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►Stay away from Don Vesco.
he thinks 300-plus-mph motorcycling is a perfectly sensible hobby. Maybe a
little unusual, like collecting antique wheelchairs, but really not profoundly
thrilling. Vesco actually believes that. He talks about alarums and excursions
incidental to his demisonic Bonneville travels with the unconcerned humor of a
fisherman spinning tales of broken poles, snarled reels and Big Ones that Got
Away. His record-holding streamliner is now a salt-pocked nine years old, shows
the scars of surgery performed to make it house a succession of ever-larger
engines, and doesn't even have the customary go-fast device's grandiose name.
Don refers to it simply as, "my bike," and sets about preparing it for another
Salt Flats appearance with less trepidation than a touring rider getting his
full-dresser ready for a trip to the Black Hills. Both he and it create the
impression that five-mile-per-minute velocities on two wheels is a game offering
just barely enough risk to be interesting.
The visitor who hangs around Vesco's El Cajon, California,
shop too long may come to share his peculiarly sang froid appreciation of high
speed misadventure, thereby also qualifying for a tie-behind canvas jacket and
calming confinement in a padded room. But the visitor who pays attention will
learn a few things, too, not the least of which is that Don Vesco is a
remarkably astute and clever fellow. He displays a fine grasp of some Bonneville
realities that have eluded many others, and he is clever enough to find simple
solutions to high-speed problems his rivals often try to subdue with complexity.
Mighty Honda (Reaction Dynamics, actually) leaned toward the latter approach,
and got nothing but a bent museum piece and a large bite in the budget for its
Bonneville venture. Vesco opted for utter simplicity and, with a little help
from the right kind of friends, became the once and present holder of
motorcycling's absolute speed record—now pegged at 318 mph.
Vesco did a
lot of Bonneville miles before 1969, when his streamliner was built. His father
took him to the Salt Flats the first time in 1951, when Don was still too young
to drive the family hot rod. ("I took my Thimble Drome model cars," he says.)
He's been to Bonneville at least once each year since 1955, mostly to drive his
dad's streamlined car but usually—exclusively, in recent years—with a motorcycle
or two to ride. The involvement with two-wheeled streamliners began in 1965,
when he appeared for the Speed Week festivities with an old aircraft drop-tank
into which he and the essential elements of a Yamaha TD-1 B 250cc road racer
were inserted. Vesco got this one upside-down while trying to learn to ride it,
the tank being such a close fit he couldn't move or see, and he broke a
collarbone. Friends on the scene weren't really surprised: the tank/bike was
hastily-contrived, and Don's unfortunate habit of crashing and breaking
clavicles was by then firmly rooted in tradition.
That first
streamliner was a more or less conventional motorcycle built inside a small,
stubby WW2-vintage drop tank and its several problems and limitations did not
encourage perseverance. But neither did it dull Vesco's appetite for
all-enclosed motorcycling, and he managed to flimflam Yamaha into providing a
pair of 350cc road racing engines, air-cooled twins, and a smallish budget for
an assault on the then-existing record of 245 mph held by Bob Leppan's twin-engined
Triumph Detroit streamliner. The project wasn't approved until May, 1969, and
had to be completed in time for Speed Week, which meant there wasn't any time to
get fancy.
Nobody in
his right mind would even consider trying to design and construct a
record-attempt streamliner in only two and a half months. Vesco didn't waste
time with fretful consideration; he just did it in his usual direct and artless
fashion. There being no time for a custom-made shell, Don had to scrounge around
for a suitable, larger jet-era fuel tank. The one he found was fully 18 feet in
length, long enough for a recumbent Vesco and two tandem-mounted Yamaha engines
set between widely-spaced motorcycle wheels. It unfortunately was only two feet
in diameter, which meant adding bits of fairing and a prominent canopy to get
inconvenient portions of wheels and rider decently enclosed. Much of the
exterior additions was done in single-curvature aluminum panelling, giving the
shell a long dorsal fin.
It is fair
to say that most of the bike's internal structure virtually designed itself.
Vesco took a sketch and some shell dimensions to a local dragster-frame shop,
where they bent hoops to fit inside the tank and joined them together at
appropriate intervals with straight lengths of the same chrome-moly tubing. Two
of the hoops detoured upward out of round to bring the rider's head within the
roll cage, and these were made of the 11/2-inch diameter, .125-wall material
required for cars by the SCTA. Other tubes were slightly thinner (.063-wall) and
though the main members had a diameter an eighth-inch under that of the
roll-over hoops, some were even smaller. All of the tubes were routed for
convenience—away from the rider's elbows and following the shell's interior
contours—and the finished frame had almost none of the diagonals and
triangulations thought necessary by structural engineers. The workmanship was of
the highest quality; the design lacked elegance. Both facts still hold true, but
through all the years of ever-larger engines and at least one 250-mph crash
Vesco's inelegant frame has done the job.
