Jim rye

Daytona super111 will not tick over
my daytona sits on an optimate while not in use and it will start and tick over once disconnected however after a few miles it will only tick over with the lights off . If i turn them on the engine will run rough and cut out.
I have changed the 3 coils , the pick up coil , the battery and checked the voltage .
When its first started it reads about 14v and then it drops t0 about 13.5 but when you turn the lights on it drops below 12v
could the alternator be on the way out causing tick over problem because when you rev it up it runs fine until the revs drop to tick over.
Carbs have been cleaned and serviced by triumph but no change help!!!!!!

 

Many thanks for the advice steve i might just try changing the pick up coil again .
It does seem strange that as soon as i add electrical load the problems start its as if it begins to run out of spark at tick over !!!!
When the voltage drops below 12v under load do you think this could be the issue
once it cuts out it will start no problem the battery seems to turn it over as normal