Two-Stroke Street Weapon from the Aloha State…
One of our favorite things is stumbling across a photograph of an amazing build, then playing detective in an attempt to track down the builder. That is exactly what happened with this RD350 street tracker. We ran across a low-quality, uncredited image of the bike on Instagram, then proceeded to go down the rabbit hole of cyberspace, searching forums and list serves, before finally arriving at the builder: Scott Zupner of Hawaii.
Scott has been racing since the early 70s at Indian Dunes in Southern California. In 1996, he moved to Hawaii, where he’s been a sponsored professional surfer and motocross rider, and got hooked started racing Supermoto in 2010. As he says:
“Motorcycle racing is not just a hobby for me — it’s a passion and a way of life.”
Scott has long been a fan of vintage air-cooled two-strokes, as well as the flat track racers of the 60s and 70s. We can’t think of better tribute to those loves than this RD350 special, built in his personal shop. This is simply our favorite two-stroke tracker ever — an absolute ripper.
Below, we get the full story directly from Scott Zupner himself.
Two-Stroke Street Tracker: In the Builder’s Words
I have been racing motorcycles since the early seventies at Indian Dunes in southern California. I raced every weekend and also raced in the World mini gran prix several times. I also raced at Saddleback park. I continued to race and free ride motocross for my whole life I have also been a sponsored professional surfer as well.
I got back into racing MX in 1995 in San Diego and then moved to Hawaii in 1996 where I also surfed and raced MX. I had been racing 250 amateur class and did very well bringing home plenty of trophies. In 2001 I finished in the top 10 for the state of Hawaii expert class racing. I took some time off to achieve some personal goals in my surfing career and I accomplished that with many sponsors, contests and photo publications.
In 2010 I started racing Supermoto and was instantly hooked. I have not missed one single race in almost four years and continue to excel at the sport. Its for sure the most fun I’ve ever had on two wheels. Motorcycle racing is not just a hobby for me — it’s a passion and a way of life. I simply can’t wait till my next event.
Besides racing, I have been restoring and building motorcycles most of my life. I really like vintage air cooled two strokes. I build out of my personal shop in Hawaii.
The RD350 street tracker has a custom nickel plated frame, rebuilt motor, Yamaha AT-1 tank.
Shouldered rims, Dunlop tires. I was inspired to build the bike because I really love vintage flat track motorcycles similar to this style raced in the sixties and seventies.
I would classify this bike as a street tracker. It also has a MZB ignition, no battery but does have a lighting coil and is street legal. Also Jemco supplied the exhaust parts but were fitting to the bike in the shop.
-Aloha Scott Zupner
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