courtesy passion-aviation.qc.ca
I recently read a 1960s report, made by an Air National Guard unit, on their experience with the air-cooled Pratt & Whitney 28-cylinder R-4360 radial engine. Much of the report was devoted to the problem of the exhaust valve-seat rings coming loose in the aluminum heads.
As it happens, this has also been a problem with some of the four-stroke motocross engines.
Motorcycles and small towns have long been portrayed as adversaries, from Brando in The Wild One, to that overrated pile of crap Easy Rider, to my personal favorite of the genre—The Wild Angels—in which Peter Fonda, Nancy Sinatra and a bunch of other spoiled Hollywood types play “biker.” At one point the “gang” rides to NorCal to bury a friend: Feeling the need to properly say goodbye to the departed, they wind up taking over a small town church for the ceremony, which somehow transitions from funeral into psychedelic-drug-induced orgy. I must ride with the wrong crowd; all we ever seem to do in small towns is fuel up, grab some grub and occasionally bunk (separately) in a local hotel. Over 25 years of riding and not one spontaneous orgy. What am I doing wrong?
Probably best. My wife has yet to squawk about my riding adventures and I assume one reason is that she knows I’m way more into riding my motorcycle than anything else. Though it probably wouldn’t hurt to just ask about the orgies…
As electric bikes and hybrids seem to take the media’s eye, I wonder if it’s wrong of me to love the simplicity, lightness and power of a two-stroke. Do I need to feel guilty for running a 350cc Twin that might get 25 mpg when I get the engine back in the frame? Where did I leave the frame, anyway? Oh, it’s been a long project, for sure. One of my pals asked, “Where’s the RD?” and the only reply I could think of was, “Where isn’t it?!” because my 1973 Yamaha RD350A is so disassembled and evenly distributed through the places in my life (spare bedroom, garage, office, workshop…).
But I just got the freshly painted engine back from my friend Boris with the paint booth. Even though the engine hasn’t run for years, getting my hands on this little package of dynamite has reminded me that a two-stroke Twin’s sound and fury are wonderful things to behold, and I’m hoping to get my RD back together and making smoke again. Dead dinosaurs ain’t dead yet! Two-strokes are a nice vice. And pass me some of that smokeless tobacco while you’re at it.
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