ringding

I've a C25 (same as a B25 to all intents and purposes) as a road bike. I run on 20W50 classic motor oil for the engine and primary cases. Gearbox is a 80W90. I wouldn't have thought the gearbox oil would change in a competition bike, but depending on whether you're running an oil filter or not you may be best running on a modern engine oil. What set up do you have?