Removing cannondale headshok fork nut?

[sefton1275gt]

nothing seems to be rounded off.

A 6mm key is too big (tried tapping in with hammer)

And a 5.5 is too small

Am I missing something?

 

[My_Teenage_Self]

yeah, that's not a hex! 1, 2, 3, 4, 5...

 

[sefton1275gt]

 

[old_coyote_pedaller]

Any idea what hub that is? The Headshok too for more info, don't recognize the dropout. Not seen a hub bolt like that, I assume it isn't quick release at other end?
Seems unusual that a tool other than a normal hex Allen key would be required to unscrew it. Then again Cannondale did like their many different special tools peculiar to them.

 

[dazzawazza]

I think that's a theft prevention skewer.
I have one of these on one of my bikes purchased from the LBS about 15 years ago..
Here's a pic of the key.

 

[sefton1275gt]

Here you go

 

[d8mok]

It’s a security skewer as mentioned above. Works well it’s seems …

 

[sefton1275gt]

Pentagon key (cheap, so will order some)

 

[old_coyote_pedaller]

So nowt to do with the hub or Headshok but turns out it's a security skewer which is the first of it's type I've ever seen.
As said above , seems to work as intended.