Cycle, tensioned spoked wheel assembly and rim therefor

A tensioned spoked wheel assembly with a wheel center plane is disclosed. The wheel comprises a hub with a first hub flange on one side of the wheel center plane and a second hub flange on the other side of the wheel center plane, a rim and spokes or other tensioning means. The spokes which are connected to the first hub flange are, in turn, connected to the rim at a first set of circumferentially spaced points and spokes which are connected to the second hub flange are, in turn, connected to the rim at points which are circumferentially coincident with the first set of circumferentially spaced points. In other words, spokes or tensioning members from first and second hub flanges are paired or grouped at the rim so as to provide a wheel which exhibits, under load, zero, or substantially reduced, by comparison with the prior art, net force vectors parallel to the rotational axis, at any and all given points on the rim, as opposed to a wheel where a spoke from the first hub flange is attached to the rim at a point which is circumferentially spaced a substantial distance from the closest point on the rim where a spoke from the second hub flange is connected. Bicycles having a front wheel, a rear wheel, or a front and rear wheel according to the invention are also disclosed. The bicycle is not susceptible to speed shimmy or wobble, when it includes a front wheel according to the invention.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates generally to spoked wheels and bicycles 
including such wheels. More specifically, the invention relates to 
tensioned spoked wheels which are low in weight, high in stability and 
especially suited for use on bicycles. 
2. Description of the Prior Art 
The art of tensioned spoked wheels is one which dates back well into the 
1800's when such wheels were developed for the Highwheeler bicycles and 
Ordinaries of the 1880's. Prior to that time, compressively loaded spoked 
wheels were standard fare as evidenced by Roman chariot wheels, long ago, 
and, more recently, by the wheels of the Ford Model T automobile. An 
example of the compressively loaded spoked wheel in the context of a 
bicycle wheel is shown in U.S. Pat. No. 452,649 (Powell). 
U.S. Pat. No. 339,550 (Hudson) discloses a tensioned spoked wheel assembly 
from the heyday of the Ordinaries. This patent is particularly concerned 
with the construction of a rim from tubing or sheet metal and includes a 
seam which is protected from the elements by being positioned under the 
tire. In cross section, this wheel assembly is illustrated as having a 
toroidal rim which is wider than a tire mounted on it. 
U.S. Pat. No. 5,061,013 (Hed et al.) discloses a bicycle wheel with good 
aerodynamic properties. The wheel has a toroidal rim with a high aspect 
ratio and a width exceeding the width of a tire to be mounted on it. FIG. 
4 of the patent illustrates a wheel with 14 spokes. This is a reduced 
spoke count wheel in the sense that modern mass-produced bicycle wheels 
typically have 32 to 48 spokes. This is a conventionally spoked wheel in 
the sense that the outer ends of the fourteen spokes are connected to the 
rim at 14 points which are evenly spaced about the circumference of the 
rim. The inner ends of the fourteen spokes are connected to the hub with 
seven spokes on each side of the hub. The fourteen spoke wheel illustrated 
in FIG. 4 of the patent is a conventional radial spoked wheel. It is worth 
noting that the United States Cycle Federation (USCF) enforces a sixteen 
spoke minimum, per wheel, for bicycles involved in sanctioned, mass-start 
races. This type of spoking will be referred to herein as conventional 
spoking. 
U.S. Pat. No. 2,937,905 (Altonburger) discloses a rim configuration with a 
novel spoke connection in which the spoke nipple rests upon a surface 
which is canted so that spoke forces are well distributed on the nipple 
seat portion of the rim. 
U.S. Pat. No. 4,583,787 (Michelotti) discloses a nipple seat bushing which 
is slanted to achieve a better stress distribution. U.S. Pat. No. 
4,729,605 (Imao et al.) discloses a spoke with a fiber reinforced central 
portion and two fittings, one at each end of the central portion. 
Tests have shown that each spoke of a modern quality bicycle wheel has an 
elastic limit, or yield point, of +300 kg in tension, approximately 4 
times static tension. Since this yield point exceeds the total 
rider-machine weight by a factor of approximately 3 for an 175 lb rider 
and 25 lb bicycle, builders have become more daring in lowering spoke 
count. The minimum acceptable spoke count for mass-start United States 
Cycle Federation sanctioned races is 16 for a tensioned wheel. 
Conventional tensioned wheels with spoke counts below this have poor 
structural characteristics and become dangerously unstable and endanger 
not only the individual user but also other ride-race participants. 
Specifically, these low spoke count conventional wheels induce a steering 
input under load which becomes proportionately larger with each additional 
spoke count reduction and exhibit varying friction at the wheel-tire road 
contact point at a lean angle in turns. Measurements show that on a 
conventional fourteen spoke radially laced front wheel, the wheel axle 
departs from the horizontal, alternately dipping on the left side by net 
0.015 inches when a right spoke passes over the wheel-road contact point 
(RCP) and then dipping net 0.015 inches on the right side when the next 
spoke, a left spoke, passers over the RCP. These horizontal position 
changes of the axle are measured with a 150 lb load applied at the axle at 
wheel center through the bicycle fork and are measured from axle center at 
the fork dropouts to the RCP on a 700C conventional fourteen spoke 
radially laced front bicycle wheel. Measurements show that the distance 
from the axle at the right dropout to the RCP decrease by 0.010 inches 
under load compared to the no-load distance as a right spoke is centered 
over the RCP and the distance from the axle at the left dropout to the RCP 
decreases by 0.025 inches under load compared to the no-load distance as 
the same right spoke is centered over the RCP. These differential distance 
variations result in a net 0.015 inch departure of the axle from the 
horizontal at the fork dropouts and this departure alternates from a low 
left dropout with the passage of a right spoke over the RCP to a low right 
dropout with the passage of the next, a left spoke, over the RCP. The 
rider experiences these horizontal axle position changes as alternating 
left to right and right to left steering inputs at the handlebar with the 
steering bar experiencing a direction reversal with the passage of each 
spoke over the RCP as the wheel rotates under load. The fourteen spoke 
wheel under discussion exhibits 14 such steering pulses per wheel 
revolution. With a higher spoke count conventional tensioned wheel these 
net axle departures from the horizontal become less and move to 0 for a 
solid wheel and these departures become more with a further reduced spoke 
count. 
