I did a cursory search to see if this had been addressed and didn't come up with anything (remember, cursory search), so I thought I'd post this. My bike is an '08 Vision.
I use my iPhone for listening to my tunes. If I wasn't such a cheapskate and upgraded my data plan I could use it for Pandora also.
I started out with sticking my iPhone into the glove box and connecting it with the 3.5mm aux cable. That led me to wanting to be able to control the tunes from controls on the bike, so
I got the iPod cable at my local dealer, Thunder Alley, in Kennewick, WA, and plugged it in. Worked great, except I got the message "does not support charging." So I run my phone down while it's connected and playing tunes.
Then I got tired of stuffing the iPhone into the tiny space, plugged into the cable. Got to thinking a bluetooth solution would be good. Problem is, on the older Visions, the cable doesn't support charging, which means they also won't run an A2DP Bluetooth receiver. I won't get into the whys and wherefors, but it's my understanding that the connections in the 30 pin cable got switched around at some point. The older cables (such as for an '08 Vision) have the pin for charging in a location where it doesn't connect with the iPhone or iPod.
I hopped onto Amazon and found this:
Scosche passPORT Charging Adapter for iPod and iPhone (Black) This corrects the pin location so your iPod cable will provide a charge to the device (or power a Bluetooth Receiver). Next I ordered this Bluetooth receiver: Patuxoun Bluetooth A2DP Music Audio Receiver Adapter for Bose Sounddock and 30-Pin iPod iPhone Dock Speaker Total cost for both, under $35 shipped (I'm an Amazon junkie and use Prime for shipping).
I tested the Bluetooth adapter on my iHome alarm clock and it paired correctly with the iPhone right away and streamed music. Tonight I tested the setup on the bike. Seems to work just fine, though I haven't tested it with my helmet speakers or done anything other than hook the setup up in the garage. It seems that for the Bluetooth to pair properly, the bike has to be switched on and the radio on, selected to Aux. If you have everything plugged in before switching on the ignition, it may not pair properly. Setup is: 1) Plug the bike's male iPod cable into the female side of the passPORT adapter. 2) Plug the Patuoxun Adapter into the passPORT. The blue light on the adapter should light up showing it's got power. 3) If you haven't paired the adapter already with your phone or iPod or other Bluetooth device, do it now (Code is 0000). 4) Play music. Now I can keep my phone in my pocket on the bike instead of jamming it into that tiny little glove box, or whatever you want to call it.
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DIY Bluetooth - iPod or iPhone to Bike