David’s Suzuki RG500 GP replica

David has brought three pretty unusual bikes to the RR workshop, but this one is really exceptional.

The engine and exhausts are built by Mark Dent, who is the bloke you go to when you want to rebuild one of these things. You could mistake the chassis for a 1990s Bimota or later Spondon. In fact it was designed and built by Mark Walker, who also assembled the whole bike and fabricated most of the detail parts. Which includes the yokes, swing arm, footrests, clutch cover, handlebars, battery box, fairing brackets, sub frame and R6 forks.

David bought the bike from Mark as a mostly-finished runner, but he didn’t like the basic loom and anyway wanted to add a different dash. David also did the paint scheme, and as he owns a business that can do fabrications, he’ll attend to the final details: making the kickstart fold away nicely, fit the speedo pickup, and change the battery from a lithium to a normal one.

It’s just a daytime MOT spec, but the loom was quite tricky to design and build. Two stroke fours get very hot so above all you have to keep the wires and sleeves away from the noisy thing in the middle. I also got a bit baffled by the Ignitech CDI ignition, which has two coil outputs. Ignitech’s online RG500 instructions say you should use both, but Mark Dent had only used one. I asked Jiri at Ignitech, who said running all four cylinders on one output is correct.

Ignitechs can often run two stroke power valves, but not Suzuki’s RG500 AEC, so that’s why there’s a Zeeltronic power valve driver in there too.

It’s great fun working on crazy one-off stuff. We fired it up outside the RR workshop. I thought it sounded super crisp, but David, who is a two stroke fanatic, reckoned it needed a bit of adjustment and a thrash to get to tip top condition. He sent the pics of the bodywork once he got the bike home.