I had taken the very slight and occasional tremors as part of the 103 running .
Replacing all the ignition consumables had no effect , but now engine is running perfectly smooth and steady .How?
The engine had a slight belt chirp when starting from cold, replacing the bad tensioner, belt and the bent adjuster rectified the noise.While the belt was out i serviced the alternator ,cleaned the commutator and replaced the voltage regulator as the bushes were down to a few mm.
The voltage now is 14.1V as compared to 13.6 V earlier on and dipping under 13V with the blower wiper and headlight load on.
I believe the charging system must be perfect too to achieve good running when all the other parameters are correct.
mak