Whats good everyone, new to the forum, picked up a yfz450r a few weeks ago and broke it in this 4th of july weekend, had a blast. I was just wondering, if the EFI Controller exower Commander* etc is really neccessary...?Lookin to put in a K/N filter w/outerwear, lid off.. i already have the FMF Factory 4.1 slip-on installed (stock filter-lid on), but being fuel injected, do I really need to pony up the cash for and EFI controller? wouldn't just takin off the lid and putting in the KN filter be enough?... and/or will it damage my yfz450r if I don't get the EFI controller...? any advice, pointers, help will be appreciated...thanks,..