Technical Dura Ace 7900 SRM Question

Discuss light weight issues concerning road bikes & parts.
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baldkingpin
Posts: 232
Joined: Tue Mar 20, 2007 5:07 pm
Location: Palo Alto, CA

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?

by Weenie


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Cyco
Posts: 1903
Joined: Sat Nov 30, 2002 4:49 am

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

thisisatest
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Joined: Sat Jun 13, 2009 4:02 am
Location: NoVA/DC

by thisisatest


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