Early Honda SOHC 750 Custom Chopper Cycle 1 Manufacturing Frame

Description

A ONE OF A KIND MOTORCYCLE

This bike is a “chopper” style custom built motorcycle designed by its Dallas owner and assembled by a Montana based motorcycle builder. Every piece except the heads and engine case was bought or built especially for this bike during the two years that it took to complete the project.

The engine was built in Montana while the frame was being built in Oklahoma.

The engine is a 750CB case built to spec using a new lightened crankshaft rods 3mm oversized pistons shaved heads balanced components and oversized valves. It was ported and relieved and bored then fitted with four oversized KeihinCR carbs with polished aluminum billet-turned flared racing intakes. Once the engine build was finished the unpainted engine parts were chromed the case was painted with several coats of silver paint and the heads were painted General Motors red orange with heat resistant ceramic paint. The engine paint has never once discolored cracked or blemished even though the engine has accumulated close to fifty hours time ‘in frame” over the past two years. The engine starts at a touch of the starter then runs with a high-RPM ripping tearing sound much like that of a Formula 1 race car.

The frame design was taken from the soft tail Harley Davidson and cut and assembled from raw stock by well known chopper frame builders Chopper One of Tulsa Oklahoma. Next the frame was fitten with two custom chrome 100 spoke wheels with heavy gold plated nipples built by H D Wheels of Chatsworth California along with a set of different-sized matching custom poured whitewall tires. The heavy duty chrome front forks were then purchased and fitted to the bike for proper rake by Cycle One.

After the bike was moved to Montana the frame was lightened by outsourcing the drilling of a series of carefully spaced matching visually pleasing holes in the swing arm and the outside pivot arm to a mechanical engineering shop. The engine was then aligned to the frame to the builder’s satisfaction and downward curved chrome exhaust pipes with baffles and tips hand made by the builder from a billet of pure brass were installed and adjusted to be free of each other in their brackets. The engine was then “run-in” for approximately 10 hours during which time the tires were inflated to the proper pressures and checked to be sure that they would accommodate the weight of the finished bike at high speed. The frame was drilled in several strategic locations to be used later during the installation of several components. Temporary handlebars were fitted to the frame to allow movement of the bike around the assembly area.

The finish is striking in every regard particularly for its attention to detail. Perhaps the most noticeable facet of the overall appearance is the use of chrome or brass for every fitting and the consistent use of special colors – mineral white and GM redorange -- throughout the bike. For example all of the socket head screws were machined to a taper and then brass plated. All of the fittings were are either brass or chrome.

The battery box was assembled and drilled by the builder who then installed a painted 12 volt maintenance free battery and carefully positioned the assembly on the frame so that it would become a visible part of the bike.

The fuel tank made to spec for the bike by Thompson Choppers. Once it was received it was flushed clean of all construction by-product and custom installation brackets were constructed by the builder. Once cleaned the tank was attached to the frame with temporary brackets and the vintage aircraft fuel cap was cut and fitted to the tank.

The oval shaped oil tank which was part of the engine’s dry sump was designed to be of such a size and shape to fit under the seat and become a highly visible addition to the build. It too was built to spec by Thompson Choppers. A special oil cap was constructed as a design feature from a heavy solid brass radiator cap from an old Ford pickup – then lathe polished to a bright shine. Custom chrome oil lines were installed to both convey oil between the tank and the engine and to connect the two together in a visual manner consistent with the design of the rest of the engine compartment. The whole apparatus was topped off with engine mounted stainless steel heat and pressure gauges.

The fenders which were drawn and built by Milwaukee Steel are strong enough for an adult to sit on either one without damage.

Both brakes are four-piston fully chromed Brembo disc brakes with chrome rotors. The foot rests brake pedal and gear shift are all matched round chrome oversized pegs with alternating milled circles of brass and chrome the same configuration also used on both handlegrips one of which serves as the twist grip throttle. The external gear shift connecting rods are all heavy chrome ground to fit each individual connection

The builder used four orange spark plug wires to match the engine running them from the battery box forward through four tubes of parallel polished copper tubing attached to the underside of the fuel tank to a forward point where they could be “flowered” onto the spark plugs.

The huge 8 inch oversized headlight was metal spun and assembled for the builder. It was centered between the fork tubes several inches down from the handlebars where it’s bright color and eye-catching form visually balances the bike even taking into account its considerable wheelbase.

The last two tasks before sending the bike out for preparation and painting were: the installing of a custom sewm neutral colored leather seat from a seat maker in Denver and the custom assembly by the builder of frame mounted brass seat springs with shocks in a special handmade coil-over configuration designed to highlight the seating arrangement.

The bike was then disassembled and shipped to Ortiz Custom Cycles in Denver a well known custom builder for final smoothing of the welds and metal surfaces and then the application of the magnificent one-off paint job. Before the prep work was even begun Larry Ortiz personally met with the owner and developed the overall painting plan using special paints an imported artist skilled in pinstripe painting and a third artist this one specializing in creating special effects who was tasked with creating a fuel tank pictorial from a National Geographic photo of an exploding sun. The job took 5 months and began with the Ortiz’s artisans hand finishing of the frame with small electric hand grinders and polishers. Once that was done a coat of BMW metallic white paint was applied to the frame fenders and fueltank and the GM red orange color was used on the headlight oil tank several frame members and the taillights. Working simultaneous one artist created the “meteor” which was then overlaid on to the fuel tank while another highly reputed artist prepared several samples of his personal pinstriping from which the selected pattern was applied to the fenders and tank. Without doubt the paint job on the chopper both in design quality originality and application is one of a kind

Once the paint cured the bike was returned to Montana and reassembled and several high points added during the finishing up of the motorcycle.

In order to use indicators that fit with the design of the machine and which would function with the original electric system it was necessary to purchase both a specially built analogue speedometer and a specially built analogue tachometer from a German custom house MotoGadget since they are not unavailable for purchase over the counter. Matched aluminum housings one each containing a speedometer and a tachometeter with matching faces and indicator needles were purchased to house the instruments. The finished gauges were installed on the bike by bolting the speedometer to the left handlebar the tach to the right and then integrating both into the machine with wiring concealed within the frame. It is difficult to overemphasize the quality of this feature. Analogue gauges are no longer in production and the cost to persuade the manufacturer to build two new duplicate instruments was very high. As well it took months of fine adjusting before either instrument would produce reliable consistent output. Needless to say these two beautiful polished one-of-a-kind instruments are worth more than many commercially manufactured motorcycles.

In keeping with the quality and uniqueness of the finish work the temporary handlebars were replaced with oversized bars and risers supplied by Exile Cycle. The drive chains are oversized heavy duty and gold colored to fit the color scheme. The temporary handlebar levers were replaced with new heavy duty ones which are brass plated and machine polished. The taillight is a set of two small coordinated orange painted lights one on each side of the rear fender which lights also double as directional signals. The kickstand is heavy chrome forward swinging and attached to the left side.

The last addition was not the most expensive but may well be the most unique part of the bike is a small rear-facing video camera was installed beneath the seat and connected to a small upward-tilted screen attached between the forks just below the handlebars. Thus – no need for the clutter and obstruction of a pair of rear view mirrors!

The bike carries a full Montana title free of all liens and restrictions issued against Chopper One’s MSO after inspection and approval by a peace officer from the Montana Department of Safety.

This bike comes with free shipping in the lower 48 states.

Also published at eBay.com