OK, testing a bit limited at the moment due to being at work. This is what I have managed.
1.With cap off a good few revs doesn't produce any smoke.
2.Rocker to carb pipe is clear, can blow through that. Air filter OK as pipe feeds into side of carb. It is a bit oily though.
3. Tested suck/blow with filler cap a bit better with a sheet of paper in case my club hands couldn't feel properly.
4. Sheet of paper completely over cap hole stays in place so there must be suck. If I move it to leave a slight gap you can feel a slight blow up to 2/3 inches away, sheet starts to jump about and idle drops.
5. With cap on and finger blocking open end of pipe on cam follower cover then revs drop. Same effect as taking off filler cap but to a lesser extent i.e. revs don't drop so much.
Doesn't sound as bad as first thought then but just not sure of the change from suck to blow when the rocker cap 'seal' is broken. Any thoughts? Hopefully better than the ones when I walked back into the office looking like I had black lipstick on.
