The Crow's Foot lacing is a pattern that is a little different from a
normal cross pattern. It is based on three spokes being used to form a set,
unlike two spokes in conventional crossed lacing patterns. The Crow's Foot
pattern can be used to make your bike a little unique, and builds very
strong wheels. It is called a Crow's Foot because Crow's have three toes on
the front of their feet. I guess it could have been called the 'Chicken's
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The Crow's Foot lacing pattern was popular in the '50's, and gives a wheel
the qualities of both radial and crossing patterns. The three spokes of a
set have a center spoke that is radially laced, with the outer two spokes
crossing each other and the radial spoke. The figure to the right is of one
set of the three spokes in a Crow's Foot pattern (all of the figures in this
chapter show the spokes of only one side of the wheel for clarity, looking
from the outside of the hub).
The radial spokes give the wheel high lateral strength and the crossing
spokes give the wheel torque transfer capabilities. The ride quality is
stiffer than a typical crossed wheel, but not as stiff has an all radial
wheel. This pattern can be used on both front and rear wheels, and it has
been my perception that this lacing holds true better than standard cross
lacing's. From my experience with the Crow's Foot pattern, I have come to
the conclusion that it's overall strength is greater than the sum of the
parts. The two crossing spokes add qualities to the radial spoke, and the
radial spoke adds qualities to the crossing spokes. The sum is one very
strong and dependable wheel.
For multi-speed rear wheels, I have found that a mixed lacing made with a
Crow's Foot pattern on the drive side and a 2-cross on the non drive side
makes for the strongest rear wheels I have ever ridden. A rear wheel made
with a half Crow's Foot mixed lacing has very high drive side lateral
strength and very good torque transfer characteristics. More about this
lacing is discussed in the
STRONG REAR WHEEL LACING chapter.
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The Crow's Foot can be made with two basic patterns, depending on the length
of the crossing spokes. One way is where all three spokes are anchored at
three hub holes right next to each other, the figure above is of this style
of lacing. The other way is to have the outer two spokes of a set cross with
an outer spoke of the sets next door, the figure to the right is of one set
of spokes laced like this.
The only drawback to the Crow's Foot pattern is that it has to be made
with hubs and rims that have spoke holes that are a multiple of 6. This
leaves common hub and rim sets with 36 or 48 spokes. For 48 spoke tandem
wheels a Crow's Foot pattern would be excellent. There is more information
about 48 spoke Crow' Foot patterns at the bottom of this chapter. It is
possible to lace with a hybrid Crows Foot pattern on wheels that don't have
spokes in multiples of 6, like a 32 spoke wheel. I will explain a 32 spoke
hybrid Crow's Foot after discussing a 36 spoke Crow's Foot laced wheel. If
you are working on a vintage high-wheeler, the Crow's Foot pattern could be
an interesting way to lace it's wheel.
The pattern can be laced with hubs and rims with spoke holes that are a
multiple of six, three for a side, but since hubs and rims are made for
standard cross lacing patterns based on two spokes, they are usually
available with spoke holes that are incremented by four, i.e. 28, 32, and
36. They don't make any standard 30 hole hubs and rims. If you bought blanks
and had them custom drilled it would be possible to lace a 30 or 42 hole hub
and rim set with a standard Crow's Foot pattern. I have heard of a five
spoke set Crow's Foot pattern, this pattern could build a 40 spoke wheel. It
is described in the
CUSTOM LACING PATTERNS chapter.
The middle spoke length is determined with the formula for radial lacing.
If you make each set using three holes right next to each other on the hub,
the crossing spoke length is determined by using the values for a 2-cross
lacing. For making sets that have the crossing spokes anchored to the
second hub hole away from the radial spoke, in which case they would cross
with the spoke sets next to them, you would use the values for a 3-cross
lacing to determine the length. One third of the spokes are the radial
length and two thirds are the crossing length. The radial spoke should not
be greased like in an all radial wheel.
If you use the method with all of the spokes of a set right next to each
other, using '2-cross' spokes, the wheels can be laced with all of the
spokes either on the inside or the outside of the hub flange. It would be
possible to mix them anyway you wanted, but I would recommend keeping to a
pattern with all of the groups exactly alike. The wheel will be easier to
build, look the best, handle the stresses the wheel sees better, and give
the wheel a static balance which enhances the reliability.
It has been my experience that if you lace with '2-cross' spokes it is
easiest with the crossing spokes coming off the same side of the flange. It
is possible to alternate which side of the flange they come off of, but this
results in the spoke crossing being very close to the flange which causes
sharp bend angles on the spokes. These sharp bends don't cause any problems
with the spokes so it can be done, if you wish. The figure below shows a 36
spoke hub and a partial section of the rim laced like this.