Motorcycle fork adapter

A motorcycle neck adapter comprising a main body formed of a single piece of metal, and a cavity socket formed on an aft end of the main body. The cavity socket is configured to receive an existing motorcycle neck. An upper set screw opening is formed on a top surface of the main body. An upper set screw is installed into the upper set screw opening. The upper set screw is configured to engage an existing motorcycle neck at an existing motorcycle steering neck top opening. The upper set screw is secured to the upper set screw opening by a threaded connection. A lower set screw opening is formed on a bottom surface of the main body. A lower set screw is installed into the lower set screw opening.

FIELD OF THE INVENTION

The present invention is in the field of motorcycle fork adapters.

DISCUSSION OF RELATED ART

When customizing a motorcycle front end, the front fork rake angle and other metrics need to be modified to receive a new motorcycle fork. In particular, when adapting to a larger front wheel clearance geometry require moving the neck upwards to clear the wheel. A variety of different motor cycle fork extensions have been implemented, such as U.S. Pat. No. 3,556,557 entitled Motorcycle Fork Extension by inventor R. E. Blair III patented Jan. 19, 1971, the disclosure of which is incorporated herein by reference. Inventor Dehnisch in U.S. Pat. No. 4,565,384 issued Jan. 21, 1986 entitled Motorcycle Fork Tree teaches an adjustable motorcycle fork tree. Additionally, Mrdeza in U.S. Pat. No. 7,438,306 issued Oct. 21, 2008, entitled Motorcycle Rake And Trail Adjuster, the disclosure of which is incorporated herein by reference, provides a motorcycle fork rake extension kit with a securing bolt for clamping the extension portion to the stock portion. The Mrdeza reference requires two separate plates to be clamped to the frame by a through bolt.

A common problem with the prior art bolt on neck rake altering systems is that they lack adequate structural strength. This lack of structural strength has led many within the motorcycle community to avoid these bolt on kits. Instead they would rather go through the tedious and time consuming process of cutting the neck off and welding a new one in place.

SUMMARY OF THE INVENTION

A motorcycle neck adapter comprising a main body formed of a single piece of metal, and a cavity socket formed on an aft end of the main body. The cavity socket is configured to receive an existing motorcycle neck. An upper set screw opening is formed on a top surface of the main body. An upper set screw is installed into the upper set screw opening. The upper set screw is configured to engage an existing motorcycle neck at an existing motorcycle steering neck top opening. The upper set screw is secured to the upper set screw opening by a threaded connection. A lower set screw opening is formed on a bottom surface of the main body. A lower set screw is installed into the lower set screw opening. The lower set screw is configured to engage an existing motorcycle neck at an existing motorcycle steering neck bottom opening. The lower set screw is secured to the lower set screw opening by a threaded connection. An upper bearing mount is formed on the top surface of the main body for receiving an upper tree and a lower bearing mount formed on the bottom surface of the main body for receiving a lower tree in a triple tree configuration.

The one piece construction is possible because the use of set screws to push against the stock neck, as opposed to a central bolt that clamps the neck together. This allows for a very rigid connection.

Optionally, the motorcycle neck adapter can also include a pair of side bolt holes formed through a main body left side and a main body right side of the motorcycle neck adapter to secure the motorcycle neck adapter to an existing motorcycle frame. An upper circlip can be installed into a circlip groove upper formed on the upper set screw opening to retain the upper set screw and a lower circlip can be installed into a circlip groove lower formed on the lower set screw opening to retain the lower set screw. The upper set screw can be recessed into the upper set screw opening, and the lower set screw can be recessed into the lower set screw opening. A steering lock boss can be formed on the main body. A fairing mount can be formed on a front portion of the main body. The frame lock opening can be formed as a first slot. An outer frame opening formed as a second slot.

The following call out list of elements can be a useful guide in referencing the elements of the drawings.111Standard Motorcycle Steering Neck2Neck Adapter13Body Cap33Steering Stem28Lower Triple Tree27Upper Triple Tree39Circlip Upper63Lock Nut67Side Mount Bolt71First Slot72Second Slot73Upper Side Mount Bolt Opening (Side Bolthole)74Lower Side Mount Bolt Opening (Side Bolthole)75Upper Edge76Front Edge77Lower Edge85Upper Bearing86Bearing Race Upper101Upper Steering Neck Socket102Lower Steering Neck Socket201Upper Set Screw202Lower Set Screw61Top Nut631Side Mount Bolt671Side Mount Nut851Lower Bearing861Lower Bearing Race391Lower Circlip239Circlip Groove Upper267Side Bolt Hole268Additional Side Bolt Hole227Opening For Lower Tree233Opening For Steering Tube286Opening For Upper Bearing Race (Upper Bearing Mount)2111Stock Neck Opening (Cavity Socket)2112Outer Frame Stock Bike Opening2113Frame Lock Opening2201Upper Set Screw Socket (Upper Set Screw Opening)2202Lower Set Screw Socket (Lower Set Screw Opening)2391Lower Circlip Opening2201Upper Set Screw Thread2301Fairing Mount2302Fairing Mount Hole2861Lower Bearing Opening (Lower Bearing Mount)

