[fizzwheel]

I just used a Normal Allen key, I used the long side of the Allen key and put that onto the bolt, that left the short bit of the allen key poking out of the bottom of the fork. I then used a long piece of hollow tube and stuck that on the end of the allen key a bit like you'd use a break bar and that gave enough leverage to crack the bolt and I was able to undo it just using the allen key.