Just purchased a Sony mex m100bt head unit which has the built in amp that delivers 40 rms per channel. I was looking to pair this with infinity kappa 62.11i but they are 2 ohm rated and the Sony is 4-8 ohms. Will the kappas still work? Thanks!

 

No they won't and you still need an amp. If you're only doing 2 speakers there's some fairly cheap amp options but there's the likelihood that you'll lose some or all of your FM.

 

Those HU's are good for cars. But they make no sense on a bike. As SB said you're gonna need an amp. With the Kappa's go with the Cervin Vega B52. You'll hear em at 80 with that amp.