The amplitude and frequency of these steering vibrations are inversely 
proportional, the kinetic energy per cycle driving them being constant. As 
wheel rotation speed goes up, frequency goes up and amplitude goes down. 
As rotational speed goes down, amplitude goes up and frequency goes down. 
This tends to obscure the phenomenon to the inattentive rider. Energy is 
consumed by these vibrations, detracting from overall vehicle efficiency. 
As well, internal stresses are created in the wheel which eventually lead 
to system failure even if the wheel is run on a glass-smooth surface for 
its life cycle. In addition, these vibrations at the steering bar limit 
the lean angle a cyclist can achieve in a high-speed turn, where a 
constant steering angle is essential for safety once a lean angle has been 
established. These conventional wheel-induced steering inputs make a 
constant steering angle impossible. These steering inputs can also be the 
source of hitherto unexplained wheel shimmy on high spoke count 
conventional wheels when a highly tensioned spoke lies next to a low 
tensioned spoke as characteristically happens at the wheel-rim seam. 
Almost all wheels exhibit a variation in spoke tension at this point in 
the wheel and the net differential dip at the front dropouts will be much 
greater than 0.015 inches if adjoining spoke tension departs 
significantly. This greater steering pulse can at certain speeds, in 
concert with fork and frame characteristics, vehicle load distribution and 
rider-induced frame flex, cause sudden, uncontrollable and extremely 
dangerous shimmy during high vehicle speed. 
At the rear of the bicycle the low spoke count conventional wheel cannot 
exhibit axle departure from the horizontal as the position of the dropouts 
is fixed in space by the closed triangles formed by the seat stays, chain 
stays and seat tube, the dropouts being attached at the intersection of 
the seat and chain stays. Axle movement being thus restricted, the 
geometry of the conventional wheel, specifically the spoke pattern, pulls 
the rim out of the center plane of the wheel at the RCP under load. The 
conventional fourteen spoke radially laced front wheel was tested under a 
150 lb load applied at the axle with the axle locked in fixture 
restricting any axle movement as it would be were it installed at the rear 
of a bicycle and the departure from the wheel center plane of the rim was 
measured at the RCP. During this test the RCP was free to move and the 
axle was fixed. The wheel exhibited a lateral departure of 0.100 inches 
out of its center plane away from the spoke centered over the RCP. That 
is, when a right spoke was centered over the RCP the rim was deflected to 
the left and when a left spoke was centered over the RCP the rim was 
deflected to the right. The RCP would thus describe a sine wave over the 
road surface with an amplitude of 0.200 inches; 0.100 inches on each side 
of the wheel center plane as successive alternate spokes pass over the RCP 
with the distance between adjoining right peak side departures measured 
along the vehicle center line of travel being equal to the distance 
between adjoining right spokes projected to the RCP. These lateral 
side-to-side deflections of the rim at the RCP of a loaded moving rear 
conventional wheel cause excess stress in the wheel and lead to early 
system failure, even if the wheel is always ridden on glass-smooth 
surfaces. Also, energy is consumed by the forces deflecting the rim 
laterally and this again detracts from overall system efficiency. During 
high speed cornering these side-to-side deflections severely limit the 
lean angle because road contact friction is severely pulsed going from a 
minimum to a maximum and back with the passage of successive spokes over 
the RCP. 
The differential up and down rocking of the front fork dropouts and the 
lateral rear rim deflection at the RCP in loaded dynamic conditions of 
conventionally spoked tensioned wheels are caused by the existence of a 
horizontal force gradient (considering the wheel center plane as 
vertically oriented) in the rim between the spoke-rim contact points. The 
force applied by each spoke at the rim can be resolved into horizontal and 
vertical components and a typical horizontal component is 23 lbs. Thus a 
left spoke tensioned to about 150 lbs (typical) pulls the rim to the left, 
out of the wheel center plane with a resolved force of about 23 lbs. The 
next spoke along the wheel rotation will be a right spoke and it pulls the 
rim to the fight by about 23 lbs if uniform tension exists. In an unloaded 
conventional wheel these forces are in balance and the rim is centered in 
the wheel center plane which lies halfway between the dropouts and a force 
gradient perpendicular to the plane of the wheel exists from spoke to 
spoke along the rim. On a low spoke count conventional wheel the distance 
along the rim between spokes becomes greater going from about 2 inches on 
a conventional thirty six spoke 700C rim to 5.25 inches on a conventional 
fourteen spoke wheel of the same diameter. Thus as any given spoke passes 
over the RCP on a low spoke count conventional wheel the adjoining spokes, 
the one directly ahead and behind, carry relatively less of the load and 
remain relatively high in tension and since each of these directly 
adjoining spokes is of opposite orientation of the main load carrying 
spoke and since this main load carrying spoke is severely reduced in 
tension, no countervailing or a severely reduced countervailing force 
vector remains and thus no alternating force vector remains to balance the 
horizontal force vectors of the adjoining spokes. If a right spoke is 
positioned over the RCP and it is substantially unloaded in tension by the 
system load its horizontal force vector along with its vertical force 
vector is essentially reduced to a very low value and the adjoining spokes 
being both of left orientation pull the rim unopposed to the left. As the 
conventional bicycle wheel rolls along under load the next spoke to become 
unloaded by the system load will be a left spoke and the rim will be 
deflected to the right resulting in a zigzag trace of the RCP along the 
wheel line of travel if a print were left by the RCP on the pavement. With 
further reduction in spoke count in a conventional wheel the amplitude of 
the zigzag trace will increase and with a greater spoke count the zigzag 
trace will decline in amplitude, going to 0 for a solid wheel. 
