Hi Everyone,
Just to add to your discussion, other things which reduce the idle are the following:
1. Reduce air leak after the venturi (manifold and crankcase o'rings and crankcase oil seal)
2. Non functioning governor or vacuum control (connection between rear of carby and bottom of the engine)
3. Poppet valve setting (the highest step is the lowest idle or change with later model black poppet valve)
4. Adding cam brass spacers.
5. Changing the return spring with a softer one (less gram e.g. 150gm. The stiffer the higher the revs)
6. Changing the jet with lower flow rate in ml/min (mainly the two rings)
CM
