By Mark Gardiner
While walking through the motorcycle swap meet at Vintage Motorcycle Days, I suddenly found my eyeballs fixated on an old dirt-tracker hiding within a dimly lit trailer. It was the engine fins that gave it away—Honda®, twin-cylinder.
The bike's owner, Kenny Thomas of Murray, Kentucky, smiled and asked if I wanted to take a closer look. He didn't have to ask twice. "What's interesting about this bike," said Thomas, "is the motor. Check the serial number."
I leaned in close, waiting for my eyes to adjust from the bright summer afternoon to the trailer's gloom. The number read: CL72E 210002.
The CL72 referred to Honda's legendary parallel-twin 250cc motor. Thomas disappeared into his Winnebago and emerged with the Honda parts manual for the motor. He pointed to the first serial number listed in the sequence for the CL. It was the very same number stamped into the cases of this vintage racer, 210002.
Thomas went on to explain that although this bike wasn't Honda's first factory-sponsored flat-tracker, it was built with some back-door support from the factory. As a result, at that time, this particular machine generated considerable interest and publicity for the company, long before Honda's full might was aimed toward winning the Grand National Champion-ship with the legendary RS750.
It turns out the frame was designed and built by Tom Cates, a well-known motorcycle racer who resided around Evansville, Indiana, during the 1950s. Cates went to work for American Honda in 1961, then returned to Evansville in 1992 to work for Honda as a service instructor.
The CL72 was introduced that year, and Cates brought one of the motors—number 210002—back to Indiana, carting it around to various Honda dealership service departments to provide in-service training. "I must have taken that thing apart and put it back together 700 times," Cates recalls.
The Honda 250 twin generated good power, revved freely, and had a growing reputation for reliability, so the motors quickly attracted the attention of racers. Cates felt that given a rolling chassis that kept total weight down to around 200 pounds, the CL72 motor had good potential in Class A short track racing. After about a year of service demonstrations, Honda allowed Cates to install motor number 210002 in a frame of his own design.
Cates welded up a frame that used the same motor mounting points as the CB250 road bike. The steering head and spine of his design are a rather elaborate space frame, tapering back to a rigid, twin-loop rear end. At the time, no dirt track racers used rear suspension, and the AMA did not allow brakes in dirt track competition until 1969. The bike is fitted with 19-inch alloy rims and Goodyear Eagle DT tires.
In order to compensate for the CL72's relatively wide cases and to also create cornering clearance for left-turn-only racing, Cates offset the motor about 21/2 inches to the right. Like many dirt track racers, he converted the motor to a right-side shift.
Cates introduced his frame at the 1962 Short Track Nationals, which were held at Santa Fe Speedway. That night, the bike was ridden by a well-known AMA pro named Darrel Dovel. It really stood out in the field of single-cylinder machines. Cycle World wrote, "...the scream of Darrel Dovel's Honda made a nice counter-tenor to the blat-blat of the little BSAs, Triumphs, and Harley Sprints." Dovel won his heat, and finished fourth in the final. The legendary Carroll Resweber took the championship that night.
Cates went on to sell about 100 frames for the CL72 motor. The frame on Kenny Thomas' bike has no serial number because it's the very first prototype; it's the only one fitted with a brass rub plate where the chain runs over the frame. Subsequent frames were modified for better chain clearance. Early photos of this frame show that it originally had an adjustable axle plate, allowing the racer to tune rear ride height and wheelbase for different tracks. At some point, that system was replaced by a more conventional welded-in tab. The only other significant modification to the frame was made in about 1965, when a novice rider crashed through a fence in Rockport, Indiana. The crash bent the steering head area, and the main frame member was reinforced with an inner loop of steel bar at the same time the repairs were made.
Cates sold his prototype racer to Paul Garrison, who was a Honda dealer in Evansville, Illinois. Garrison sponsored some Novice riders in 1963 and '64. By the mid-'60s however, advances among competing bikes had rendered the CL72 obsolete. Harley Davidson's Aermacch subsidiary built a short-rod racing version 250cc motor installed in Harley Sprints, and along with the hairy, two-stroke Bultaco Astro, the two came to dominate Class A racing. For the next few years, the little Honda was used as a play bike, putting in only the occasional appearance in an amateur race.
In 1968, Kenny Thomas, who was then a Honda dealer in Kentucky, bought the bike. He rebuilt it, and raced it the following winter in Nashville, on the concrete arena floor. As he recalls, "I used it that winter in a few amateur races, but after the AMA allowed brakes, it wasn't competitive. Then in the early '70s they made us put mufflers on the bikes, and that choked it right down." Thomas parked the bike in his shed, and forgot about it until New Year's Day 1996, when he brought it inside and began restoring it so he could go racing once again, with the American Historic Racing Motorcycle Association.
Ironically, despite the fact that the bikes (and the riders!) are getting older in AHRMA racing, they're faster than ever. Thomas spent two years figuring out how to make the CL72 motor competitive for the second time. He installed 12:1 Powroll pistons and lightened the crankshaft by 5.5 pounds. Converting the ignition from points to a Boyer-Brandsen electronic unit immediately allowed the bike to rev 2500 rpm higher (the current redline is 11,500 rpm.) Titanium valve-spring retainers help keep Manley stainless steel valves out of the way of the pistons at those speeds.
The result of this development? After watching Thomas' heat race on the Ashland half-mile, I think the bike might be more at home on a true short track. But his biggest challenge is that AHRMA's Classic 250 rules allow bikes made until 1967. Cates built the bike to compete with Triumph Cubs and BSA C15s in the early '60s; he didn't anticipate the short-rod Sprints and Bultacos that came later in the decade. Those bikes dominated Class A racing then, and they dominate AHRMA Classic 250 racing now.
Since rebuilding the bike and coming out of retirement to ride it, Kenny Thomas has won several heat races. "The bike will run with 'em. The problem is that I can't run with 'em," he volunteers, perhaps with undue modesty. In his day, Thomas was a fast guy--in fact, in 1968 he rode a Honda 160 to the AMA scrambles championship in the 175cc class--but he's 63 years old now. "I think my son could give these guys a run for their money," Thomas says, "He's a capable rider."
I met his son at the Ashland races, and he explained, "Dad says he'll let me race it--when he retires." A rueful smile made me think he'd heard this promise for years. Still, with any luck, one Thomas or another may well give this historic machine one more victory. In the meantime, the packed grandstand at the Ashland County Fairgrounds responded the same way the crowd did at Santa Fe Speedway when the bike was first raced in 1962. A reporter at that long-ago event noted that even though Darrel Dovel failed to reach the podium in the feature race, "...the scream of Dovel's Honda made everyone sit up and listen."