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►A full year has passed since the
introduction of the production version of the Bultaco Sherpa T, with the happy
outcome of having achieved the highest goals made for it. During this time it
has, in the hands of masters and novices alike, made a shambles of the
opposition in observed field trials both in this country and abroad. It was
enough better than existing production trials bikes to allow a moderately
experienced rider in the balancing acts to walk off with the golden goodies over
many of the older pros still attempting to coax their heavier, less agile mounts
through the more difficult sections. It had been built for and predicted as the
bike to devastate the competition and revitalize the sport. It has succeeded in
all these. The credit for the
success of the Bultaco trialsbike, built in Spain, must go primarily to an
Englishman, Sammy Miller, for seven years the recipient of the ACU (British FIM
affiliate) star for the top trials rider. Working in conjunction with the
Rickman Brothers concern, designers of Bultaco's motocross machines, Sammy
eventually went direct to the factory to construct the prototype. Miller's
painstaking attention to detail is legend — his careful preparation of ISDT
mounts in the past was done to the last detail. In the '64 contest he even went
so far as to make a special "biter plate" for himself, which when clamped
between the teeth absorbed the jolts of rough riding. His 500cc Ariels, winners
of many a trial from one-day affairs to three and six, were masterpieces of
detail. This same critical attention went into the development of the Sherpa T,
for as Miller stated, "It's just as easy to build a bike that's right as one
that's wrong." He backed that up by convincing Senor Bulta not to begin
production until the bugs were worked out, arguing that the ultimate sales
success depended on approval by the first buyers.
Miller's own machine is
essentially the same as the production rigs, the prime differences being things
that anyone may accomplish, but were felt by the factory to be too expensive to
warrant their inclusion on production models. These are alloy wheel rims,
special handlebar clamps and a group of items Sam sells from his English shop,
called the Sammy Miller Lightning Kit. Let's face it, even with these mods
installed, it still takes a heap o' doin' to hold a candle to the one-and-only
Sam. The pieces referred to would raise the price of near $800 by about $35, not
a lot, but enough to be considered by the factory sales department, and for most
of us the refinements would be superficial — like giving a scalpel to a butcher,
since our efforts at the fine details can just as well be accomplished with a
penknife.
Part of the ease with which the
Bultaco tackles the tough trials sections is-accredited to the engine. It's got
gobs of low-speed torque built right in. Compression is held low to allow easy
firing right from tick-over speeds on up, and multiple flywheels keep it turning
smooth at mile-per-hour slogging. The radially finned head gives best cooling to
the plug at no-motion speed and the small, 24mm carb with a center-position
float keeps venturi velocities high without fuel starvation or flooding at low
rpm and odd angles during the gymnastics of trials riding. Added to this is the
exhaust design — a long, large diameter pipe leading to a small expansion
chamber/silencer, with final exit through a two-bit diameter orifice. This all
couples to give excellent low-end power with good fuel economy by keeping raw
charges inside the cylinder ready to work on the next stroke.
Our test bike was picked up
from Bultaco Western in North Hollywood, California and is the mount Peter
Fraser's been doing so well with in the So Cal Trials Club events. This one is
fitted with lights, an option to suit the buyer's needs. The machine was well
broken-in, tuned for conditions and ready to ride. The fitting of a 4.00 x 18
Metzler sports knob at the rear was to cope with local terrain; sand, decomposed
granite and loose alkali. We were eager to get the bike into familiar ground
where the capabilities could be carefully assayed based on what we were already
familiar with.
No tricky starting drill was
involved, either from cold or once fully warm. The small carb appears to help,
giving high velocities even at cranking revs. At first the feel of the bike was
a little awkward by its obvious extreme light weight, and the rear seating
position afforded by putting the pegs back at the swing arm pivot point is
accentuated by the shortened (1") swing arm itself, under that of the other
models. The placement of the front axle, forward of the lower fork leg to
neutralize steering, brings wheelbase up to standard measure again but continues
to heighten the weight transfer as well as the illusion of riding the caboose.
Even so, the front wheel with narrow 2.75 x 21 tire is not unduly light as
anticipated. To be sure, any snap of the throttle in an uphill attitude would
hoist the rubber clear, but is stayed marvellously well placed for steering when
you needed it. The long-travel (6 ½ inches) forks were a shade stiffer than
seemed necessary for low-speed work although they did a splendid job of
cushioning in the small amount of travel used.
Getting the feel of the Sherpa
took a little time, enjoyably spent — but then even the mighty Miller was off
his stride when he first began on the new mount. When he got the "oneness" with
it he needed it wasn't long until the team had cinched the British championship,
keeping the string unbroken. Once a little more at home ourselves, the thrill
was strong and some venturing into untried areas resulted in a sound sense of
amazement since we were able to tackle and "clean" obstacles which would be pure
folly on most of the other playthings taken into the vale. The low gearing
coupled with that torque-loaded engine did the job. A 13-tooth transmission
sprocket puts a lot of drive into the 50-tooth rear driver, getting low cog down
over 30-to-1 with the engine. The spacing in the gearbox is wide and fairly
constant, thus second and third gears were not without uses in some areas with
little overlap as far as the selection was concerned. I'd reckon top gear to be
a good cruise at 40 mph, though surely in the sixties would be possible, even
with the low (9.1:1) final ratio. The combination makes the Bultaco "T" a
desirable trail machine as well, unless greater fuel capacity is needed. A
speedometer with odometer is fitted, essentially to meet competition
requirements in some areas, but its low mounting position makes it as good as
useless for anything except checking miles when a ride is over. Vulnerable it
is, distracting it is not.
Since in all fairness the
Sherpa T is a specialized trials bike we made no attempt to test it for top
speed or acceleration. It might well prove disappointing in these areas to the
uninformed, for those knowledgeable types acquainted with the demands placed on
a slogging bog-wheeler, suffice it to say that the 244cc engine with its big
bore and short stroke is a revelation at the creeping end of the throttle. Never
once did it falter except through pilot error. The easy-action throttle was
always positive. Negatively the clutch as far as pull is concerned, for the
two-finger method failed us although the action was always firm and response
positive.► |
Bike Tests 
