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Discussion Starter · #1 ·
Can someone explain to me how the offset on front derailleur direct mount adapters is measured? I think I have the wrong offset but don't understand how they are measured.

I picked up a 9:zero:7 Tundra. I finally got a SRAM GX 2x10 high direct mount, top pull derailleur. My LBS sent me home with an Origin8 100mm BB adapter. I'm running the same cranks that were on my previous bike with 197 rear. When I mounted up the adapter and derailleur I can't get it to swing out far enough to hit the big ring. I backed off the limit screw all the way and it still won't swing out far enough. The Origin8 adapter said online it's 85mm spaced. Problem Solvers are 39.5mm (3x), 43.5mm (2x), Moonlander (unspecified), and Wofltooth/Borealis is 50mm. I thought it was from the outside of the seat tube but then the Origin8 at 85mm didn't work with the math.
 

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Hi. Did you ever solve this? I am running into the exact same problem. 100mm BB, 197mm rear hub, moving drivetrain from old frame over to a new frame with same BB and rear hub spec. I had to buy a new high direct mount front derailleur and Origin8 100mm direct mount adapter. I have made things work by moving all the BB spacers to the non-drive side and then maxing out the limit screws. But the crankset is no longer centered on the frame and it seems weird. I started a thread.
 

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Discussion Starter · #3 ·
Hi. Did you ever solve this? I am running into the exact same problem. 100mm BB, 197mm rear hub, moving drivetrain from old frame over to a new frame with same BB and rear hub spec. I had to buy a new high direct mount front derailleur and Origin8 100mm direct mount adapter. I have made things work by moving all the BB spacers to the non-drive side and then maxing out the limit screws. But the crankset is no longer centered on the frame and it seems weird. I started a thread.
I ended up with a wider spaced mount. I think the package said it was a Surly OD adapter that my local shop had in stock. You could also try the front mount adapter that Borealis sells. It's under components->small parts. I don't use mine anymore since I've now gone 1x.
 

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Thanks for the update! I have actually gotten over my issue with the offset cranks. Things work, they actually shift quite well. It was just one of those situations where things didn't go together exactly how I imagined they would, but it is working well so I'm rolling with it. I don't notice the few millimeter offset from centered at all when riding.
1929007
 
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