Note: Descriptions are shown in the official language in which they were submitted.
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TITLE: Motorcycle Conversion Kit
FIELD OF THE INVENTION:
This invention relates to motorcycle conversion kits for adding
auxiliary wheels to motorcycles, and more particularly is concerned with
kits for converting motorcycles from two to four wheels. The kit being
easily installed and removed without major modification to the motorcycle.
BACKGROUND OF THE INVENTION:
Modern full sized touring motorcycles have become increasingly
heavy over the past years. This is in part due to the desire from the
consumer for larger, more powerful machines having larger displacement
engines but also as a result of the increasing number of luxury amenities
found on modern motorcycles which can include: navigation systems,
climate control systems, communication systems, entertainment systems
and expansive luggage compartments. With this added weight comes the
inevitable condition of motorcycles becoming top heavy and very
cumbersome at slower speeds.
The problem of slow speed stability is also encountered by
inexperienced motorcyclists who are prone to spills when they are learning
to ride.
This problem is solved in part by prior art conversion kits, the most
relevant is US Patent 5,853,057 to Mullins, which teaches a conversion kit
having a generally U-Shaped frame member to which are mounted two
auxiliary wheels. The frame member mounts to the motorcycle frame by a
pivotal connection at a front end and at a rear end the frame member is
rigidly connected to the motorcycle's swing arm. With such an
arrangement, the three rear wheels are forced to move in unison. This has
the disadvantage that if only one of the wheels encounters an obstacle,
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such as a bump, while moving at speed, the other two wheels are urged to
move with the first wheel causing a potentially unstable and dangerous
condition which could lead to an accident. Also, when one attempts to
corner with a motorcycle equipped with the Mullins' kit, it is impossible to
tilt the motorcycle as one normally would to better negotiate the turn, which
leads to an awkward feeling for the rider.
Other motorcycle conversion kits known in the art are provided for
converting motorcycles into trikes or three wheeled machines. This
involves extensive modifications of the motorcycle which are sometimes
virtually irreversible. This solution is therefore not satisfactory.
SUMMARY OF THE INVENTION:
Therefore, the main object of the present invention is to provide a
motorcycle conversion kit wherein each of the rear wheels is independently
suspended in order to overcome the aforementioned drawbacks of the
prior art.
Accordingly, there is provided a motorcycle conversion kit
comprising a generally U-shaped frame member having parallel, spaced
apart side members having front and read ends, said side members are
angled towards each other near the front end thereof. Front and rear cross
members extend between the front and rear ends of the side members,
respectively. A rear wheel of the motorcycle being received in a space
between the side members. The frame member is rigidly attached to the
motorcycle frame via quick attachment brackets at the front and rear ends
thereof. An auxiliary wheel is mounted to each of the side members by a
trailing arm suspension member such that the rear wheel of the motorcycle
and each of the auxiliary wheels are in axial alignment and are
independently suspended.
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Each trailing arm suspension member comprising an arm
member having a hole in each end. A pivot shaft extends from a proximal
hole in a first direction, perpendicular to the arm member and a wheel hub
extends from a distal hole in a second direction, perpendicular to the arm
member. The hubs are rotatably mounted on ball bearings and have a
plurality of studs for mounting the auxiliary wheels.
The trailing arm suspension member comprising a housing rigidly
mounted to the side member, the pivot shaft extending inside the housing,
and a compressive material, such a rubber, filling a space between the
housing and the shaft. Said compressive material being adhered to both
the housing and the shaft to resiliently restrain the shaft from rotation
within the housing.
The frame member further comprising adjustment means at the front
end to allow for proper alignment of the auxiliary wheels with respect to the
rear wheel of the motorcycle. The adjustment means comprising a tie-rod
having a threaded portion received in a forward most extremity of each of
the frame side members and a nut associated therewith to lock the tie-rods
in position once they are properly adjusted. The tie-rods also having an
eyelet at one end to receive a pair of mounting bolts therethrough.
The front quick attachment bracket comprising a tubular member
extending between the tie-rods. Said bracket further comprising a piece of
angle iron welded to the tubular member which extends parallel thereto.
The angle iron having a pair of holes at each end for receiving a pair of U-
bolts. The front quick attachment bracket is mounted to the motorcycle
frame directly beneath the motor by means of the U-bolts.
The pair of mounting bolts are used to secure the front end of the
frame member to the front quick attachment bracket. Each of the
mounting bolts extending through a tie-rod eyelet and into the tubular
member.
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A pair of spaced apart lugs extend vertically from the rear cross
member. Each lug having a vertical slot therein to allow for vertical
adjustment of the rear end of the frame member.
