[wayned]

I could swear it has no engine , just a group of gremlins out for a laugh.

On rechecking a plug was found to be duff (intermittent fault mebbie) but no spark was found at the horiz cylinder plug (a known good one).
I swapped leads over .. no result.
then I swapped ignition coils .. the horizontal cylinder fired .. AND SO DID THE VERTICAL???

Now after putting everything back in its place the problem has disappeared .. no sign of it during a 50 mile ride .

I say again .. its those goddamn gremlins .. I'm sure of it.

Thanks shazamm .. yes I didnt drain the tank completely so it may be gummed injectors .. How would I go about cleaning them ?