This kit was 100% bolt on and very easy to install. Torque is insane I feel like this is the power a grom should have out of the box it completely changes the bike. I am very impressed with the tune on the ecu. I'm on the fence as far as going to the aracer but it runs and idles so good the only benefit would be if I were to switch to different fuels as I don't really plan on going much further with the grom. Time will tell but if you are thinking about installing a BBK just do it!