Currently I'm running a Shimano Saint 810 front hub and fork Lyrik coil 20mm. I've a good offer on a brand new Manitou Mattoc 2014. But this fork uses 15mm axle. I'm looking for an adapter to be able to use this fork with the saint 20mm hub. I've looked everywhere, forums, online stores, etc, no luck so far. Seems I will need to change the hub and rebuild the wheel. Any recommendations?
20mm hubs have an axle width of 110mm whereas a 15mm thru axle is 100mm. This means that there is no backwards compatibility on the hub unless it was already designed that way (such as Hope 2 hubs). The M810 is simply too wide.
You would need to replace the front hub at least to run a 15mm TA fork.