ISSEY MIYAKE SILAN003 - Replacing bizarre spring bars & strap

[JRock]

I had this watch for a while and love it. I'm just getting into watch maintenance and repair and decided to change the strap -- I've changed many straps and bracelets, and I've even graduated to converting regular straps to quick release. But this thing is bizarre. The original strap just slips off, while the spring bars (are they even spring bars?) remain attached (and is the strap supposed to just slip off?). No idea how to proceed. 

[Simeon]

That's a single lug / integrated strap design.  The Vostok Amphibia Neptune is another that springs to mind.  These can be fitted with swinging strap adaptors that allow a standard 18mm strap to be fitted.  

Some people adapt steel bracelets to fit by removing the end links or spreading / bending the side pieces of a link to fit around the lug.

I would imagine that your strap slips off the pins  because the strap layers are separating and providing too much clearance around the pins.  Some contact adhesive and pinching the loops closer to the pin (bulldog clips?) while it dries would probably stop it.

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