EFI is great when it's new, but I know of a number of EFI enduro/trail bikes that have had to be towed home. You get a bike that's a few years old, has been dumped in a creek, or washed thoroughly every ride, and you start to see connector issues. Plus any wiring rubbing as Nathan said. Not to mention TPS values seemingly changing of their own accord, without the input of owners trying to "tune" the bike to a stop with aftermarket controllers. These bikes really don't have a complex sensor system, but you still arent easily going to do much to one without the OEM Factory Diagnostics. And the old "put on the Computer to see what wrong with an EFI bike" is pretty much a crock, as all you often get is a warning of a high or low voltage problem which then has to be solved by good old mechanic's knowledge and skills anyway.