Spinning around the forum seeking solutions for wireless communication via Audio System 6.5 I found many information but my focus was a low cost (approx. $100.00) with no loss of functions I have with the cable.

As the result I got to a divided system.
One that transmits audio from System 6.5 to the helmet (or earphone)
and other system to transmit voice from the helmet to the System 6.5.

The diagram illustrates the solution


Material I used

1 x DIN 7 connector to connect in the rider or passenger plug
1 x P2 Connector female to the microphone receiver. Cable wires to DIN 7 pins 1 and 4
1 x P2 Connector male to the Bluetooth audio transmitter. Cable wires to DIN 7 pins 2,5 and 3
1 x audio Wireless Lavalier Microphone (transmitter and receiver)- it costs approx. $ 36,00
1 x Low Latency Bluetooth transmitter - it costs approx. $ 29,00
1 x Bluetooth earphone – it costs approx. $20,00
1 x 5 wire audio cable about 2 feet long
some skill to perform the welds (the hard work).

All you have to do is to build the cable connecting the Din 7 to the P2 connetors and plug the other components.
Pinout is:As far as I could test the system is 100% functional, as with cable, including CB radio, voice commands, intercom, navigation, media and phone. My longest use took about 5 hours without battery issues.
With a 2 ft long cable it is possible to place the transmitter and microphone receiver in the media Bay located in motorcycle dash. These two elements may be battery charged while riding using the 12 V outlet located nearby..

The Bluetooth earphone may be replaced by
a Bluetooth receiver it costs $ 15,00
a low cost earbud or two speakers mounted inside the helmet (similar to the original cable solution).


The components I used I bougth in Amazon:
Wireless Lavalier MicrophoneBluetooth transmitterThe picture shows the final cable with transmitter and mic
receiver.



As a new member in the forum I hope this will help someone.

 

Good solution. I am currently using SENA Freewire and SENA 20S with phone..