The Old Green Honda Four Project
“Quite a few more items were to be found using various internet resources before the project was completed. Mufflers, lights, indicators, wiring loom, dash, mirrors, to name a few,” said Paul.
HAVING previously owned a couple of Honda Fours, and having raced both solo and sidecar versions in Historic Racing, I had a bit of a parts collection hanging around. This included a complete motor plus a hot-rod bottom-end built for racing. So I decided that a bike project would an the ideal way to fill in the time during winter.
Beginning with an ex-road-race frame from a friend, I began by cutting off all of the unwanted brackets and lowering the frame rails under the seat area. One of the requirements was to be able to ride the bike on some of our less-than-perfect back roads, and with a somewhat second-hand rider, the suspension had to stay. So began what was supposed to be a six-month build.
A friend kindly donated the late 1990’s Softail rear, and Sportster front fenders. Some time spent on eBay soon found the required Suzuki GS500E wheels and brakes, along with the 1986 Sportster front-end because it was cheap!
The Sportster forks were fitted to Honda CB750-F2 triple trees, and the wheels were fitted up using custom spacers. A custom stainless-steel nut was even turned for the modified Honda front axle. The Suzuki brake caliper was also modified to fit the fork leg.
Quite a few more items were to be found using various internet resources before the project was completed. Mufflers, lights, indicators, wiring loom, dash, mirrors, to name a few.
A new oil tank was needed to compliment the lowered frame rails and an out-of-date BBQ gas bottle was pressed into service. This had all the gas fitting removed and holes filled before having the necessary oil fittings and filler neck installed. A stainless steel cap and dipstick were fab-ed and a couple of o-rings fitted to keep it sealed. A new cross-member was added to the frame, along with a bracket being added to the rear engine mount plate, to hold the tank in place.
The rear fender is supported by a pair of one-off fabricated stays.
A CB500 swing-arm was used as it was longer and could be modified to take the stay for the brake caliper.
Next was the rear brake master cylinder which was eventually mounted to the inside of the right-hand muffler stay on the frame.
Forward controls are from a mixture of fabricated parts, some recycled Subaru clutch pedals, and go-kart tie-rod ends. Brackets were welded to the frame for them to bolt to.
Handlebars were bent from 7/8-inch stainless tube and mounted in a pair of 1970’s-era Dog Bone risers. The digital speedo sits in a custom fabricated housing mounted with the bars to the top triple tree.
After soaking the wheels in paint thinner to remove the factory finish, they were sanded smooth and polished, along with other alloy items and some of the engine covers. Many of the fabricated items were either chrome-plated or made from stainless-steel and polished.
Mazda-green acrylic lacquer with black lace was applied to the tank and modified fenders by myself.
The seat was formed from a fibreglass base made by covering the frame in masking tape and plastic and laying up the fibreglass over the frame. Paul at Motorcraft Motor Trimmers on Coburg did the trimming.
Starter solenoid and ignition switch housings were fabricated and mounted to the underside of the new frame gusset below the seat, as were the CB900F solid state regulator/rectifier and electronic ignition modules for the CB900F ignition system and the stainless-steel tray housing the fuse-box and other electrical bits.
The motor was built from the best of both motors (which included lots of near new parts) and a new 836 cc piston kit.
Exhaust headers were fabricated from bends and lengths of pipe purchased from a local exhaust shop, terminated by a pair of bored-out Sportster mufflers sourced via eBay.
Finally, rolling out of the shed almost two years later, the bike has been a joy to ride and is regularly chosen over of my 2001 Harley-Davidson Super Glide.
I would like to thank Andrea, my wife, for her patience and help; along with Vince, Adam, Lynne, and all those who offered ideas and provided assistance along the way.
article by Paul Pluckhahn
More amazing Ozbike features to check out:
