I'm not sure that my QFM dual cell mod has added crazy fast speed, shouldn't this thing be travelling 2x as fast as a normal stock bit? I've checked my surgical procedure and I know they are hooked in series. Is it possible that I cooked my stock batteries with a 3volt 600mA charger-having left it charging for no more than 5min? I did hear a faint 'ticking' from one of the batteries after charging, but didn't see any leakage or whatnot. How fast should a dual cell go with a 2.6 motor compared to a stock bit?