Like anything I do with regard to technology, the simple idea of adding a Sat Nav to my scooter has got a little bit out of hand.

A couple of weeks ago on this blog I demonstrated the case I bought to attach my existing Car Sat Nav (a Navigo flashed as a TomTom) to my scooter. I noticed at the time that the tiny Navigo looked a little bit lost in the large case, so I started shopping around for a new Widescreen Sat Nav. I also decided that my new device should have the ability to somehow wirelessly transmit it’s voice instructions to a receiver in my helmet and as usual I wanted to spend as little money as possible.

In the end I settled on a TomTom 520.

Other than my familiarity with the TomTom OS  the main reason for choosing this model was that it was the cheapest device I could find that could transmit its sound output over FM to a radio receiver. My intention with this was to keep a small FM radio in my jacket pocket and wear in-the-ear headphones inside my helmet.  So I tried this out, and it was working fine – albeit with some interference – until I did a firmware update on the TomTom – at which point it then stopped working.

Apparently TomTom had to remove the ‘transmit voice instructions to FM’ feature because it’s illegal in a number of European countries. By some strange quirk – it is still legal to transmit the voice as long as the TomTom is playing music at the same time!? The work-around then is a simple matter of playing a looped silent MP3 continuously in the background.

However – and perhaps as a concession to disgruntled owners, the new firmware also added the ability to transmit the voice to a ‘Bluetooth HiFi Device’ – presumably a car stereo. So I set about finding a suitable receiver for this function.

I came up with the Sony Ericsson MBR-100 The MBR-100 is a tiny rechargeable A2DP receiver/transmitter. It has one button (on/off/connect) and a 3.5mm phono socket. Paired with a suitable device it can either transmit or receive sound via bluetooth.It works perfectly with the TomTom – it picks up the sound and relays it to the headphones without any interference.

So now I have bought a £40 Case, a £130 TomTom and a £30 Bluetooth Receiver. For £200 I have assembled my complete bike Sat Nav solution. I imagine that the only advantage a purpose made Bike Sat Nav would now have would be an easier to read screen. My TomTom 520 display really does wash out badly in normal daylight and this is something to bear in mind when deciding whether to pay the extra £150+ to get a purpose made motorbike sat nav.