unique human powered vehicle was developed and patented in the mid 1960s, and first
introduced as "Ground Hugger" in a special plans offering by Popular Mechanics
magazine. Ground Hugger's sleek lines and elegant mechanical design captured the interest
of bicycle manufacturers, worldwide. But the benefits of the recumbent were not widely
understood, and it would be another 10 years before recumbents reached
even low-volume production. Due to today's popularity of recumbents, the original Ground Hugger plans
have been updated and republished. And we've also developed the Ground Hugger XR2 -
a computer-engineered carbon fiber machine utilizing the latest in cycling design and
componentry (click image above).
A major benefit of a recumbent is the awesome
power that a rider can deliver to the pedals. Nearly everyone has enough strength in their
legs to lift up to twice their own weight, and some of us can lift as much as three times.
A recumbent provides the rider with something to push against (the back of the seat), so
total leg power can be delivered to the pedals. In contrast, a conventional bicycle limits
the maximum push against pedals to roughly that of the rider's weight. This, in
combination with its inherently lower frontal area and reduced air resistance, is
responsible for the recumbent's greater speed. The speed record for a recumbent is over 65
mph. In addition, a recumbent naturally positions the body for improved blood flow because
the heart does not have to work against gravity.
Safety in the event of a spill, and virtually zero stress on arms, hands, and low backs
are other advantages. The attribute that receives the most accolades from new riders,
however, is also the most difficult to justify in practical terms. The sheer thrill of
gliding along at 30 mph just inches above the ground puts Ground Hugger in a class of its
own. It's a sensation that has to be experienced in order to be fully appreciated.
Riding a recumbent is an
entirely different experience. One's sense of balance has to be
reoriented to the new seating position and close proximity to the
bicycle's reaction point. Because the ground is a bicycle's reaction
point, the conventional riding position high above the ground translates
into greater lateral distances between opposing lean angles, which means
slower reaction times. A recumbent reacts more quickly because of the
rider's low center of gravity and close proximity to the ground. New
riders initially sense this quick reaction time as instability.
But it's a matter of retraining one's sense of balance - about zero to
15 minutes, depending on the person.
Early versions of Ground Hugger were equipped with the Sturmey-Archer 3-speed hub; the
type with a built-in coaster brake. Plans also show how to install calipers brakes,
lightweight crank and head sets, and a multi-speed derailleur system. The original
frames were built of inexpensive mild steel tubing. But the frame can also be built
of thin-wall 4130-N or aluminum tubing to keep the weight down. The cost to
build Ground Hugger will depend on the type of components and materials you select, and on
whether you purchase new parts individually or buy a used bike and take the components
from it. So the rock-bottom cost-to-build will be on the order of $200 (mild steel
frame with parts from an old bike). But a high-performance multi-speed road bike
with a 4130 frame and new high-end components will cost much more - depending on the
materials and components you select.
may be purchased as 2D CAD drawings and 3D electronic models
(Rhinoceros) in electronic format on CD-ROM, as large 24 x 36-inch prints on bond paper, or in a
set containing both CAD and printed drawings.
(See NOTICE in left margin.)
Length: 88 inches
Weight: 30 - 45 lbs (depending on materials and
Height: 29-3/4 inches (to the top of the handlebars)
Wheel Base: 66-3/8 inches
Front Wheel: 18 X 1.125 inches (optional 16 - 20 inch
Rear Wheel: 26 - 27 inches (optional cross-section)
Gearing: Optional (multi-speed derailleur or hub)
Brakes: Optional (caliper or hub brakes)
longitudinal seat and handlebar adjustment (Fits a 64 - 72 inch
rider height. Frame may be shortened or lengthened for shorter
or taller riders.)