Here is a link to a source that seams to shed some light on the ACV function - www.thumperfaq.com/acv.htm Hasse Even better is this link to the Keihin CVK mysteries where 'ACV' is named 'Coasting Enricher' - www.gadgetjq.com/keihin_carb.htm
Second edit: This issue with the 'ACV' is also discussed in the BA thread 'I really need help on this one!! Carb issue?'!