Ok folks, So i bought the low profile USB charger by Belkin from Argos.

When i plug my iphone4s into it & turn the engine over i keep getting a message pop up on screen saying
"Charging is not supported by this Accessory"

This annoying screen message will flash up every 2 seconds or so

And judging from some of the comments ive seen googling, it appears to be an iphone4s problem and not the bikes charger. It would appear that the iphone4s has bigger power requirments, unlike previous iphones.

Does anyone know if this is true?

Is there a work around, other charging device that works with the 4S?

Yep, its a apple problem. Use the apple lead with a 12V adaptor that has a USB port. Thats what I do in the car.

There was a software change years ago but I thought only really old stuff wouldn't work with recent Apple stuff.

I use a small 12v to USB adapter and plug an Apple lead into it and that works. It is just such a pain that the door makes it hard to find a small enough plug

Na, its cause apple don't like 3rd party products.

I've tried 3 different cables, including the official iphone cable

You got a kinky to the Argos charger u are using.

Damned apple auto correct. I'll leave the error as its funny.

LOL http://www.argos.co.uk/static/Product/p ... IPHONE.htm

Yes something like that should work. I have a similar one in my car with my iPhone.

Tyred 2 or 3 i-phones in the car with the i-phone and a aftermarket charger non of the worked,
every other phone I have tyred charges ok so just put it down to i-phones being fussy, not
tied one on the Burger but it does not surprise me they don't charge or play up.