Braking from 50-70mph braking hard the steering wheels shakes pretty violently - could it be due to the new pads fitted 300 miles or so ago? Don't think it was this bad before.

Have you checked all the wheel nuts are done up tight?

Warped disks, although you should fell this at all speeds, although will be worse at higher speeds...

Warped disks, although you should fell this at all speeds, although will be worse at higher speeds...

+1

If the discs are warped (or there is crap built up on them) then I would expect them to judder when you brake lightly but that should go when you brake hard.

Warped discs can judder under light and heavy braking. Have your discs changed

Pete :yes:

could be a fair few things tbh...from basic things like loose bolts to discs...to wheel balancing...to bushes mine did it due to knackered bushes

What about the discs being slightly dislodged when the pads were changed and a bit of rust or other debris lodging behind them resulting it them not being tightened on dead straight?

Pads Changed 300 miles ago, And now its vibrating. Definately sounds like warped discs.

As a mechanic, I would have to say get them discs changed.

... but if the problem wasn't there just before the pads were changed why should the problem now suddenly and coincidently arise if it's warped discs? No point in changing them if they're just not quite bedded properly. Discs not bedding properly is a common problem with MX-5s - admittedly don't know about Fabias...

Sorry, but you HAVE NOT warped the discs:

http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml

+1 from me on not bedding the pads in correctly...

The problems seems to have stopped or at least calmed down - probably the pads