In order to reduce the weight of tensioned spoked wheels, wheel makers have 
looked to low spoke count wheels such as the fourteen spoke wheel 
disclosed in Hed et al. Such a construction, however, suffers from 
instability and the origin and consequences of this instability are 
discussed herein in great detail. In Hed et al., it is suggested that one 
can produce a reduced spoke count wheel with as few as eight spokes if one 
uses a rim that is stiff and strong enough. As explained herein, the need 
for a stiff rim in low spoke count, conventionally laced wheels arises 
because of a practical limitation on the minimum number of spokes that one 
can use in making a conventional tensioned spoked wheel. Specifically, in 
such wheels, there are certain side loads that are unresolved by the 
spokes and are resolved only in the rim. Resolution of these loads in the 
rim creates a steering input in front wheels. Generally speaking, as the 
number of spokes per wheel is reduced, the magnitude of these forces 
increases until a point is reached at which conventional rims simply can't 
hold up. One answer, suggested in Hed et al., is to use a stronger rim but 
this almost necessarily involves additional mass, however, and the goal of 
a reduced weight wheel is subverted in the process. 
There remains a need for a reduced spoke count wheel which does not require 
a super strong rim. There is also a need, particularly in the context of 
reduced spoke count wheels, for improved stability with respect to lateral 
loading. 
SUMMARY OF THE INVENTION 
The present invention is based upon the discovery of an improved tensioned 
spoked wheel assembly which exhibits improved stability, for a given spoke 
count, by comparison with prior art wheels containing the given number of 
spokes, and even by comparison with prior art wheels containing 
substantially more than the given number of spokes. According to the 
preferred embodiment of the invention, a tensioned wheel is disclosed 
which, in its ideal embodiment, exhibits, under load, no net force vectors 
parallel to the rotational axis, at any and all given points on the rim 
where groups of spokes are arranged in single or multiple pairs where the 
distance between spokes of each pair, as measured along the inner wheel 
rim circumference in the center plane of the wheel, is zero and the pairs 
or groups of pairs are evenly spaced around the inner circumference of the 
rim so that each pair of spokes defines a plane which is perpendicular to 
the center plane of the wheel. In this embodiment, spokes from a first 
side of the hub are routed to and connected to the rim at a point which is 
on the first side of the center plane of the wheel and spokes from the 
other, second side of the hub are routed to and connected to the rim at a 
point which is on the second side of the center plane of the wheel. In 
this embodiment, there is simply no unresolved horizontal forces applied 
by the spokes to the rim; the spokes of each pair exert lateral forces on 
the rim which are equal in magnitude and opposite in direction canceling 
their respective resolved horizontal force vectors. In a modified form of 
this embodiment, pairs of spokes are connected to the hub at points which 
define a line which is not perpendicular to the center plane of the wheel 
and substantially canceling their respective horizontal force vectors. 
In another embodiment, spokes are arranged in pairs, groups of pairs or 
clusters of pairs where the distance between the spokes at the end of each 
pair, group of pairs or cluster of pairs, as measured along the inner 
circumference of the rim is significantly less than the distance between 
the adjoining pairs, groups of pairs or clusters of pairs. By 
significantly less, it is meant that the relationship between the two 
distances is such that, by comparison with prior an wheels, a wheel 
according to the invention exhibits substantially less unresolved or 
unbalanced horizontal forces applied by the spokes to the rim. In this 
embodiment, the spokes in each pair group or cluster do not lie in a plane 
that is perpendicular to the center plane of the wheel. In this 
embodiment, spokes from a first side of the hub can be connected to the 
rim at a point which is either on the first or second side of the center 
plane of the wheel and spokes from the other, second side of the hub are 
connected to the rim at a point which is on the opposite side of the 
center plane of the wheel from the point where the spokes from the first 
side are connected to the rim. In the case where the spokes cross the 
center plane of the wheel, it is preferred that each pair of spokes is 
connected to the rim opposite each other and at the same point along the 
inner wheel rim circumference. This construction provides outstanding 
lateral stability and resistance to lateral deflection under external 
lateral loading. 
Accordingly, it is an object of the invention to provide a tensioned spoked 
wheel with a spoke configuration which eliminates or reduces internal, 
unresolved lateral spoke force vectors in the rims associated with prior 
art wheels. 
It is a further object of the present invention to push back the frontiers 
of reduced spoke count wheels by providing a wheel construction with 
remarkable stability even at severely reduced spoke counts. 
It is a further object of the invention to reduce or eliminate unresolved 
lateral force vectors in rims as an internal source of dangerous steering 
inputs and/or lateral rim deflections. 
