Technical Dura Ace 7900 SRM Question

Discuss light weight issues concerning road bikes & parts.
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by baldkingpin

The four torx (i.e., starnuts) that secure the crank arm to the PM are supposed to be torqued to 8NM (actually, one of the four is smaller and has a 6NM rating). I'm having difficulty getting my torque wrench in there as the socket bumps against the crank spindle, causing the torx bit to not align well. This is especially a problem with the small starnut as it's fragile and shallow.

I've managed to get them right by using an extension but it's sure awkward and I can see there's a high risk of rounding the starnuts if you're not ultra careful. The four pin fastener on my old Cannondale SRM was a way better system. I suspect clearance issues with new frames led to the new design for Dura Ace.

Anyone run into this issue? What tool do you use? Thoughts?

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by Cyco

Under the Blue-Point name Snap-On does long Torx bits
Success is how far you you bounce back up after being knocked down

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by thisisatest

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