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Old 08-20-11, 09:08 PM   #1
newyorkcity
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Torque on Stem / Faceplate

When reinstalling a threadless stem and faceplate, is it necessary, in terms of safety, to use a torque wrench? I generally use a sharp increase in resistance as an indication of tightness, though I suppose that this method might not be appropriate... particularly when using carbon components.
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Old 08-20-11, 09:24 PM   #2
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As important than the final torque, if not more so, is the sequence of tightning, and keeping both upper screws and both lower matched as pairs. When kept matched each screw does half the work, but if not matched it's easy to over tighten or stress the tighter bolt.

As far as the torque wrench goes, I'm more a believer in calibrated fingers and awareness of how the torque is ramping up as I come to working tightness. Also keep in mind that some stems that don't have thread inserts will have lower torques limits than you'd expect based on screw diameter.
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Old 08-20-11, 09:37 PM   #3
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I bought one of these - preset torque wrench that tightens to 5N-m. http://www.jensonusa.com/store/produ...y.aspx?sc=FRGL

Concur wiht FBinNY - important to make sure each shares the load. I usually tighten in a cross pattern, a little each time. I may do three passes (light, medium, medium hard) before the final torqueing.

EDIT- added web site.
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Old 08-20-11, 10:14 PM   #4
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Originally Posted by MudPie View Post
Yea, I've seen this before but its unfortunate that it isn't adjustable... has anyone ever seen an adjustable torques wrench in this format?

Better off getting this for another $10 with a range of 0-100nm:

http://www.sears.com/craftsman-torqu...p-00944978000P
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Old 08-20-11, 10:25 PM   #5
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For carbon stuff, using a torque wrench might be more important. But I can't say for sure. The only thing I use a torque wrench for is tightening cranksets. I've already ruined one by leaving the bolts too loose and I don't plan on doing that again. But once I learn what ~40ft-lbs feels like I'll probably just do without.
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Old 08-20-11, 10:42 PM   #6
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Not only for carbon, I have a 3T alloy stem with TI bolts and torqued to max specified and "ping" broken bolt. I replaced with stainless. I use a torque wrench and don't go quite to max torque either.
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Old 08-20-11, 11:57 PM   #7
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carbon components definately have torque specs. I use an adjustable torque wrench on my seatpost clamp, and stem bolts. My fsa carbon over alum neck has the spec printed directly on it. ypou can just barely see it between the 2 lower bolts
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