Flat track racing is all the rage in Europe and the States, but it hasn’t really caught on in South Africa yet. There’s no official race series there—just the occasional ‘run what ya brung’ shindig, where the emphasis is on fun rather than hard-nosed competition.
That hasn’t stopped Johannesburg local Justin Steyn from building his ideal flat track rig though—a replica of Honda’s late-80s RS600 race bike.
The RS600 was the baby brother to the dominant RS750, purpose-built for short tracks and TT circuits. It was never a production model, and there are very few examples out there, but it was basically a works HRC XR600R motor in a Knight Racing frame.
The idea was sparked when Justin entered the only annual event in his area—’Stofskop’ (translated from Afrikaans as ‘dust kick’). He started on his Honda CR250R, then closed out the day running laps on a mate’s BSA bobber.
“I was hooked and wanted to build something more suited to flat track racing,” he tells us. “I wanted to feel the slide—and the CR250 on MX tires wouldn’t allow it.”
“So I set out to find a donor. I thought I’d build something that would tick two boxes: a cheeky bread ‘n milk runner, as well as a flat track weapon for those odd occasions.”
Justin found a 1998 Honda XR600R at a Honda dealership, that had gone in for some work. It was clean and licensed, so he snatched it up and immediately put his credit card to work.
First on the list was a full body kit from Redmax Speed Shop in the UK. The kit included the tank, tail, seat, fork guards, front number plate, and a set of flat track bars. Next up was a pair of 19” Sun rims and new spokes, from Central Wheel Components.
Justin’s budget didn’t go as far as sourcing an original (or replica) Knight frame though, so the XR chassis would have to do. He roped in his good friend ‘Uncle Phil’ to tackle the fabrication side of things—the same gentleman who helped out on his stunning CB550 Dick Mann replica.
Phil de-tabbed the frame, and made up a new set of triple clamps to hold a pair of early-2000s Yamaha R6 Showa forks. Justin had a pair of Honda CR250 rear hubs lying around, so the guys shaved the sprocket mounts off one of them to use it up front, and laced up the wheels.
Rather than try to get the CR hub to play nice with the XR’s swing arm, Justin figured he’d install a CRF swing arm instead. But that was easier said than done; Phil ended up welding the XR arm’s pivot spindle to the CRF unit, and shortening it by 60 mm.
And since it was a custom arrangement already, he added new shock mounts to convert it to a dual shock setup, “in keeping with the 80s flava.” A pair of Bitubo shocks rounded out the package. (Justin at CycleWorx was responsible for the suspension work at both ends).
Since the motor was running strong, Justin focused the engine work around the intake. He slapped on a brand new 38 mm Keihin CR carb, along with a few carb upgrades from Tokyo Mods. Phil fabbed up a new exhaust too (there’s a Yoshimura sticker on it, for the sake of appearances).
Justin didn’t go completely overboard though. He cut costs by hanging onto parts like the OEM brakes, switchgear and controls. And he kept the front brake too, to keep a measure of day-to-day usability.
The first iteration of the build wrapped up the night before the last Stofskop event. After just a few hundred meters of shakedown, Justin was lined up to race.
“I heard the announcer giving some love to two South African moto legends, and thought ‘ah f**k, I’ve got to race these guys’. I grabbed a handful of throttle and lit up the rear tyre, but she started gaining traction and I realized I was up front—I had the holeshot!”
“The rest of the day went much the same, winning all but the last heat. I was stoked, the bike performed brilliantly, and having the right flat track setup is what got the wins.”
That was last year, and all the work since then has been focused on cosmetics and tweaks. The bike now wears its intended livery—a killer retro HRC scheme done by Wicked Wayne paints, along with fresh gloss on the frame and motor.
Richie at Racestar Graffix sorted Justin out with a bunch of custom decals, including some Knight Racing stickers to throw off pundits, and an OEM style warranty info decal for the tail. Then Alf at E.C.C. Customs reassembled everything, ran through a couple of mechanical niggles and “tuned her to run beautifully.”
Justin’s RS600 replica is picture-perfect, and is sure to cause jaws to drop when it lines up for the 2019 Stofskop this weekend. But it’s not going to stay shiny for long..
Published at Thu, 05 Sep 2019 17:01:25 +0000