Finished drawing of the sleeve drive by the talented Mr. Bob. As it turns out having the sleeve drive shaft rotating in the same direction as the main crankshaft really helped us. I’m sure that Sir Roy Fedden didn’t imagine we’d be doing this to his state of the art Aero engine some 70 odd years later! But even so, he no doubt faced the same design hurdles (and some more!).

Chain drive will be easy to achieve and adjust. The oil feed will be modified however as it is much easier to oil the sleeve ball joint by taking a drilling down the centre of the shaft. This means we won’t be able to run a points cam on the outside, so an alternative ignition system will need to be found. I think a hall sensor located close to the sleeve drive sprocket is probably the best solution, but I need to do some research.

Great progress though, I just need to get my hands on some parts first. Fingers crossed!