Ignition Timing

I was wondering if any of you guys could tell me how to turn the ignition timing to 28* from 33* with a Boyer electronic ignition switch already installed. I seem to have developed some 'flat' spots when cranking the throttle and every thing else seems ok. I've read the manuals but they don't explain how to 'turn' the timing backwards or forwards unless you have points installed.

Sorry, the bike in question is a 1972 Norton Commando. Thanks.

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Ignition

If the plastic circuit board that sits behind the points cover is warped will it have an effect upon the timing? That seems to be the only visible problem I might be having as far as the Boyer is concerned.

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