Restoring History: 1975 Honda GL1000 Gold Wing
1975 Honda GL1000 Gold Wing
Engine: 999cc liquid-cooled SOHC horizontally opposed four, 72mm x 61.4mm bore and stroke, 9.2:1 compression ratio, 80hp @ 7,500rpm
Top speed: 129mph (period test/production bike)
Carburetion: Four 32mm Keihin CV
Transmission: 5-speed, shaft final drive
Weight (wet): 650lb (295kg)
Seat height: 31.6in (802.6mm)
Fuel capacity/MPG: 4.2gal (19ltr)/41mpg (avg.)
Price then/now: $2,895/$6,000-$10,000
Sometime around June or July 1974, after two years of development, clay mock-ups, rigorous engineering and conceptual designs, Honda Project 371 was ready to move to the final stages, with 10 prototype units to be assembled. Honda Motor Co.’s monumental endeavor to build a performance-oriented grand touring motorcycle was about to reach fruition with the GL1000.
In the same way the 1969 CB750 Four was a benchmark motorcycle, Honda wanted its new grand tourer to be the same, a motorcycle of firsts. The new bike would be Honda’s first water-cooled motorcycle. It would be Honda’s first horizontally opposed engine, a design chosen for its smoothness and inherent low center of gravity. And unlike any other horizontally opposed motorcycle engine, it would use overhead camshafts.
In the early stages of design, a 6-cylinder was initially prototyped before project leader Toshio Nozue settled on a 999cc four, with final drive to the rear wheel by shaft. The new engine required a new chassis, and it presented Honda engineers with a number of design hurdles. For one, the engine’s four individual constant velocity carburetors (repurposed from Honda’s 1968-1972 N600 automobile) were placed on top of the engine. That led to the actual fuel tank being located under the seat (further aiding a low center of gravity), with the air filter housing assembly, coolant recovery system, major electrical components and a detachable kickstarter housed in a faux gas tank, with openable panels for access. Fuel was supplied by a mechanical pump driven by the right camshaft.
Introduced in late 1974, the GL1000 was an immediate hit. “If Honda is going to sell a motorcycle for $3,000, then by all that’s holy it’s going to be worth it,” Cycle said in its 12-page April 1975 review, which lauded the GL as a “brilliantly focused” touring machine that was also Superbike fast. How fast? At the time, it was bested in acceleration only by the 993cc Kawasaki Z1, running the quarter-mile in 12.92 seconds at 104.52mph versus the Z1’s 12.37 seconds at 107.39mph.
The restoration of GL1-1000002
Few people know more about the GL1000 story than Pete Boody and his daughter and business partner, Chris Gray, at Pistol Pete’s GL1000 Goldwing Services in Oliver Springs, Tennessee. As the name implies, their company focuses on the GL1000, and after 40 years researching and working on the model, they’ve learned a thing or two.
“The GL1000 prototype featured here is what we’ve found in our research to be one of two units Honda donated to a college to be used for engine mechanics classes for their students,” Pete says. “The instructor was able to get American Honda Motor Co. to donate them, and for years it was the center of their training until newer models were obtained. The instructor negotiated the donation. He had acquired previous motorcycles and was able to obtain additional units as time went on,” Pete adds.
According to Pete, said instructor acquired a complete or nearly complete GL1000 along with a partial machine with drivetrain and other miscellaneous pieces, including various prototype side covers. The engines were utilized for instructional purposes, disassembled and re-assembled by students hundreds of times. When they were replaced by newer engines, the remaining parts were placed in a storage unit owned by the instructor. They remained there for the next 30-plus years, until the instructor passed away. The current owner bought the contents of the storage unit from the instructor’s widow.
“Mid-year 2011, we received an email from a gentleman who claimed he owned GL1000 serial number GL1-1000002,” Pete recalls. “He was interested in having us restore his newfound treasure, and included in the request were several pictures of his find. The pictures showed the frame, engine cases and an assortment of boxes overflowing with hundreds of parts. The pictures clearly identified the serial numbers of the frame (GL1-1000002), as well as the right engine case (GL1E-1000002). At this point it was very evident that he owned major components and parts of the second GL1000 to be assembled by Honda in Japan.”