These and other objects and advantages of the present invention will no 
doubt become apparent to those skilled in the art after having read this 
detailed description of the invention including the following description 
of the preferred embodiment which is illustrated by the various drawing 
figures.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIGS. 1 and 2, an eighteen spoke, tensioned radially spoked 
wheel according to the present invention is indicated generally at 10. The 
wheel 10 comprises a largely conventional hub 12 with first and second 
opposed hub flanges 14 and 16. The wheel 10 has a rim 18 and is laced to 
the hub 12 with 18 conventional spokes 20, each having a first, inner end 
22 and a second, outer end 24. The lacing of the spokes 20 is 
unconventional and, as shown in FIG. 1, the spokes 20 are grouped into 
nine pairs and each pair is connected, at its outer end, to the rim 18 at 
two points. Neither point is in the center plane (CP shown in FIG. 5) of 
the wheel 10 and the points define a line which extends perpendicularly to 
the center plane of the wheel and which extends in a direction that is 
parallel to the axis of rotation A of the wheel 10. The ends 22 of the 
spokes 20 are connected to the hub flanges 14 and 16. 
The hub flanges 14 and 16 are positioned so that spoke apertures, indicated 
at 26, are aligned as between the flanges 14 and 16 so that, as shown in 
FIG. 2, there is no radial offset between the ends 22 of the spokes 20 of 
each pair of spokes. This is preferred, although it is within the scope of 
the invention to have offset apertures in the hub flanges 14 and 16. 
Beyond that, it is considered to be within the scope of the invention to 
connect the hub ends of spokes to opposed hub flanges so that the points 
of attachment at the hub flanges are substantially circumferentially 
offset from one another. 
Referring now to FIGS. 3 and 4, a three cross, tangentially spoked 36 spoke 
wheel according to the invention is indicated generally at 40. The wheel 
40 comprises a largely conventional hub 42 with first and second opposed 
hub flanges 44 and 46. The wheel 40 has a rim 48 and is laced to the hub 
42 with thirty six conventional spokes 50, each having a first, inner end 
52 and a second, outer end 54. The lacing of the spokes 50 is similar to 
the lacing shown in FIGS. 1 and 2 for the wheel 10 in that, as shown in 
FIG. 3, the spokes 50 are grouped into eighteen pairs and each pair is 
connected, at the outer ends 54 of the spokes, to the rim 48 at two 
points. Neither point is in the center plane (CP shown in FIG. 5) of the 
wheel 40 and the points define a line which extends perpendicularly to the 
center plane of the wheel and which extends in a direction that is 
parallel to the axis of rotation A of the wheel 40. The ends 52 of the 
spokes 50 are connected to the hub flanges 44 and 46. 
The hub flanges 44 and 46 are positioned so that spoke apertures, indicated 
at 56, are aligned as between the flanges 44 and 46 so that, as shown in 
FIG. 4, there is no radial offset between the ends 52 of the spokes 50 of 
each pair of spokes. This is preferred, although it is within the scope of 
the invention to have offset apertures in the hub flanges 44 and 46. 
Beyond that, it is considered to be within the scope of the invention to 
connect the hub ends of spokes to opposed hub flanges so that the points 
of attachment at the hub flanges are substantially circumferentially 
offset from one another. 
A rim, constructed in accordance with the present invention, is indicated 
generally at 60 in FIG. 5. The rim 60 has a tire mounting surface 62 with 
nipple tightening apertures 64, a nipple flange 66, and an inner rim 
surface 68 with spoke apertures 70. A reinforcing flange 71 connects and 
is connected to the tire mounting surface 62, the nipple flange 66 and the 
inner rim surface 68. Preferably, the rim 60 is formed by extrusion. 
First and second spokes 72 and 74 constitute a spoke pair and the details 
of their relationship to each other and to a wheel according to the 
invention will now be discussed in further detail. A hub, indicated 
generally at 76, has first and second hub flanges 78 and 80 with spoke 
apertures 82 for receiving spoke ends 84 and 85. These hub flanges 78 and 
80 are preferably aligned axially, meaning that a line connecting an 
aperture 82 in flange 78 with an opposed aperture 82 in flange 80, would 
extend in a direction parallel to the axis of rotation A of the hub 76. 
Deviations from this alignment fall within the scope of the invention, but 
alignment parallel to the rotational axis is preferred. Outer ends 86 and 
87 of the spokes 72 and 74 pass through the spoke apertures 70 in the 
inner rim surface 68, through spoke apertures (not numbered) in the nipple 
flange 66 and are secured to nipples 88. The nipple flange spoke apertures 
are positioned to be aligned, in accordance with a preferred embodiment of 
the invention, so that a line connecting the center points of the nipple 
flange spoke apertures would extend in a direction parallel to the 
rotational axis A of the hub 76. This is preferred although it is within 
the scope of the invention to have some circumferential offset between the 
nipple flange spoke apertures and the inner rim surface apertures 70. In 
the most preferred form of the invention in the context of a radial spoked 
wheel, illustrated in FIG. 5, the plane defined by the spokes 72 and 74 
contains the rotational axis A. In the context of a tangentially spoked 
wheel, such as that shown in FIGS. 3 and 4, in the most preferred 
embodiment of the invention, the plane defined by two spokes in a pair is 
parallel to but does not intersect the rotational axis A of the hub. In 
these two embodiments, the spokes 72 and 74 are symmetrical about the 
center plane CP, and it is this symmetry, lacking in all prior art known 
to the applicant, which gives wheels according to the preferred 
embodiments of the invention, remarkable stability neutralizing the 
lateral force vectors of the spokes to zero at all points around the rim. 