The rear quick attachment brackets consisting of a pair of vertically
extending planar members. Each rear quick attachment bracket extending
between a rear portion of the motorcycle frame and a respective lug. Bolts
are used to secure the rear quick attachment brackets in place.
Another aspect of the present invention is to provide a trailer hitch
mounted to the rear cross member.
A further aspect of the present invention is to provide a fender
covering each wheel to protect the rider and other motorists for debris and
water which may be expelled from the rotating wheels. Each fender may
also have signal lights for improved visibility and security.
In an alternate embodiment, the lugs may be located on the frame
side members instead of on the rear cross member to suit a particular
application, such as smaller sized motorcycles.
Optionally, the motorcycle conversion kit may be provided with a
custom color scheme to match that of the motorcycle on which it will be
installed.
BRIEF DESCRIPTION OF THE DRAWINGS:
Figure 1 is an perspective view of the motorcycle conversion kit.
Figure 2 is a top view of the motorcycle conversion kit.
Figure 3 is a close-up perspective view of a rear portion of the motorcycle
conversion kit with one wheel removed for clarity.
Figure 4 is a close-up perspective view of the trailing arm suspension
member.
Figure 5 is a close-up perspective view of a front portion of the motorcycle
conversion kit
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Figure 6 is a close-up perspective view of the front attachment means.
DETAILED DESCRIPTION OF A PREFERED EMBODIEMENT:
As shown in Figures 1 and 2, the motorcycle conversion kit
comprises a one-piece tubular U-shaped frame member 1 which is bent to
suit a particular application. The U-shaped frame member having parallel,
spaced apart side members with front and read ends. Said side members
are angled towards each other near the front end thereof. A rear cross
member extend between the rear ends of the side members. Longitudinal
brace bars 2 are welded to the side members to provide additional rigidity.
Lateral brace bars 3 and 4 are welded in place near the front and rear
ends to complete the basic frame structure. Footboards 5 are welded the
frame covering the opening between the side members and the
longitudinal brace bars 2.
A pair of spaced apart lugs 9 extend vertically from the lateral brace
bar 3. Each lug having a vertical slot therein (not shown) to allow for
vertical adjustment of the rear end of the frame member.
Rear quick attachment brackets 10 are provided for mounting the
rear of the frame to the motorcycle. Each rear quick attachment bracket
extending between a rear portion of the motorcycle frame and a respective
lug 9. Fasteners 11 are used to secure the rear quick attachment brackets
in place.
As shown in Figures 5 and 6, the front end of the frame is provided
with adjustment means comprising a pair of tie-rods 20 threadably
received in the front ends of the frame member 1. A pair of nuts 21 allow
the tie-rods to be locked into position once the correct alignment is
obtained.
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The front end of the frame member is attached to the motorcycle via
a front quick attachment bracket. The front quick attachment bracket
having a tubular member 23 and an angled member 24 which are welded
together. The angled member 24 having a pair of holes drilled in each end
thereof for receiving a pair of U-bolts 25 which are used to fasten the
motorcycle frame to the angled member. A pair of mounting bolts 22 are
used to mount the tie-rods 20 to the front quick attachment bracket.
A hitch plate 6 is welded to the rear cross member at a rear
extremity thereof. The hitch plate is provided with a hitch ball 7 and a pair
of holes 8 for securing a safety chain (not shown).
Now turning to Figures 3 and 4, each wheel 19 is mounted to the
frame via a trailing arm suspension member. Each trailing arm suspension
member comprising an arm member 16 having a hole in each end. A shaft
15 extends from the proximal hole in a first direction and a wheel hub 17
extends from the distal hole in a second direction. The hubs 17 are
rotatably mounted on ball bearings (not shown) and have a plurality of
studs 18 for mounting the wheels 19.
Each trailing arm suspension member further comprising a housing
having upper and lower members 12 and 13, a compressive material 14,
such as rubber, filling a space between the upper and lower members and
the shaft 15. Said compressive material being adhered to both the upper
and lower members and the shaft to resiliently restrain the shaft from
rotation within the housing. The housing is rigidly mounted to the side
member either by welding or by suitable fasteners.
Once the motorcycle conversion kit has been installed and adjusted
to the motorcycle it can be easily removed simply by removing the
fasteners 11 and mounting bolts 22 whereby releasing the frame member
from the quick attachment brackets. Installation is reverse of removal.
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The quick attachment brackets can be left on the motorcycle without them
interfering with the normal use of the motorcycle as a two wheeled vehicle.
These and other modifications will be readily appreciated from the
foregoing without departing from the scope and spirit of the invention and
applicant intends to be bound only by the claims herein.
