It's on a Lefty, if that makes a difference.
It's the little hydraulic button type, not a cable.
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The button sticks in in the unlocked position.
Wiggling the damper control knob on top of the fork sometimes gets it to pop back, so I'm guessing the fault is in there, not in the button itself.
Is it likely to be something I can fix without spending [url= http://qwertycycles.co.uk/products/cannondale-xlr-hydraulic-lockout-kh082 ]£120 on the whole assembly[/url]?
Have you tried bleeding it?
check the threshold adjuster barrel is all the way open (+) if that doesnt work then bleed...
Thanks for the advice.
I found
which explains how to do it.
Looks like I need to spend [url= http://www.ebay.co.uk/itm/Rock-Shox-Speed-Lube-Kit-Totem-X-Loc-Series-Fork-Shock-Dual-Syringes-Bleed-Kit-/400530215103 ]£40 on the kit[/url] though, unless anyone knows a cheaper UK source. I can't see it on Qwerty or TF Tuned.