In the case of a rear wheel which is dished, physical symmetry is not 
possible, of course, but, according to the invention, symmetrical forces 
are applied by the spokes relative to the center plane, even where 
physical symmetry is lacking. The force symmetry is achieved through 
differential tensioning so that there are opposed spoke vector forces 
(equal in magnitude and opposite in direction). 
Another embodiment of a wheel according to the invention is indicated 
generally at 90 in FIG. 6. In the wheel 90, first and second spokes 92 and 
94 each cross the center plane CP of the wheel 90 between a hub 96 and a 
rim 98. Because the spokes 92 and 94 do not intersect, they can not define 
a plane which is parallel to the rotational axis. However, it is 
preferred, in the crossed spoke embodiment, to come as close as practical 
to having a spoke pair consisting of spokes 92 and 94 define a plane 
parallel to the rotational axis and, in the case of a radially spoked 
wheel, containing the rotational axis. 
It is believed that a further understanding of the invention will be had 
from a discussion of certain prior art wheels which are illustrated in 
FIGS. 7 through 11. 
FIG. 7 is based upon FIG. 4 of the previously identified Hed et al. patent 
and it shows a radially spoked fourteen spoke wheel W mounted in a fork F. 
The fourteen spokes have been numbered 1-14. Odd numbered spokes are all 
connected to a right hub flange F.sub.1 and all even numbered spokes are 
connected to a left hub flange F.sub.2. The outer ends of all of the 
spokes are connected to the rim R and the spokes are evenly spaced about 
the inner circumference of the rim R, 25.7 degrees apart (360 degrees 
divided by 14). 
A 14 spoke rim according to the present invention has 14 spokes grouped 
into seven pairs and each pair of spokes is evenly spaced about the inner 
circumference of the rim, 51.4 degrees apart (360 divided by 7). 
Notwithstanding the fact that the circumferential distance between spokes 
is doubled in a wheel according to the present invention, by comparison 
with the prior art as illustrated by Hed et al., a wheel according to the 
present invention has been shown to be more stable than the prior art 
wheel, by tests which are described below, following a description of 
another prior art wheel illustrated in FIGS. 8 and 9. 
A prior art, tangentially spoked wheel W, is illustrated in FIGS. 8 and 9. 
The wheel W has thirty six spokes S and each one is connected, 
equidistantly and successively, to a rim R at circumferentially spaced 
points. Specifically, each spoke is connected to the rim, in the center 
plane of the wheel W, and spaced apart from adjacent spokes by 10 degrees 
(360 degrees divided by 36). Like the wheel W shown in FIG. 7, the wheel W 
in FIGS. 8 and 9 has spokes which alternate between a first hub flange F1 
and a second hub flange F2. In contrast, a tangentially spoked 36 spoke 
wheel according to the present invention, has pairs of spokes spaced 20 
degrees apart from adjacent pairs, as shown in FIGS. 3 and 4. 
Wheels according to the present invention have been tested against some 
prior art wheels in order to compare rim rigidity in a wheel according to 
the present invention with rim rigidity in prior art wheels. The wheels 
were tested in the following manner. 
A wheel was mounted in a Park wheel trueing stand which firmly holds a 
bicycle wheel axle with no discernable deflection when moderate loads are 
applied to the wheel. A load of 23 lbs. was applied to the rim, in a 
direction parallel to the axis of rotation of the wheel, and the 
deflection of the rim, in that direction, was measured. In each case, the 
load was applied sequentially to each side of the rim at a point 
immediately adjacent to the point where a spoke, or, in the case of the 
present invention, a pair of spokes, was connected to the rim. 
Before testing, each wheel was built, by the same builder, with Phil hubs, 
to uniform standards, with the recognition that complete uniformity is not 
possible with bicycle wheels. During testing, multiple measurements were 
taken on each side of the rim and each deflection was recorded. Results, 
reported herein, are averages of these measurements. In the table below, 
test results are reported for nine control wheels, identified C1 through 
C10, and 2 wheels made in accordance with the preferred embodiment of the 
invention, identified Ex1 and Ex2. Some of the wheels were radially laced 
and others were Tangentially laced; the latter type are identified by a 
number, other than 0, in the column headed "Number of Spoke Crosses". The 
term "tubular" identifies a rim which is designed for a sew up or tubular 
tire. 
______________________________________ 
Number of 
Rim Type/ Number spoke Deflection 
Example or 
weight (g) 
of spokes 
crosses in inches 
Control ID 
______________________________________ 
FRONT WHEELS 
Matrix ISO C/ 
32 3 0.250 C 1 
500 
Sun M19A/ 14 0 0.271 Ex 1 
350 (tubular) 
Matrix ISO 
32 3 0.285 C 2 
CII/405 
Mavic Open 
28 0 0.360 C 3 
4CD/450 
AMBROISIO 12 0 0.401 C 4 
AERO 
dynamic 
DUREX 
marchio 
depositato 
allumag 
monocellulare/ 
500 (tubular) 
Araya Aero4/ 
14 0 0.417 C 5 
350 (tubular) 
REAR WHEELS 
Sun M19A/ 20 2 0.257 Ex 2 
350 (tubular) 
Matrix ISOC/ 
36 3 0.265 C 6 
500 
Mavic Open 
36 3 0.280 C 7 
4CD/450 
Matrix 36 3 0.295 C 8 
ISOCII/405 
Sun (19.3 mm 
20 2 0.310 C 9 
rim width)/ 
400 
(estimated) 
Mavic Open 
32 3 0.345 C 10 
4CD/450 
______________________________________ 
The data reported in the preceding tables demonstrates that a wheel 
according to the present invention, has excellent lateral stability at the 
rim, even by comparison with higher spoke count wheels. For example, Ex1 
wheel, a 14 spoke radially laced wheel according to the invention 
exhibited 0.271 inch deflection. The only front wheel with lower 
deflection was C1, a 32 spoke, tangentially laced, three cross wheel. The 
Ex1 wheel had lower deflection than another 32 spoke, tangentially laced, 
three cross wheel, namely, C2. By comparison with C4, a 14 spoke radially 
laced wheel according to the prior art, Ex1, with 14 spokes laced, 
according to the present invention, with 7 pairs of spokes defining planes 
parallel to and intersecting the rotational axis, had 35% less deflection. 
