Some users of the belgium mountainbike forum have problems with there lefty hub.
But nobody knows for sure, is it the OPI spindle or is it the hub (bearing)
So let's check it out...
Opi spindel 25,00mm
Bearing Cannondale (inside) 25,10 mm
Bearing from ebay (5$) 25,10 mm
Bearing SKF 24,95 mm
So why do you have an axial problem with you lefty wheel ?
You can see the SKF bearing is smaller than the other bearing, and this is necessary because you need a press fit !