When we first got the call about a potential Bridgestone restoration job, John in particular was eager to see it come in. While it was the first Bridgestone a customer had ever asked us to fully restore, it was by no means his first experience with the brand. As many of you may recall, John’s very first motorcycle was a 1967 Bridgestone 175CC. The opportunity to revisit the bike that helped first fuel his passion for motorcycles was one that brought with it a flood of fond memories.
Several weeks later, when the best opportunity to take a day trip away from his own seasonal business, Mary’s Greenhouse of Elkins, WV presented itself, new customer Larry Gouer arrived at the back of our shop with a 1967 Racer 175CC in tow. It had certainly seen better days, but as we listened to Larry’s tales of its storied history- including several 1st place trophies and one particularly exhilarating jump where the front wheel fell off in midair- we couldn’t help but find ourselves forming a special affinity toward this particular project.
Unsurprisingly, John spent nearly every moment of his free time that following weekend cleaning the carburetors and points to get it running. Hearing it fire for the first time is always a high point in these types of projects, signaling the green light that it makes sense to move forward with the project and let our more involved work begin.
Began it did and involved it were. We started by completely stripping the bike down to the bare frame. We dropped the frame and other miscellaneous parts off to Jason at Performance Powdercoating off of James Rd. in Columbus. Jason has been our go-to powder coater for many years as he delivers quality work and reliable turn around times. We then tore the motor down to the crankshaft so we could freshen up the rings and seals.
After coming up with a detailed list of what was needed, Rachel began the tedious task of trying to source parts. This topped the charts in term of difficulty, as we can only think of one other project (a small CC Kawasaki) that proved equally as challenging. Through a combination of NOS and remanufactured parts we were able to secure most of the parts we needed.
With everything back from the powder coater, we began reassembling the frame by installing the swingarm, triple clamp, handlebars, and forks. The rims arrived back from Custom Chrome Plating in Grafton, OH and although this was the first time we’ve used them, it won’t be the last. They did an excellent job and left us thoroughly impressed. To keep with the aesthetics of the period, we went with retro-inspired Duro tires.
Once we had the rolling chassis ready to go, we refocused our efforts on the two-stroke “rotary valve” twin engine. Instead of the traditional placement of carburetors on the back of the engine, a rotary valve two-stroke has dual carburetors hung off the sides of the bike. This allows it to draw air much closer to the crankshaft and uses a plate to draw fresh air and fuel into the cylinder to create combustion. We set the ignition timing by using a dial indicator inserted through the spark plug hole on either cylinder. We set the piston at TDC (top dead center) and moved the points to open when it was appropriate.
Throughout this project there were some obvious differences that set the racing model we were working with apart from the standard 175CC line. A definitive way to differentiate a standard 175CC from a 175CC Racer is to look at the number stamped on the cylinder. The standard will have “179CC” stamped whereas the Racer will be stamped with “175CC” so that it can compete in that class. Although the standard bikes could otherwise be converted into a racing model, this indicator verifies which bikes were factory-destined to be converted to a Racer and which were not. Our understanding of the factory Racer conversion process is this: Bridgestone sent 175CC models to select dealers with an instruction pamphlet on how to modify it into a Racer. This would include things such as extending the rear swingarm and bending the rear frame section to accommodate this extension. The Racers did not have a generator driving the points and charging the battery. It did not have a charging system at all. The generator was completely gutted at these select dealers and the bike would only run as long as the battery was charged.
With the motor timed, we began cleaning and polishing everything we could and found that many parts were able to be restored with enough elbow grease effort versus having to be replaced. We had the springs on the factory-custom off-road shocks powder coated instead of replacing as we typically would because the front of the bike was custom from the factory as well with a different triple tree and front forks fitted for off-road use.
We sent the seat out to be recovered and then began addressing the tank. The tank itself proved to be quite the daunting task, and we knew it was key in achieving a professional-level restoration. The inside was quite rough but worthy of salvage, and we were able to clean and coat it in-house. The biggest obstacle with the tank was the finish. We first had to have it chromed, then powder coated to create a surface that could be adhered to since paint cannot stick to chrome, then painted. To say the least, it was a tall order to find someone capable of reproducing the original look, and required three separate specialists to achieve the desired finish. It was an extremely long process, but in the end, worth it.
inted fenders, and the exhaust pipes that were also factory-custom for the bike. On principle, we replaced all rubber components available such as the foot pegs, grips, fork boots, and air intake boots. We made a custom kill switch because the original was broken and unavailable elsewhere. We also replaced the Bridgestone badge on the tank. Many of these parts were incredibly difficult to source because they are such an obscure brand.
Finally, it was time to start the bike. John was very anxious to hear it run, especially with the factory-custom exhaust. We mixed some two-stroke fuel, ran fuel lines to the carburetors, and gave it a kick! The bike was particularly hard to start due to having no choke circuits on the Racer model. Once started, though, it ran extremely well. The sound was unreal and it is definitely one of the better sounding two-strokes out there.
It surprised us with its speed, and the front wheel seemed to find its way into the air whenever you cracked the throttle. We noted that its shifting sequence was unusual as well, with neutral all the way at the top and 5 down.
We took it to our booth at the Euro Bike Night Show this past summer and it was definitely a popular conversation starter! This was the first year we were able to attend this newer show and we’re excited to watch it continue to grow. For 2022 they’re looking to shift the event to a late September date when travel plans typically die down and Ohio puts out some of its best riding weather. To keep up with the most recent information on the event, or to connect with fellow like-minded vintage riders, check out and join the Columbus Area Vintage Motorcycle Group on Facebook!
Larry recently hauled the Racer back to its home in West Virginia and dropped off two smaller Bridgestone’s for us to begin work on in its place. Stay tuned for updates!
