Some rough running that wasn't coils

Had to go out on the Trophy Tuesday evening and the destination
involved about 45 minutes of city traffic getting there and
back. It was running warm, but the fan coped OK. Then just
before getting back into open countryside for the home run, it
started acting up. Not as smooth as usually and I could here
misfiring. Tank was about 2/3rds down, so I wondered if it was a
fuelling problem and switched to reserve, which helped with an
earlier problem where there was vacuum loss due to a pinched
hose. It helped some, but not a lot. I got home and it was still
rough and wouldn't hold idle.

Probably a coil gone, I thought, so ordered a new one from Jack
Lilley's. Took her apart this afternoon and removed the left
side coil to replace with a new one. Started the engine to see
if it improved the running and noticed it was draughty where I
was holding the coil. Problem solved: Not a coil at all, but a
missing vacuum cap off the vent on number one carb. Now, how on
earth do they come off? They are tight plastic caps held on by a
wire clip. I've borrowed one off my 95 Speed Triple, same Mikuni
carbs. I changed all the plugs because it was about due for a
service anyway and put it all back together. Runs fine.

Still love to know how a vacuum cap and wire can just vanish
like that!

Any now I have a new coil I don't need (well, not right now and
03 1200s don't seem to have too many coil problems) so if anyone
in the UK needs a new 1200 dual output coil, for £50 (save £25)
let me know and it'll go in the post.

Regards

Alec