The rear, tangentially laced wheel according to the invention was Ex2, and 
it had less deflection than all of the control rear wheels, laced 
according to the prior art, that were tested. 
The foregoing static analyses of prior art wheels and wheels according to 
the present invention explains the relationship between conventional 
spoking and axle deflection and lateral deflection at the rim, under load. 
The problems which arise in a dynamic bicycle system including 
conventionally spoked wheels will now be considered vis a vis the 
advantages of a dynamic bicycle system including a front wheel according 
to the present invention. 
The subject of speed wobble or shimmy in bicycles has received much 
attention because it is extremely dangerous. Shimmy is known to occur in 
bicycles having front wheels that are conventionally spoked. Speed wobble 
or shimmy is used herein to refer to a condition where the entire front 
end of a bicycle oscillates at a frequency of several times per second and 
wherein the steering bar and the head tube moves laterally a substantial 
distance during each oscillation. The distance can be more than one inch 
in severe instances and a rider of a bike which is oscillating to this 
extent at high speed is in a "frightening situation." John Kukoda, 
Bicycling, April, 1992, page 152. Theories abound about how to stop shimmy 
when it occurs. According to John Kukoda, 
"factors [which contribute to speed shimmy or wobble] include a tight 
headset that inhibits free turning of the fork; a short wheelbase and or 
chainstays; frame flexibility along the top tube (especially in large 
frame sizes); light wheels; untrue wheels; insufficient trail (usually the 
result of too much fork rake on a frame with a steep head tube angle); a 
heavily loaded handlebar bag; flexy loaded racks; and improperly packed 
panniers that allow the load to shift side to side." 
Until now, no one has addressed the problem to the extent needed to provide 
a system in which the onset of shimmy is prevented. For the reasons 
discussed below, a bicycle according to the present invention is not 
susceptible to speed wobble or shimmy. 
The present analyses begins with the recognition that all wheels deform, to 
some extent, at the road contact point (RCP) under load. As a consequence, 
when a wheel is loaded, the radius of the wheel between the hub and the 
RCP is reduced and the radius elsewhere in the wheel is increased. There 
is a flat spot in the rim adjacent the RCP in a loaded wheel. The length 
of the flat spot is proportional to the pliability or flexibility of the 
rim. In a tensilely spoked wheel, the flat spot phenomenon partially 
unloads the spokes at and near the RCP while the tension in the other 
spokes is increased. 
Referring now to FIGS. 10 and 11, there is illustrated a conventionally 
radially spoked 14 spoke front wheel W mounted in the fork F of a bicycle 
frame (only a portion of the frame F is illustrated in FIG. 11). The 
fourteen spokes have been numbered 1-14. Odd numbered spokes are all 
connected to a right hub flange F.sub.R and all even numbered spokes are 
connected to a left hub flange F.sub.L. Only spokes 1-8 are shown in FIG. 
10. Let's consider the case, discussed above in the description of the 
prior art section, where each spoke in the wheel W (FIGS. 10 and 11) is 
loaded with a 200 pound tensile force when the wheel is unloaded. When a 
one hundred and fifty pound load is applied downwardly through the fork 
which comprises a fork crown FC, a right fork blade FB.sub.R and a left 
fork blade FB.sub.L, the load is split between the fork blades FB which 
transmit 75 pound loads through fork ends FE.sub.R and FE.sub.L to the 
ends E.sub.R and E.sub.L of an axle A. Spoke 8 intersects the RCP and has 
its tension reduced approximately 75 pounds so that its tension is reduced 
to about 125 pounds. As noted previously, measurements show that, under 
the stated load with spoke 8, which is attached to the left hub flange 
F.sub.L, centered over the RCP, the left end E.sub.L of the axle A 
deflects downwardly, as indicated by the arrow D.sub.L, 0.010 inches while 
the right end E.sub.R of the axle A deflects downwardly a distance of 
0.025 inches as indicated by the arrow D.sub.R. When the wheel W is 
rotated so that a spoke such as 7 that is attached to the right hub flange 
F.sub.R, is centered over the RCP (not shown), the left end E.sub.L of the 
axle A deflects downwardly 0.025 inches (not shown) while the right end 
E.sub.R of the axle A deflects downwardly a distance of 0.010 inches (not 
shown). In the fourteen spoke wheel W under consideration, assuming all 
spokes are in equal tension, during one revolution under load, the axle A 
will depart from a horizontal orientation 14 times a distance of 0.015 
inches over its length, seven times at the left end E.sub.L of the axle A 
and seven times at the right end E.sub.R of the axle A, alternatingly. 
These deflections generate forces which are transmitted through, and 
largely dissipated in the fork blades FB, the fork crown FC, the steering 
tube ST and, in some cases, the rest of the bicycle frame. When the forces 
are transmitted through the fork blades FB to the head tube HT, it will 
deflect to the left, as indicated by the arrow D.sub.HT, and the fork 
crown FC (which is mounted on the steering tube, not shown) turns or 
rotates relative to the head tube HT as indicated by the arrow FC.sub.R. 
