Is there any way to bond cycle wings to the stays or do they have to be bolted?

Ta

some have bonded them using sikaflex type adhesives i gather.

EvoStick Liquid metal (dries silver) or Ultimate adhesive (dries white.)
Both available at B&Q.
Theres nothing like a bi of bondage of yer stays

We used 3M PU adhesive to bond front cycle wings to stays. They were still attached after the accident we had, even though the stays were trashed. Just make sure you prepare the surfaces properly and you'll have no problems.

Phil

Is this the stuff? If so I can add to me order.

Yep, that'll do the trick.