Promising replies so far.
Weird thing is my previous Eagle F1 assy developed the same bulge during the winter, but I put that down to the potholes in the road at the time. However speaking to wayne he says he has had the same bulge in 3 eagle f1s himself, but never in any of his other makes of tyre!
The sidewalls do seem soft to me, but I am coming from the R1Rs. They are good tyres but maybe a bit too fragile really.
Will contact the supplier and goodyear tonight and see what they say!