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So. Calif.
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Discussion Starter · #1 ·
LBS is assembling a PowerTap Elite-Plus hub (Campy) and alloy rim for me. We went with 28 Sapim Cxray spokes and 2X lacing ... I weigh 165 lbs so 28 was an intentional, slight over-design.

I did not state a preference for trailing spoke, heads In or Out on the wheel -- any strong reason to favor one or the other ?

One argument for head out (elbow inside) is:
" ... Under drive torque, especially in low gear, the trailing spokes straighten out and the leading spokes bend even more. If the wheel is laced with the trailing spokes on the outside of the flange, the crossing gets pulled outward toward the derailer cage, and in some cases will actually hit against the derailer only under load. ..."

ie, he's saying trailing spokes should be heads out & elbow inside.

But a paragraph later Sheldon writes:
" ...This is not an important issue! There is a sizable minority of good wheelbuilders who prefer to go the other way around, and good wheels can be built either way... "

Other RBR threads have indicated Campy builds will have tighter clearance to Rear Der, so the outward flexing on trailing spoke could be a concern, favoring heads out.

However, on Powertap hubs the drive torque is actually transmitted to the left side (opposite cogs), so maybe it's not an issue!

To further confound, Powertap hubs have relatively narrow flange spacing, so trailing spoke head in & elbow out would effectively widen the flange spacing, and reduce lateral wheel flexing.

No doubt the overall workmanship trumps small details like this, but what do you wheelbuilders out there think ?
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