The most difficult part here is knowing you conversion rate for the low traffic/CTR hours. For half of all my products 1a.m-6a.m my Ctr Is horrible. So ask, are the ad groups with low-CTR converting well in the low traffic/CTR time frame? Sometimes i shut off my adgroups within these hours just so I can see an exact CTR. To answer you orginal question, 6a.m.-9a.m is about the time most people start their campaigns. the US traffic picks up here, so people do start buying, but for some niches it may be more towards 8a.m. Your probably wasting a little time worrying about this, to run saturdays or not is a bigger question IMO. If it converts, usually run it 24 hours, if your on a budget or trying out a product, run 12 hours or less in prime hours. Vene