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A standard motorcycle typically has a front wheel and a rear wheel. The front wheel is retained to the motorcycle by the front fork. The steering neck111of the motorcycle in turn retains the front fork assembly. The neck needs to be modified so that a new fork tree can be implemented. The position of the fork is modified by the present invention by a neck adapter that moves the position of the fork assembly from the old steering neck location to a new location. The stock motorcycle typically has a steering axis that has a forward angle. The first step for modifying the stock motorcycle is to remove the trees, steering bearing, fork and wheel from the stock motorcycle. As shown inFIG. 2. The new neck adapter2is then installed to the stock neck111, as shown inFIG. 3. The neck adapter2is secured with set screws201and202. The set screws are installed into the old steering head, as shown inFIGS. 4 and 5.

The upper set screw201fits into the upper steering neck socket101of the stock motorcycle neck111. The lower set screw202fits into the lower steering neck socket102of the stock motorcycle. The neck adapter2has a slot that allows it to fit onto the stock motorcycle frame.2111

The neck adapter2is preferably a single block of aluminum billet that has been cut to form a main body of the neck adapter. By forming the neck adapter from a single structure, the possibility of misalignment is greatly reduced. The main body of the neck adapter has a steering tube233with a new upper fork bearing race socket286and a new lower bearing race socket2861. After the adapter is fitted over the neck, and the set screws201and202are secured into place, the top nut (61) secures the steering stem33and upper triple tree of the new fork and the upper bearing85is retained within an upper bearing race86such that the upper bearing85and the upper bearing race86is installed into the new upper neck socket286. Similarly, the new lower neck socket2861receives a lower bearing race861which retains a lower bearing851. The steering stem33connects the lower triple tree28to the upper triple tree27. The steering stem33has an upper end that is ready to receive the top nut61, as shown inFIG. 6.

The neck adapter2also has a first slot71and second slot72cut horizontally across the body of the neck adapter. The neck adapter can be cut from billet aluminum. The first slot71can be formed as an outer frame stock bike opening2112, and the second slot72can be formed as a frame lock opening2113. Alternatively, the first slot71can be formed as the frame lock opening2113, and the second slot72can be formed as an outer frame stock bike opening2112.

The upper set screw socket2201and lower set screw socket2202preferably include circumferential grooves (239and2391) to respectively receive an upper circlip39and a lower circlip391. These circlips prevent vibration driven or accidental backing out of the set screws.

One or more side mount bolts may be used to further secure the assembly to the motorcycle frame. The first side mount bolt67is retained by the first lock nut63and the second side mount bolt671is retained by the second lock nut631. The first side mount bolt67, and the second side mount bolt671respectively fit into the first side mount bolt opening267and the second side mount bolt opening268. The stock motorcycle frame may have openings that the first side mount bolt67and the second side mount bolt671can be mounted to. The upper side mount bolt73can be formed as the first mount bolt opening267and the lower side mount bolt74can be formed as second side mount bolt opening268.

The second side mount bolt opening268is below the second slot72. The second slot72has an upper edge75, a front edge76, and a lower edge77. The second side mount bolt opening268is preferably the same size as the first side mount bolt opening267. The second slot72is preferably cut into the body of the neck adapter up to at least the old axis of rotation when seen from a side view such as inFIG. 10. The upper set screw and the lower set screw can be formed as socket caps for capping the old upper and lower sockets. The upper and lower set screws can be retained by circlips.

The neck adapter (2) has an opening to fit the stock neck of the motorcycle111. This opening which can be called the stock neck opening2111. The unit may also have an outer frame opening2112which can be formed as the second slot. Similarly, the frame lock opening2113formed on the new neck can also be formed as an additional slot which can be a first slot. The lower bearing opening2861opposes the upper bearing opening286. Clearance for the lower triple tree28may be provided by forming the neck adapter at227. The position and shapes of the openings2111,2112,2113are dictated by the shape of the stock motorcycle neck. The openings allow the neck adapter to be easily mounted to the standard motorcycle. Different motorcycles may require different openings to allow fitment of the neck adapter2.

The fairing mount2302has one or more a fairing mount holes2301for mounting the fairing to the fairing mount. The fairing mount2302is integrally formed with the steering tube. The fairing mount2301can be integrally formed with the steering tube.

The neck adapter2is preferably made of a single piece cut from billet aluminum and then held in place by the two large set screws201and202. Interior curves can be formed on the inside portion of the neck adapter2so that the alternate interior curves match the neck. The set screws201and202, fit into the bearing race so that the stock bearings need not be removed. The neck adapter2alters the position of the neck to increase or decrease rake, or to move the neck up or down, or to move the neck forward. The neck adapter2may accomplish any one or a several of these alterations to the position of the neck. The circlips prevent the complete extraction or dislodgment of the set screws201and202. Additional stability is provided by the side bolts that tie into the frame. A cavity is formed on the aft end of the one-piece neck adapter2. The cavity has a shape that is contoured to engage the neck of a stock motorcycle.