Hello Mark, Thanks for your suggestions, The "clutch" is just an idler wheel which is used to push on the drive belt and hence make it bear on the drive wheelto the rear wheel drive. As far as I can fathom this idler wheel should be either fully in or out. Surely it is bad engineering practice to allow the drive belt to partially slip to achieve different speeds?
The real problem is that the engine is over reving. I am afraid I don't know which block it is looks about 100cc by eye, but could be 160cc! There is a solid metal casting that mounts the carb to the block, not a hose. As far as balancing out vacuum against spring pressure via the diaphragm is concerned. I am stumped. The diaphragm doesn't seem to be connected to anything so I don't know how the diaphragm position controls the engine speed. Would you like to explain that one in a bit ore detail mark? Not being a smart a*$e here! I genuinely can't understand that one!
Thanks for trying to help,
Andrew.