Vesco's
streamliner began life with and still uses "center-hub" steering. The late, zany
Bert Monroe probably was the last man to fit a streamlined shell over a more or
less conventional front fork. Everyone else figures, correctly, that it's wrong
to have a steering stem and fork bridges standing up above the front wheel to
catch the breeze. Another Bonneville regular, Joe Dudek, put his machine's front
wheel on an oversized hub (actually an old Triumph "springer" rear hub) with an
automotive kingpin inside and a non-swivelling axle inside that. Vesco made his
steering to much the same pattern and attached the through-axle to a kind of
forward-facing swing arm. Originally he made the handlebar attachment with
push-pull cables, which terminated on ears extending out from the hub, but those
gave a rather rubbery and imprecise steering and were soon replaced. His
original rear suspension was built around a lengthened Yamaha TD2 swing arm;
ordinary Girling rear suspension spring/shock units were used at both ends of
the machine.
Don got his
twin-Yamaha quicky 'liner up to a two-way average of 214 mph in 1969, despite
speed wobbles and various other less stimulating teething problems. It wasn't a
bad showing but it wasn't the record either. Over the following winter he
spliced in some longer frame tubes to get an extra nine inches of wheelbase,
replaced the kingpin bushings with ball bearings, and added friction dampers to
help the overworked Girlings. The steering cables were removed and a peculiar
double-Johnson-rod system of tubular links and heim joints installed in their
place. This last task wasn't easy: the streamliner's handlebar swivels at the
end of a long, upward-folding bracket—which has to be lifted for access to the
tube-like cockpit—and the steering links have to fold with the bracket.
A rear tire
blowout at 260 mph caused a crash during Bonneville's 1970 Speed Week, damaging
the streamliner too much for quick repairs. That is, repairs made in time for
more running on the same day. Then there was a gearbox problem (small wonder,
with both Yamaha engines feeding their output to the rear partner's cogs) and
Speed Week ended. Everybody said, "Better luck next year." Vesco was back in
September, the same year, and ran two ways at 251.924 mph. He'd been through the
timing lights faster sliding on the streamliner's side, and his official speed
was a record for only two months. Harley-Davidson sponsored a Dennis
Manning/Warner Riley/
George Smith
streamliner and, in late October, the Cal Rayborn-ridden machine put the record
for bikes up to 266 mph.
Vesco had
the satisfaction of having held the record, however briefly, with only 700 cubic
centimeters of gasoline-fueled engine displacement. It would have to suffice for
a long while. Mother Nature does not always provide enough hard, dry salt to
work up unlimited-record speeds, and she was especially uncooperative over the
next couple of years. Others have fretted and chafed and finally decided that
the Bonneville game just isn't worth its frustrations. Vesco likes the place, in
good years and bad, and is not particularly disappointed to arrive there and
find it's all a salty slush. He's practically an honorary citizen of Wendover;
and if the Salt Flats aren't flat or hard enough for his streamliner, he can
always while away the hours visiting with neighbors or doing a little target
shooting with his ol' buddy the sheriff. And if there isn't enough solid salt to
allow going after the big record, he'll take the little ones, swapping cylinders
and disconnecting engines and switching fuels to get within various class
limits.
One of the
secrets of Vesco's success at Bonneville is that he does take the long view. The
salt may be unrideable today but there's always tomorrow, or next year, or
someday—and to him that's enough promise to justify a lot of preparation.
So he
re-bodied his "bike" for 1972, changed to water-cooled TZ-series Yamaha engines
and did what he could with the running room fate handed him, which included
moving the 250cc record up to 182 mph. The following year went about the same
way, just fooling around collecting class records; but for 1974 Don re-rebodied,
stretched the frame again to house a pair of four-cylinder TZ750 engines and got
serious. The salt wasn't in terrific condition that year but he got in a pair of
runs averaging 282 mph and again had the record, at least in the AMA's eyes. The
FIM doesn't allow repairs between runs, and Don changed a frayed Gilmer belt. It
was a detail he corrected in a large way in 1975, when he overcame handling
problems, two crashes and engine failures to place the official FIM record at
302.928 mph.
Almost
anybody else would have been content, willing to settle for whatever
satisfaction and glory that might accrue to him who pierces the 300-mph barrier.
And almost everybody else was still trying to make that speed seem real, trying
to get it into manageable mental proportions, as Vesco busied himself finding a
sponsor for an attempt at even higher speeds. The real record, in Vesco's
beady-eyed view, is one presently held by Butch Summers. Butch drove the Summers
Brothers car, a four-engined, supercharged, four-wheel-drive streamliner they
call the "Goldenrod," to an absolute record for wheel-driven vehicles of 411
mph. Don Vesco wants to get that record with a motorcycle, estimates it will
take about 425 mph to do it and figures he can manage that speed.
