motorcycle intercom

i am looking for kind people here to help me with my idea of building a simple intercom circuit between motorcycle rider and a back ride. i am a motorcycle enthusiast and i would like to talk with my back rider most of the time during the trip. this will be useful instead of taking out our helmet.

thank you guys and more power...

Buy one, they cost very little, certainly far less than you could build one for!.

Agree with Nigel. I've seen many of these on Ebay for $25, not worth building.

thanks guys! appreciate your replies...