Hi Wayne,

All the engines are technically interchangeable, but you will need to make modifications depending on what motor is used. Things like flywheels and stators need to be changed, keeping the original MC16 items (mind you, an MC18 flywheel may give a useful ignition advance upgrade - but don't quote me on it!), and the G.P.S. socket will need blanking if you use an MC21 motor.

Other things though, like MC18/21 carbs make for a great upgrade to the MC16. You will need the later model insulators (MC21 with HRC stuffers are best) and to rejet, but they are naturally SO much better than the 28mm MC16 carbs.

I think Nigel Moss has an MC16 bottom end kicking around, and you could get your barrels repaired by Langcourts - go direct and it's around £100 a pot.

What is actually dead on your motor?

Andy.
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