About 10 years ago, I sat down to transcribe my history with the Honda motorcycle brand, beginning in 1967 with my first motorcycle, a CL90 Honda Scrambler. Walking through a period of some 50 years of riding, buying/selling and experiencing a wide range of vintage Honda motorcycles, I wound up with some 60 pages of my personal involvement with the Honda brand. This story is an excerpt from the bigger “In search of a Honda” story, a Hondabiography, if you will.
From the beginning, it took me 7 years to enter the realm of sports racing and it ended with a good result in the end of my year of efforts. Starting with an unlikely base in a 4-stroke Honda CB125S1 125cc street bike, I was able to modify it to a point where it was competitive with a good many other branded 125cc models which were available during the early 1970s. I really only entered the fray to see if I could make the bike fast enough to keep up with the current crop of similar street machines and learn something about riding competitively, although on the bottom rungs of the racing scene. I didn’t go into it with hopes, dreams and the drive to become a winning rider, it all just sort of happened on its own.
My little piece of motorcycle racing history culminated in winning the 125cc Production Class Championship running in two different racing organizations that year, the AFM and CMC. I began my road-racing hobby in 1973 on a $300 CB100, with one win at Willow Springs, when only two bikes were entered and I was the winner at my first racing experience.
AHMC factory photo CB125S1
1974
With amazing synchronicity, Honda released an upgraded version of their formerly drum-braked CB125S in 1974, installing a trick cable-operated disc brake on the front wheel. I felt that this combination would be just the answer to fulfill my road-racing dreams. Then, I discovered that Yoshimura Racing was selling Road Race pistons, lightweight crankshafts and camshafts for these bikes! I started with the slipper skirt racing piston and camshaft, along with some racing valve springs. When I installed the camshaft in the head and turned it on its bearings, I discovered that the valves would hit each other on the way back to overlap. Pops Yoshimura had his own unique ideas about camshaft ramp opening and closing profiles, which were extreme to say the least. I didn‟t know why they designed this cam the way it was, but I decided to grind down the edges of the valves, until they had some clearance when they opened. After that, I had to slot the cam sprocket and degree in the camshaft, so the valves wouldn‟t hit the piston. Eventually, it all came together and I fired it up and ran down the street, with the tachometer barely able to keep up with the newly revitalized engine. I tried to break in the piston and rings as much as I could without running the motor up to red-line in each gear, but it was quite difficult. I changed the jetting a bit, still using the stock carburetor and found it really “perky,” as well as “peaky” for a little four-stroke single. These bikes peaked at about 65 mph in stock condition, but it was now pulling past 75 mph and might have even more in it, once it got on the track. I felt that I was ready to take on that swarm of 125cc two-stroke (mostly) Production bikes, as the season opener at Riverside Raceway loomed near. Everything was brand new to me, including the track.
To go racing, you have to have the correct safety gear from head to foot. I didn’t know where to go find a road racing set of leathers, but I knew a guy…
The Floyd Emde family lived in National City and Floyd had his motorcycle shop on National Ave. Floyd and his son Don, were the only father-son winners of the Daytona 200 race in history. I guess that I asked Don about where to find some used racing leathers and he said, "Oh, I have some spare leathers from when I was racing with BSA." We happened to be the same general size and for something like $50 I had a set of real racing leathers. My USAF boots and gloves were sturdy enough for the task and I purchased a Bell Star helmet to finish off the gear list. It was time to go racing!
I rechecked the “fixed” ignition timing (Yoshimura racing points cam) and headed out for some practice laps to determine if the jetting and gearing were going to be correct for the track that day. Riverside Raceway was WAY different than riding in the mountains or even at Willow Springs. Turn 9 was a banked sweeper where you could just keep it wide open and lean over as far as you could. At the other end of the track, Turns 6 and 7-7A were a series of snaky S-bends, up and down hills requiring off camber braking in a corner. It was kind of disconcerting at first, but with only 125ccs underneath, it wasn’t likely to buck me off from massive applications of power in the turns. I did plug checks to check the main jet sizes and rechecked everything a few more times in the second practice session. The bike was pulling towards 80 mph, but vibrated like CRAZY at red-line (11,000+ rpm), numbing my hands in just a few laps.
I entered both the 125cc GP and the 125cc Production classes, in order to get some track time and dial in the bike. The GP race was, of course, a flop for me, as the winners were going about 90-100 mph. Back in the pits, a fellow racer came by to tell me that my lap times were good enough to have placed me well into the Top 5, based on last year‟s race times for the Production class. That was pretty terrific news to start the day! I nervously eyed the competition in the Production race, noting a gathering of older Yamaha 2-stroke twins, a Kawasaki 90, and other street-based machinery. I think that there were about 8-12 entries in the class and I was the only Honda four-stroke machine to be seen. They waved the flag and off I went, slipping the clutch at 10,000 rpm and paddling along with my feet to get some forward motion built up before the first corner.
First
lap, first corner racing is pretty intense, as everyone is vying for
the lead simultaneously. The little Honda pulled out towards the
front and everyone found their own pathway through Turn 1 and
concentrated towards the next section of the track. As I accelerated
through the turn exits and used the great disc brake to setup my
corners, I found a good rhythm after a lap or so, in the thick of
traffic and began to pull towards the front-runners. I tucked into
the “draft” of all the bikes ahead, wherever I could and finally
pulled out in front, by a slim margin. Of course, my competitors were
using my speed to keep me close, as well, looking for an opening to
pass or slingshot by me on the straights. I kept my head down and
watched my lines through the corners carefully, lap after lap. I was
relieved to see the White Flag, signifying that we were on the final
circuit and when the Start-Finish line appeared again, I was alone in
front! New bike, new track, new everything and I won my first 125cc
Production road-race! Pretty thrilling stuff for me and even my
fellow racers were surprised at the speed of the CB125. I was a happy
guy, but my hands were again numbed by the engine vibration, so I
decided to invest in a racing crankshaft for the little “Racer that
could.”
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