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.

Bit of flex pipe cut to length would sort it easily enough.
Not stock but functional and unseen when fitted.

Hi Gus,
Message me your email address and preferred format.

"set of four vac guages", which ones Graham? There are some real cheap absolute rubbish chinese guages available on various auction and dealer sites. The only way to tell if the ones that turn up are reliable is to test each of the four guages on the same cylinder in turn. Obviously they s...

It's sprung loaded and allows you to lift the bike off the side stand with the engine continuing to run. If you don't press and hold it as soon as you take the Wight off the side stand the ignition will cut out.

Hi. Maybe not relevant on an R but my parts catalog shows also shows the later ( simple reliable set up ) plunger type stand switch. My B2 has unused wires for it behind the sprocket cover. Cant see how it was originally mounted though without frame adaption. Have you got the diagram of the side st...