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Valve clearance for Mk3 850 Commando...

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Can anyone help me!

...I'm planning to fit Boyer electronic ignition and I want to know if the valve clearances remain standard, ie: inlet at .006 and exhaust at .008.

I seem to remember that Mick Hemmings said set them both to about .0011.

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Tappet clearance would be affected by cam profile but not by ignition system. If you have a standard cam, set them to a nice tight .006" and .008" - watch out for indented valve stems.

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Previously wrote:

Tappet clearance would be affected by cam profile but not by ignition system. If you have a standard cam, set them to a nice tight .006" and .008" - watch out for indented valve stems.

Thanks for that. Think though that it has a PW 2 cam fitted. So I assume the clearances would have to increase?

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Thanks for that. Think though that it has a PW 2 cam fitted. So I assume the clearances would have to increase?

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Do you mean the PW3 ? It does indeed run the sort of clearances that would make a real bag of nails sound with a standard cam.

Have you bought the Boyer yet ? It might be worth talking to Mick again to see what he recommends. The old analogue Boyer has a less than ideal advance curve. There might be something more suitable now.

Mistral Engineering used to alter the advance on the RITA units when a PW3 was to be fitted.

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Have my facts wrong and mean an S2. Gen so far indicates .0010 for both inlet and outlet. Boyer system that I have is the Micro Mk3.

 


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