Torque Wrench
01-18-11 | 09:57 AM
#26
Torque specs are so that threads on the aluminum bits don't get stripped. Has nothing to do with carbon bits being crushed.
Think about it... why would the torque spec, supposedly for, say, protecting a carbon steering tube, be printed on the stem? The stem doesn't know what steering tube it's going to be attached to when it leaves the factory. It's printed there so you don't strip the screw threads out of the stem. Has nothing to do with the steering tube. Ditto on the other bits that have torque specs written on them.
You can achieve the same thing by learning how to tighten screws without stripping the aluminum threads. You protect the carbon bits by not be so overzealous with the torque. Tighten just enough that things don't move when in use. No more, no less. If a joint is held by multiple bolts, make sure to tighten each bolt evenly. Quarter turn on one bolt; quarter turn on another. Work your way around so the stress on each bolt never varies too much. This is important always, but is extra important with the carbon bits. Much more important than torque specs.
And if your seatpost keeps slipping even after tightening things down, you likely need a shim. For God's sake, don't just continue reefing on the thing. Seems like most carbon bikes do, nowadays; the seat tube is so thin the manufacturers have less dimensional control over it. You can't risk the seat tube ID being less than the seatpost diameter, so they err on the larger side.
Think about it... why would the torque spec, supposedly for, say, protecting a carbon steering tube, be printed on the stem? The stem doesn't know what steering tube it's going to be attached to when it leaves the factory. It's printed there so you don't strip the screw threads out of the stem. Has nothing to do with the steering tube. Ditto on the other bits that have torque specs written on them.
You can achieve the same thing by learning how to tighten screws without stripping the aluminum threads. You protect the carbon bits by not be so overzealous with the torque. Tighten just enough that things don't move when in use. No more, no less. If a joint is held by multiple bolts, make sure to tighten each bolt evenly. Quarter turn on one bolt; quarter turn on another. Work your way around so the stress on each bolt never varies too much. This is important always, but is extra important with the carbon bits. Much more important than torque specs.
And if your seatpost keeps slipping even after tightening things down, you likely need a shim. For God's sake, don't just continue reefing on the thing. Seems like most carbon bikes do, nowadays; the seat tube is so thin the manufacturers have less dimensional control over it. You can't risk the seat tube ID being less than the seatpost diameter, so they err on the larger side.
I have been turning wrenches a long time and really don't need one for small stuff but still will take it out once in a while.
I also want o add do yourself a big favor and get some carbon assembly paste and use it! brand not important just use it on your carbon bits and you will not need to over tighten to keep things in place.
__________________
It may not be fancy but it gets me were I need to go.
https://www.jtgraphics.net/cyclist_bicycles.htm
It may not be fancy but it gets me were I need to go.
https://www.jtgraphics.net/cyclist_bicycles.htm
01-18-11 | 10:34 AM
#27
Senior Member
Joined: Jun 2002
Posts: 6,655
Likes: 2,253
From: Montreal, Quebec
I may have missed it, but one thing I have not seen in this thread is the point that there is usually a fairly wide range of torque for a bolt, say 6-8 nm. What is really important, and what you can't do by hand is to tighten all clamp bolts to exactly the same torque. This is important so that all the bolts are under the same load. When I tighten clamp bolts on my steer tube I do each one 3 times, and each time the bolt tightens a bit more, you can't possibly tighten bolts by hand and get them to exactly the same torque, which you can do with a torque wrench.
01-18-11 | 10:42 AM
#28
Senior Member
Joined: Dec 2001
Posts: 1,174
Likes: 6
From: Downey, CA.
Bikes: Litespeed Classic (55cm), Specialized Tarmac Pro (56cm)
The sale $49.99 Nashbar kit is the same one as the Performance on sale at $69.99, just with the Nashbar logo instead of Spin doctor. I took took advantage of the 20% (5 items) yesterday too, which was extended into today. So the resulting $40 for that style torque wrench with the hex bits in a case....well if anyone is in the market that seems like the way to go.
However from the reviews, just know that once at torque it doesn't click, the head flexes in the handle. One reviewer said once he figured that out it works perfect. Some of the bad reviews were from not knowing how it worked.