So long as the bicycle has a proper trail, i.e., the axis of the head tube 
intersects the road ahead of the road contact point RCP, the head tube 
deflection D.sub.HT will generate a steering impulse which is indicated by 
the arrow SI.sub.S. The subscript S in SI.sub.S identifies this impulse as 
one that is generated because of the spoke configuration of the wheel W. 
When the wheel W is rolling, and the next spoke, i.e., spoke 9 which is 
connected to the right wheel flange F.sub.R, is centered over the RCP (not 
shown), the directions of the vectors or arrows SI.sub.S, FC.sub.R, and 
D.sub.HT are reversed, and the magnitude of D.sub.L is increased to 0.025 
inches while the magnitude of D.sub.R is decreased to 0.010 inches. Modern 
bicycles can accommodate these forces with very little disturbance 
detected by the rider, so long as the spoke count is high enough. In low 
spoke count wheels, such as the fourteen spoker illustrated in FIGS. 10 
and 11, the steering impulses generated due to the conventional spoking 
pattern are very noticeable, although they can generally be tolerated 
except in demanding conditions such as racing with high lean angle 
cornering. In demanding conditions, the steering impulses induced by a low 
spoke count front wheel with a conventional spoking pattern can lift the 
front wheel off the ground in high lean angle turns. 
The situation is different in the case of a rear wheel on an axle which is 
mounted on rear dropouts, because the seat stay and the chain stay do not 
have the flexibility of the fork blades. Consequently, there is little 
vertical axle deflection in the case of a rear wheel. However, the forces 
attributable to conventional spoking, discussed above, in the context of a 
front wheel, cause the rim of a conventionally spoked rear wheel to be 
deflected at the RCP, away from the spoke centered over the RCP at any 
given time during revolution which, in effect, causes the RCP of a 
conventionally spoked rear wheel to trace a sinusoidal pattern on the road 
as a loaded rear wheel rolls along. In the case of the fourteen spoke 
conventional wheel, mounted in a Park truing stand as it would be at the 
rear of a bicycle, with the axle restrained and a one hundred and fifty 
pound load applied, a right departure of the RCP of 0.1 inch was measured 
from the wheel center plane when a left spoke was centered over the RCP 
and a left departure of the RCP of 0.1 inch was measured from the wheel 
center plane when a right spoke was centered over the RCP. This presents a 
problem in the case of high lean angle turns because the force of the rear 
wheel against the road surface is pulsed which can allow the rear wheel to 
lose static friction with the road surface in a worst case high lean angle 
turn scenario. In the context of straight or level riding, the sinusoidal 
tracing of the rear RCP relative to the vehicle line of travel in effect 
means that the rear RCP is shifted, left to right and right to left, of 
the vehicle center of mass which normally lies in the rear wheel center 
plane, with the passage of successive spokes over the rear RCP. This 
repetitive shift of the rear RCP relative to the system center of mass 
causes the entire frame to move left to right and right to left and, to 
the extent that the head tube, as part of the frame, is leaned to the 
right or to the left, a steering pulse is induced to the left or to the 
right, respectively and it is now appreciated that a conventionally spoke 
rear wheel can and does induce steering pulses quite independently of the 
front wheel under all riding conditions. 
The foregoing analyses of the conventionally laced front wheel is based 
upon the ideal condition that all of the spokes in the wheel W are equally 
tensioned. In the real world, rims that are true do not have equally 
tensioned spokes. Instead, one of the spokes will be tighter than the rest 
and it is frequently adjacent to spokes which are in substantially less 
tension. Accordingly, it will be appreciated that, at least once per 
revolution, the horizontal axle deflections in a conventionally spoked 
fourteen spoke front wheel will be substantially greater than those 
reported above. In any case, as a result of the axle deflections and 
associated fork blade deflections under the condition illustrated in FIGS. 
10 and 11, there are steering impulses, indicated by the arrow SI.sub.S in 
FIG. 11, and the impulse generated when the tightest spoke passes over the 
road contact point RCP, is the most substantial. As the speed of wheel 
rotation increases, so too does another steering impulse which is 
generated during rotation of a conventionally spoked front wheel. 
