>Anyway, this afternooon I ripped all the Amal gear off and fitted
>the origional Mikarb.

If you decide to put it back on later, I'd be watchful for possible
air leak(s) and set the idle
throttle opening 'way down. Start at 1/2 turn above full closed and
work your way up.
No way a properly-tickled Amal should under-perform a Mik - although,
of course, if the Mik's
properly set up, it should work just as well.