Some you win, some you lose...
Me and Nattboy removed his from his track bike, we spent ages trying to undo the nut, even used extended bars, but to no joy..
You can try WD40, or even using some heat direct onto the bolt, this can free it up, basically it has probably seized at one of several points. We even hit the centre with a thin rod to try and free it up. But if it doesn't want to go then it won't. We then had to drill the other side out to break the thread, once the thread is broken you can removed the collar and tap back the long bolt. Basically we started on a 6mm drill bit and worked upto (i think it was about a 16mm to break it!!)
Good luck though, and hope you don't have to go that far...
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