Excited, Pete agreed to take on the restoration, but after a few more emails the owner told him that for economic reasons he’d decided to have the restoration done locally. “Our obvious disappointment was tendered by our understanding his frugality,” Pete says. The bike was “restored,” and in 2014 it was offered at Mecum Auction’s annual Las Vegas sale. The owner set a five figure reserve, and when it failed to sell he took it home.
Pete owns two significant GL1000 units, GL1-1000040, manufactured in December 1974, and GL1-1000104, manufactured in January 1975. He was already conducting his own research on the GL’s development, but that research kicked into high gear with the discovery of GL 0002.
“Our research led us to find that as many as 11 GL units were made previous to Honda reporting that the  parts/service manuals began with serial number GL1-1000012,” Pete says. “Our research concluded that those manufactured in December 1974 ended with a serial number around GL1-1000049. This was augmented by locating possibly the first production unit, made in January 1975, GL1-1000051. While not 100 percent conclusive, it is relatively significant, and means that as many as 37-38 pre-production units were made in December 1974 before the first production unit in January 1975.”
That raised two questions in Pete’s mind: Where was serial number GL1-1000011, which had engine number GL-1000-000014 (these numbers are cited in the 1975 service manual), and was there a separation in the timeline of the 38 or so made in December 1974 and the beginning of those that were made in January 1975?
“Some say my findings are conjecture, or perhaps speculative at best,” Pete says. “However, if you apply some possible Honda logic to these issues, you may feel as I do. For example, GL1-1000011, with engine number, 0014, may have been a transitional unit between the last prototype 0010 and the first pre-production unit 0012. There are 100-plus external differences between the prototype units and the pre-production units. Of these, most were engineering differences and assembly line improvements.” Pete thinks 0011 could have had some or maybe all of those differences added to it to demonstrate the quality and ease of assembly getting the production line started up. “I believe 0011 was another handmade unit assembled between July and December 1974 just for that purpose,” Pete says.
Pete says that with few exceptions, of the approximately 38 pre-production GL1000s made in December 1974, most were used for Honda engineering testing, advertising and dealer demonstrations, and magazine testing. “The restrictions placed on publications were few, and they were urged to test them as they saw fit,” Pete says. “Honda engineers usually accompanied the units for this phase, and were told that at the end of their evaluations the units would be dismantled and inspected,” as was the case with the GL1000 tested by Cycle for its April 1975 review.
A fair assumption would be that those bikes were eventually destroyed. Pete thinks it’s possible a few might have been stress tested for endurance. Those too would probably have been destroyed. Pete says that a remaining few, perhaps 10, were given to Honda representatives for public demonstrations at dealerships. “A Honda representative would take Gold Wings to dealers and show them to prospective customers,” Pete says. “Later on, they could be turned in to a dealer and sold as used units.” Pete says that two of these, 0040 and 0027, were spared because of this. In his ongoing research, he has so far found two pre-production bikes and three prototypes.
In 2012, Pete was contacted by Peter Rakestrow, the archivist for the Goldwing Owners Group of Great Britain. “He sent us his research on the GL1000,” Pete says, “as well as over 40 digital pictures of the GL1000 in the Neckarsulm Museum in Germany, GL1-1000007.” That was a turning point, because with that information added to what Pete had already learned, he decided to see if GL1-1000002 might yet be available to restore.
In November of 2014, Pete contacted 0002’s owner to see if he would let them perform a correct restoration based on their research. The owner agreed, and on Feb. 2, 2015, GL1-1000002, engine number GL1E-1000002, arrived at Pistol Pete’s in Tennessee.