At high rates of rotation, the wheel W develops substantial gyroscopic 
inertia which is proportional to the rate of rotation. The deflections of 
the axle A due to the conventional spoking pattern described above with 
reference to FIGS. 10 and 11, are transmitted to the steering tube and 
ultimately, as a result of fork rake, trail and head tube angle, result in 
cyclic rotational steering impulses seen at the handle bar, at all riding 
speeds. As described previously, the steering bar rotates clockwise and 
counterclockwise, from the view of the rider, with the passage of a left 
spoke and a right spoke, respectively, over the RCP as the wheel rolls 
along under load causing the front of the front wheel to move right and 
left, respectively. At high rates of rotation (not shown), the wheel W of 
FIGS. 10 and 11 develops substantial gyroscopic inertia which is 
proportional to the rate of rotation. The deflections of the axle A, 
described above with reference to FIGS. 10 and 11, translate, at high 
rotational speeds, to rotation of the axle in a substantially horizontal 
plane, about a substantially vertical axis VA, illustrated in FIG. 11, and 
passing through the mid-point of the axle. This rotation of the axle about 
the axis VA is known as precession. This precessional axle movement is in 
the same direction as the steering impulse SI.sub. S described previously 
as attributable to the conventional spoking pattern. In FIG. 11, arrow 
SI.sub.G represents the force generated, at high rotational speeds, as the 
axle dips lower on the right as represented by D.sub.R. Arrow SI.sub.G 
reflects movement of the front F of the wheel W which is due to gyroscopic 
inertia and precession. Arrow SI.sub.S reflects movement of the front F of 
the wheel W due to the conventional spoke pattern induced steering 
impulse. The two movements or impulses SI.sub.S and SI.sub.G are 
substantially in phase and, as a consequence, their net effect on the 
wheel W is cumulative. In the case of the rotating wheel W of FIG. 11, the 
precession motion translates into a second steering impulse, indicated in 
FIG. 11 by the multi-headed arrow SI.sub.G, and that steering impulse is 
in the same direction as the spoke induced steering impulse SI.sub.S. The 
arrow SI.sub.G is multi-headed to reflect its variable magnitude which is 
a function of the disturbing force (relatively constant) and the rate at 
which the wheel is rotating. As the rate of rotation increases, so too 
does the magnitude of the steering impulse SI.sub.G associated with the 
precession motion of the axle/axis. The consequence of the combination of 
the steering impulses SI.sub.S and SI.sub.G at low speeds may be 
tolerable. At higher speeds, however, the magnitude of the SI.sub.G will 
reach a point where, combined with the SI.sub.S, speed shimmy or wobble 
occurs. The precise point or speed at which speed wobble or shimmy is 
induced is affected by the factors listed above in the quotation from 
Bicycling. However, the source of speed wobble or shimmy is the steering 
impulse generated as a consequence of the conventional spoking pattern. At 
certain bicycles speeds or wheel rotation frequencies, an oscillating 
vibration is set up which is fed, on one side by the forces associated 
with axle deflection and precession motion in the wheel and, on the other 
side, by the fork reaction forces which tend to return the axle to an 
undeflected position. As noted above, the magnitude of the precession 
motion increases with speed and there is a speed or speed within the 
dynamic bicycle system at which the magnitude of the vibrations increases 
beyond the capacity of the mass damper constituting the rider, the fork 
and other frame members to dampen the vibration and the result is the well 
documented speed wobble or shimmy where the entire bicycle begins 
vibrating wildly. This condition has mystified experts in the bicycle 
field, although they have come to recognize some of the factors, listed 
above, which influence the onset of speed wobble or shimmy. These 
observations are consistent with the explanation above, but so far, no one 
else has recognized that the conventional spoking pattern is the source of 
this evil and dangerous phenomenon. 
The bicycle of the present invention solves the problem of speed wobble or 
shimmy by eliminating its source, namely, the steering impulses generated 
as a result of the conventional pattern of spoking in wheels. Without the 
forces generated when the axles deflect, there would be no exciting 
impulses to trigger the spoke induced steering impulses and the associated 
precession and rocking motions and, thus, no energy to drive the vibration 
at levels which exceed the capacity of the loaded bicycle system (which 
acts as a mass damper) to absorb them. 
Referring now to FIG. 12, a bicycle according to the present invention is 
indicated generally at 100. The bicycle 100 comprises a front wheel 102 
which is an eighteen spoke wheel 10 illustrated in FIGS. 1 and 2. The 
wheel 102 includes hub flanges 104 (one is visible in FIG. 11) which are 
supported on a hub 106 for rotation about an axle 108 which is mounted in 
the ends 110 of a fork 112. The fork 112 comprises fork blades 114 
supported in a fork crown 116 which, in turn, is supported in a head tube 
118. The bicycle further comprises a top tube 120, a seat tube 122, a down 
tube 124, lugs 126, a bottom bracket 128, chain stays 130 and seat stays 
132. A rear wheel 134, corresponding with the wheel 40 shown in FIGS. 3 
and 4, is mounted for rotation about an axle 136 which is supported in 
dropouts 138. Although it is preferred that the rear wheel correspond with 
the wheel 40 (FIGS. 3 and 4), a bicycle according to the present invention 
may include a conventional rear wheel so long as it includes a front wheel 
with paired spoking according to the present invention. As a consequence, 
the bicycle 100 will not be susceptible to speed wobble or shimmy 
originating in the front wheel. In another embodiment, the bicycle 
comprises a front wheel and the rear wheel 134 and, in this embodiment, 
the sinusoidal tracking of the rear wheel is eliminated. In the most 
preferred embodiment, the bicycle comprises the front wheel 102 and the 
rear wheel 134. 
It is believed that the foregoing description demonstrates that a wheel 
with a given spoke count, according to the present invention, has better 
stability than conventionally laced wheels of the given number of spokes 
and, in most cases, better stability than conventionally laced wheels 
having more than the given number of spokes. It has been further 
demonstrated that a bicycle including a front wheel according to the 
present invention is not susceptible to the age old problem of speed 
shimmy or wobble. 
It will be appreciated that the invention is not limited to the foregoing 
detailed description but, rather, has broad applications in the field of 
wheels. For example, Tioga.RTM. has introduced a wheel in which 
conventional spokes are replaced with a Kevlar.RTM. lacing which provides 
tension between the rim and hub in what is believed to be a conventional 
fashion, that is, lacing is connected to the rim at points which are 
evenly, circumferentially spaced, at each point, tension is either applied 
from the left side of the hub or the right side of the hub as opposed to, 
in the case of the present invention, the case where pairs or groups of 
pairs of spokes or other tensioning members apply tension from the left 
and right side of the hub to points which are closer together than the 
distance between the groups or pairs of clusters, or at points which are 
circumferentially coincident, so that unresolved side or lateral forces 
are reduced, by comparison with a wheel laced according to the prior art, 
or eliminated.