Graham, take two reading per cylinder. One cold, throttle fully open, no plugs, cranks the starter until reading stops increasing. Second same as first but with a few ml of oil squirted into the cylinder. A significant increase will show a rings/bore issue. No significant increase but low reading sh...

for instantaneous fuse popping your looking for a live feed shorting to ground, however mebe its me but im unsure what the 10a fuse is doin :oops: i.e is it protecting the feed from the relay contacts to the coils or protecting the relay coil from the battery feed either way you have a short to gro...

Well as every fuse you've put in has blown immediately the feed to the coils wouldn't be live so they should be fine.
Did it blow the fuse without turning on the ignition or did it blow as soon as you did?

How can they have gone heavy? unless they have been punctured?
Would a bit of heat to dry them out and dip in por15 not sort them out?
Correct part number 16031-024? Z fever Germany.

Sounds like the relay shorted directly to earth which blew the fuse. That probably means the connectors inside the relay will likely have fused in the closed position. If that's the case once the fuse was replaced, if it didn't blow again immediately, the battery might have already fried. Take a spa...

Have you got a colour tune David? That'll confirm mixture burn colour are all equal. Timing to both coils the same? Plugs all the same heat range? but that shouldn't affect header temps. Only other thing that could be affecting temp readings of the headers is whether they are twin walled or not but ...

Graham is the same vac cap that's blowing off or does it vary? For a vac cap to blow off you have positive pressure in the inlet when you should only have zero or negative pressure. If it's the same cap every time then that cylinder must either have a hanging valve or a poor seated valve or pre igni...

So it is running on 1 & 4 at tickover?

When starting on choke the mixture is highly rich so some smoke is likely. Black smoke is oil burn. Blue/grey smoke is rich mixture.
White smoke is condensation from water vapour burning off.
What colour are you getting Graham and when?

Bit of carb cleaner in the airbox will rule in or out any ignition issues and narrow it down to carbs

Dyna pick up? 1 & 4 pilots blocked? You can rule out the Dyna by timing 180 deg out (swopping feed wires) and swopping plug caps and see if the issue moves or not.

Graham, we spoke about the needle dampers when you called me yesterday

It looks to me like you've counted the first pin as the the one the mark is pointing to. It should be the one above the mark. This would rotate the inlet cam anticlockwise by one tooth which would make the sprocket bolts on the inlet cam a mirror image of the exhaust cam as they should be. And as pr...

sean_rfi wrote:I'm not sure if its some form of optical illusion but, as Zed9 says the lower inlet cam shell appears distorted or not supported (can be seen in the first/top photo).
It almost looks as tough some of the casting is missing?

??? Gasket obscuring the cap foot?

Can't see the position of the exhaust cam mark as its hidden behind the cam cap on your picture.