A month before the bike arrived, Pete received five large cartons of parts for 0002 and, as it turned out, many production parts. “It took us two days to go through each parts box,” Pete says, “and when I reached the last large carton, I got the best surprise of my life. Inside was a complete set of prototype body parts that were painted gray, with black splatter paint sprayed on in spurts.” Carefully removing sections of gray paint revealed that the complete set was actually Sulfur Yellow, a color not offered until the second year of production, 1976. More interesting yet, when 0002 finally arrived, its side covers and radiator covers were found to be production parts. “It appeared we had the only Sulfur Yellow prototype GL1000,” Pete says, and with that the decision was made to paint the bike Sulfur Yellow.
One of Pete’s first tasks was to do a complete inventory of the prototype parts, then determine what was missing, something they could do thanks to the photos Rakestrow had sent. “Because of the magnificent close-up details of the pictures, we were able to not only see what we needed, but to calculate the measurements of missing parts,” Pete says.
Using Rakestrow’s photos, and photos in the 1975 owner’s and service manuals, Pete was able to ascertain how the prototype’s N600-sourced carburetor set was made, and what the parts looked like. “The carburetors were a small assembly that we had to back-engineer in order to recreate the authentically accurate parts,” Pete says, noting that in all they had to recreate nearly 70 individual pieces and parts. Many times some of them had to be made more than once. “The water pump cover had to be made twice as the lower radiator hose connection was at the wrong angle to couple to the radiator. We think the resulting motorcycle is a nearly perfect duplication of the original.”
Finally, during the first week of June 2015, GL1-1000002 was ready for its first test ride. With the original speedometer still showing a very low 144 actual miles, Pete set off from his shop for the short ride across the North Carolina border to Deals Gap and the Tail of the Dragon, an 11-mile stretch of US 129 famous for its 318 curves. That’s hardly the place you’d think someone would take an irreplaceable motorcycle for its shakedown ride, but for Pete, it made perfect sense. “I have traveled this particular route more than 100 times, and I know the road very well,” Pete says, adding proudly, “Plus, I wanted to expose her to fellow bikers and let them know what we had. I wanted to let folks know just how cool this bike was and its contribution to Gold Wing history.”
At the end of June, Pete took the bike to Wauseon, Ohio, for the AMCA National Meet and bike show. There, the bike scored 99.25 out of a possible 100 points, effectively a perfect score as it’s considered impossible to “perfectly” restore a bike to factory. “That made all of our efforts worthy of this great machine,” Pete says with great satisfaction. “It’s been our pleasure to bring this grand prototype Honda GL1000 back to her former self.” MC
The prototypes: Defining the details
By definition, a prototype unit is produced to show the public what a new concept or design is to look like. It is carefully made to almost exactly emulate the next phases of production in appearance and innovation. Following the prototype phase are pre-production bikes.
The colors selected for the 10 prototypes were Candy Antares Red, Candy Blue Green and Sulfur Yellow. I believe that six of the 10 were Candy Antares Red, three were Candy Blue Green and one, GL1-1000002, was yellow. I think they painted more of them Antares Red because of that color’s recognizable look and because it is more photogenic than the other two. With exposed body parts, only the red units were used in pictures taken for the owner’s manuals and the later published GL1000 service manuals that came late in 1975.
Two of the 10 prototypes went to Europe. One was Antares Red, serial number GL1-1000007, and one Candy Blue Green, serial number unknown at this writing. The blue prototype was presented in October 1974 at the Bol d’Or in France and the red prototype was presented in November at the annual motorcycle show in Cologne, Germany. Five prototypes were displayed in September 1974 at the annual Honda dealer convention in Las Vegas, Nevada. We believe those five were serial numbers GL1-1000002 through GL1-1000006, inclusive. One red and one blue unit had Hondaline fairings; the others, one red, one blue and one yellow, were unfaired.
That leaves three prototypes not accounted for, but we know that one red prototype is currently housed in the Honda Collection Hall in Motegi, Japan, and we speculate that bike is serial number GL1-1000001. The remaining two were perhaps used for photography for owner’s and service manuals.
Of the 10 prototype GL1000 units, only three remain in assembled condition. Two are Candy Antares Red and one is Sulfur Yellow, the bike we restored, serial number GL1-1000002. We believe all of the other prototypes were disassembled or destroyed by Honda. — Pete Boody
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