i don't understand how what the compression numbers mean 10:1, 11.5:1, what does it all mean??? can someone please help a newbie out?

 

It refers to the compression applied to the intake charge(fuel & air) entering the combustion chamber. Higher ratios mean more highly compressed and therefore greater energy release when ignited. It's a good way to gain HP since it's essentially increasing efficiency, something Hondas already have in abundance. Naturally if you increase compression you're making more power and therefore more heat, stressing components a bit more. It's a good deal though, and generally you can get to a bit over 12:1 before there's a significant risk of detonation(preliminary fuel ignition).