i am wondering if there is an adapter that allows a normal quick release wheel to be used with shocks designed for a 20mm hub eg. marzocchi Z3 w/20mm qr.
I read about it in a magazine but where do you buy them? or maybe they don't exist at all!
I am aware that buying a 20mm hub and building it into your wheel is the way to go as there are great advantages to be had with wheel stiffness, but any info about these adapters will be greatly appreciated.
The only adapters that I have seen are for converting a regular thru-axle 20mm hub into a QR.20 (Marzocchi) style hub.
You can't easily convert a regular hub to the QR.20 since the spacing on a QR.20 hub is wider than a regular front hub.
Your only really choice is to build a new wheel using a QR.20 hub (or a regular 20mm thru axle hub with the Marzocchi adapter). And as you said, if you were to adapt a regular hub to fit your fork, you'd lose the increased stiffness that a 20mm axle hub/fork combo gives you.