I'm picking the bike up tonight from the dealer. I'm going to pull the 10' off and put it on the 09' to make sure it fits. I would think the efi would take care if it was leaner/richer, but I know nothing about efi.
The bike would need some kind of 02 sensor for such things. I'm not sure about the EFI system on the Kaw but I suspect its basic EFI such as engine temp, air temp, manifold pressure, etc. The EFI system would need something to read how much oxygen is in the exhaust flow. I think this EFI stuff on bike dirt is all based on engine temp, air temp, engine speed, throttle position for base information for timing and fuel curve. But maybe somebody can provide better information. What about a head pipe guard?