I've been building my FM1002 / FM1166 - 150mm FRAMED FS frame and am using an EDS OX. This is the 4th of these derailleurs I have mounted on my 29er hardtails. Initially I ran into the derailleur not fitting at all on the UHD used on the frame. I modified the frame and ground the derailleur down some to get the derailleur to fit.
Once I assembled the bike enough to put a chain on, I spent about 2 hours trying to get the EDS OX to shift across the gears. No matter how I adjusted the "B" screw or trimmed the cage, it would not shift down to the 12th, 10 tooth cog. Today I was able to install a derailleur hanger extension and was able to finally get the derailleur to shift through all the gears and shift smoothly.
Close observation of the FRAMED Frame revealed that the UDH sits about 1/2" (12mm) farther back behind the axle center line than the hangers on my other bikes. This positional relationship between the derailleur top pulley and the 10 cog creates a 2" (50mm) open section of chain that flexes too much to allow the derailleur to shift down into the highest cog.
When I added the extender, and then rotated it such that the top cage pulley sits in front of the axle center line, this allows the chain to shift into the lowest gear. I am suspecting that the Design of this frame is at fault where they chose to mount the UDH so it sits farther back behind the axle than it should. SRAM wouldn't do this intentionally would they?
Has anyone else encounter shifting difficulties due to the position of their UDH?