Four-Hundred-and-Twenty-FiveMiles-Per-Hour! That's 37,400 feet per minute, or
the length of a drag strip in less than half a second. The mind, unless it's
Vesco's, boggles.
 I've
forgotten the wheelbase ...if I ever knew. It's about 40 inches longer now than
it was when but I can't remember what It was then. 
Enter, here,
Kawasaki. Yamaha declined to participate in supporting the further travels of
the Vesco Express, its racing budget already committed to activities of a less
esoteric nature. Kawasaki (and Bel-Ray) reckoned it might be nice to have the
record, correctly assumed that Vesco could easily better his earlier speeds and
put the World's Fastest Motorcycle under their company names, decided he might
just beat the Summers Brothers' absolute record, and went for the deal.
Insofar as
the motorcycle record was concerned, Vesco's sponsors bought into a sure thing.
Horsepower certainly wasn't going to be a problem: you turbocharge a pair of
Kawasaki KZ1000 engines and they'll give you enough thrust to make even one of
Wendover's blackjack tables go 300 mph. The other details, which amount to
insurmountable difficulties for people who arrive on the salt as innocent as if
they'd just crawled down from a turnip truck, were already worked out. Those
Kawasaki engines would be tucked into nine years of experience rendered in metal
and the whole assemblage would run through its paces by one who has more Salt
Flats miles behind him than some motorcyclists have ridden on the highway. Phase
One of the program couldn't fail, and it didn't: Vesco handed Kawasaki and Bel-Ray
a nice new 312 mph record for the advertising department tub-thumpers to fondle.
But it wasn't quite as straightforward an accomplishment as the rapidity with
which it was done might make it seem.
The true
nemesis of him who would be King of Motorcycle Speed is steering wobble. The
dynamics of single-track vehicles being what they are, chassis and steering
quivers tend at some speeds to couple up and send front wheels banging back and
forth between the stops. Honda's ill-fated Hawk had this problem,
catastrophically. Harley-Davidson grabbed the record away from Vesco in 1970
mostly because Cal Rayborn was willing to wobble his way through consecutive
passes at nearly 270 mph, controlling his nerves in lieu of being able to
control the steering. Vesco has also had difficulties with steering wobble, but
has found ways to keep the problem within manageable proportions.
One of his
solutions is a technique familiar, in cruder form, to all of us: careful wheel
alignment. But we think we've done a terrific job if the residual misalignment
can't be seen by sighting along tightly
stretched
bits of string. Vesco uses surveyors' plumb bobs and a tooling transit, bringing
the wheels within .005-inch of perfect angular and longitudinal alignment. This
is possible because the streamliner's rear swing arm is mounted on oversize heim
joints tied through lugs in the frame. On-site chain adjustments can be made
without losing the alignment, as machinist's scales are riveted above the axle
slots and indexing lines have been scribed on the tightly-fit axle carriers.
Nobody but
Vesco would have even tried the system of drives he installed with the Kawasaki
engines; nobody but Vesco could have coaxed the lash-up into working. Get this:
he fitted dinky, two-inch-diameter toothed pulleys at the ends of both engines'
crankshafts and has them coupled with a pair of belts only 50 millimeters (1.97
inches) wide. That delivers the output from both turbocharged KZ1000 engines to
the rear unit's clutch and gearbox, which therefore most be subjected to
something in the order of a 400 per cent overload. Not even Vesco believed a
standard Kawasaki clutch would handle that kind of action. He fitted it with a
set of RC Engineering clutch plates and topped them with a pressure plate
carrying a set of springs fit for a railroad freight car. No human hand was
going to be strong enough to compress those springs and release the clutch's
grip, so he rigged a compressed-airdriven servo controlled by a valve linked to
the left handlebar lever.
RC
Engineering contributed other hardware from its supercharged-dragster parts
shelf. The engines were fitted with flatcrown 6:1 RC pistons, which are made
specifically for use in blown engines and have rings located lower than normal
for protection from higher-than-normal combustion temperatures. Little special
preparation went into the cylinder heads beyond fitting the stock valves with RC
valve springs. The non-standard cams, which give the valves a .425-inch lift,
were made for Don by a local shop (Schneider) to suit a particular requirement:
smooth power even at the expense of maximum power. Don says the TZ750 engines he
previously had in his streamliner were just a bit too headstrong for comfort,
gaining output rather sharply with rising revs. He mentions having "spun it out"
at about 160 mph in 1975 as the reason for his smooth-power preference, which
does seem a compelling argument.
Vesco has a bunch of work invested in the Kawasakis' cranks. These have no
non-standard parts (unless you want to count the RC pins at the rods'
small-ends) but have been given "timing-side" main-shafts at both ends. These
are much shorter than the normal left-side shafts, which carry the alternator
rotor and electric starter clutch, and serve two requirements.►
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