Optimal 1x chainline?
06-14-23, 03:28 PM
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Optimal 1x chainline?
I am building up a 12 speed 1x bike.
Curious about optimal chain to pursue. I don't have tire or frame clearance issues to worry about so I could use the Sram Force regular or wide cranks.
One would give me 45mm and the other 47.5mm. I can choose either, but curious if anyone has first hand experience regarding smoothness and noise.
Thanks
Curious about optimal chain to pursue. I don't have tire or frame clearance issues to worry about so I could use the Sram Force regular or wide cranks.
One would give me 45mm and the other 47.5mm. I can choose either, but curious if anyone has first hand experience regarding smoothness and noise.
Thanks
06-14-23, 03:57 PM
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I do not have a bike with a 12-speed drive train, but my understanding is that the optimal 1x chain line is one that is both [1] parallel to the longitudinal axis of the bike (i.e., the axis of the top tube) and [2] lines up exactly with the center of (the width of) the cassette. If you use one side of the cassette significantly more than the other, then you can move the chain line by a few mm (but, generally, not by more than one cog) to favor the more frequently used side of the cassette. All of the above assume that there is sufficient clearance between the chain ring and chain vis-a-vis the frame.
06-14-23, 07:38 PM
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No personal experience here, but would imagine it depending on the rear hub spacing and also whether you want to be slightly biased towards the bigger or smaller cogs.
06-21-23, 10:45 AM
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It is difficult to measure (even though I have a surface plate, bottom bracket post and height gauge), but I get the center of a SRAM 12 speed XPLR cassette at 42mm - 42.5mm from the centerline of the frame.
Also according to this wolftooth website posting, it seems as though ideal chainline (according to wolftooth) is to add an extra 2mm from the center of the cassette. That would equal about 44.5mm
https://www.wolftoothcomponents.com/...and-chainrings
I am going to choose the regular SRAM crankset that has the 1x chainring at 45mm
Also according to this wolftooth website posting, it seems as though ideal chainline (according to wolftooth) is to add an extra 2mm from the center of the cassette. That would equal about 44.5mm
https://www.wolftoothcomponents.com/...and-chainrings
I am going to choose the regular SRAM crankset that has the 1x chainring at 45mm
06-21-23, 11:34 AM
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It's not picky. SRAM has some "Wide" road cranksets that are 47.5, and their MTB non-boost cranks were 50
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06-21-23, 01:14 PM
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It is difficult to measure (even though I have a surface plate, bottom bracket post and height gauge), but I get the center of a SRAM 12 speed XPLR cassette at 42mm - 42.5mm from the centerline of the frame.
Also according to this wolftooth website posting, it seems as though ideal chainline (according to wolftooth) is to add an extra 2mm from the center of the cassette. That would equal about 44.5mm
https://www.wolftoothcomponents.com/...and-chainrings
I am going to choose the regular SRAM crankset that has the 1x chainring at 45mm
Also according to this wolftooth website posting, it seems as though ideal chainline (according to wolftooth) is to add an extra 2mm from the center of the cassette. That would equal about 44.5mm
https://www.wolftoothcomponents.com/...and-chainrings
I am going to choose the regular SRAM crankset that has the 1x chainring at 45mm
