To check timing is simple. Do you have a timing light? Hook it to a 12v pwr source, clamp the do-dad around the plug wire, open the inspection hole, start engine, shine gun in hole. Simple. When you shine in hole you are checking to see that the 'f' mark is lining up with groove in inspection hole. The 'f' mark also usually has a white dot w/ it. Now you have 'checked' timing. To adjust timing, remove CDI cover, now the outer ring is what controls timing. Loosen the two screws and rotate the plate either fwd or bkwd to get the 'f' mark to line up. This may sound involved, but when you see it you'll understand. Hope this helps.
Sam from Florida
1985 BIGRED $ 200X