However from the reviews, just know that once at torque it doesn't click, the head flexes in the handle. One reviewer said once he figured that out it works perfect. Some of the bad reviews were from not knowing how it worked.
Yeah, for $40 that is pretty hard to beat.
__________________
Litespeed, lasts a lifetime.
Specialized Tarmac, lasts a lifetime, or until it breaks.
Litespeed, lasts a lifetime.
Specialized Tarmac, lasts a lifetime, or until it breaks.
01-19-11 | 12:36 AM
#30
pan y agua
Joined: Aug 2005
Posts: 31,812
Likes: 1,233
From: Jacksonville
Bikes: Willier Zero 7; Merlin Extralight; Calfee Dragonfly tandem, Calfee Adventure tandem; Cervelo P2; Motebecane Ti Fly 29er; Motebecanne Phantom Cross; Schwinn Paramount Track bike
Torque specs are so that threads on the aluminum bits don't get stripped. Has nothing to do with carbon bits being crushed.
Think about it... why would the torque spec, supposedly for, say, protecting a carbon steering tube, be printed on the stem? The stem doesn't know what steering tube it's going to be attached to when it leaves the factory. It's printed there so you don't strip the screw threads out of the stem. Has nothing to do with the steering tube. Ditto on the other bits that have torque specs written on them.
You can achieve the same thing by learning how to tighten screws without stripping the aluminum threads. You protect the carbon bits by not be so overzealous with the torque. Tighten just enough that things don't move when in use. No more, no less. If a joint is held by multiple bolts, make sure to tighten each bolt evenly. Quarter turn on one bolt; quarter turn on another. Work your way around so the stress on each bolt never varies too much. This is important always, but is extra important with the carbon bits. Much more important than torque specs.
And if your seatpost keeps slipping even after tightening things down, you likely need a shim. For God's sake, don't just continue reefing on the thing. Seems like most carbon bikes do, nowadays; the seat tube is so thin the manufacturers have less dimensional control over it. You can't risk the seat tube ID being less than the seatpost diameter, so they err on the larger side.
Think about it... why would the torque spec, supposedly for, say, protecting a carbon steering tube, be printed on the stem? The stem doesn't know what steering tube it's going to be attached to when it leaves the factory. It's printed there so you don't strip the screw threads out of the stem. Has nothing to do with the steering tube. Ditto on the other bits that have torque specs written on them.
You can achieve the same thing by learning how to tighten screws without stripping the aluminum threads. You protect the carbon bits by not be so overzealous with the torque. Tighten just enough that things don't move when in use. No more, no less. If a joint is held by multiple bolts, make sure to tighten each bolt evenly. Quarter turn on one bolt; quarter turn on another. Work your way around so the stress on each bolt never varies too much. This is important always, but is extra important with the carbon bits. Much more important than torque specs.
And if your seatpost keeps slipping even after tightening things down, you likely need a shim. For God's sake, don't just continue reefing on the thing. Seems like most carbon bikes do, nowadays; the seat tube is so thin the manufacturers have less dimensional control over it. You can't risk the seat tube ID being less than the seatpost diameter, so they err on the larger side.
I agree a torque wrench really is not needed but some people just don't have a fill for tightening bolts! I know I have seen it
I have been turning wrenches a long time and really don't need one for small stuff but still will take it out once in a while.
I also want o add do yourself a big favor and get some carbon assembly paste and use it! brand not important just use it on your carbon bits and you will not need to over tighten to keep things in place.
I have been turning wrenches a long time and really don't need one for small stuff but still will take it out once in a while.
I also want o add do yourself a big favor and get some carbon assembly paste and use it! brand not important just use it on your carbon bits and you will not need to over tighten to keep things in place.
I have a torque wrench but I rarely bother to use it.
I've built bikes up from the frame, and installed lots of stems and handlebars, without using a torque wrench, and never cracked a carbon component.
Use carbon assembly paste, and tighten the bolts snug enough so things won't slip and you'll be fine.
One thing to realize is that the specs on bike components are for maximum torques. So it's not like you have to hit a precise torque range. You only have to tighten the bolt enough to hold without exceeding the maximum tourque. With a little experience, touch, and judgement, you can do this without a torque wrench.
__________________
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
