The Honda GB250 Clubman is more than a motorcycle; it is a rolling sculpture of 1980s Japanese engineering romanticizing British cool. But sculptures don't idle smoothly; they don't carry you through sweeping bends.
You might be tempted to use a generic manual for a Honda CB250 or a single-cylinder dirt bike. Do not do this. The GB250 is a mechanical anomaly. While it shares the basic bore and stroke with the CB250RS of the same era, the Clubman features unique components that require specific tolerances. Honda Gb250 Clubman Service Manual