Rumble on the Motorway...?

Hi All, I have had my 17" Kei Force 10 Alloys (205/40/17R) for about 3 weeks on my 1.2, 16v 53 plate clio mk2 now and I have just stepped onto the motorway, all is good until I'am in 5th gear and doing around 4000RPM and doing 80 mph I feel a rumble like judder on the steering wheel and on my feet through the pedals. Sure you will moan that I'am doin 80 in a 70 mph zone but I like to go fast... I hit 95mph and the rumble started to fade alittle until slowing down to turn off at a junction.

Can anyone help with my problem? do I need my arches widened by any chance? my tyres are professionally calibrated and fitted btw.



Regards, Adee