Road Bike, Cycling Forums banner

1 - 8 of 8 Posts

·
Registered
Joined
·
156 Posts
Discussion Starter · #1 ·
I am tightening up a Zipp carbon stem. The bolts (Ti I believe) require 6 N-m torque. I have a Park torque wrench (TW-1), which is in kg-cm units

The conversion is: 1 newton meter = 10.197 kilogram centimeter

so basically 60 kg-cm

but at even 30 kg-cm, when I feel how tight they are with a reasonably long hex key, they seem already very tight. I am just now sure I trust, or rather should trust, the torque wrench. Any tips appreciated as I certainly do not want to damage the stem or, conversely, have my bars slip.

Thank you!
 

·
Registered
Joined
·
308 Posts
I have the same stem and used the tourqe wrench. then checked them with the long allen wrench. they felt nice and snug to me. i could still move the bolts if i had wanted to, but they were not "just barely in there"

i would snug them up and give the bars a nice hard twist. if they don't move you are good. make sure to carry the allen wrench with you, and if they do move, just pull over and adjust them.
 

·
Juanmoretime
Joined
·
2,201 Posts
Use Taxc Dynamic Paste and less torque for slip free grip. I prefer to error on the side of less and the paste allows you less torque and adds grip strength. Why accidentally destroy expensive parts.
 

·
Registered
Joined
·
11,474 Posts
Fun and games.

Not as practical a suggestion than the previous posts, but I find helpful sometimes to remind myself what the numbers stand for. 60 kg-cm is a little awkward to translate into reality, but 6 Nm is also about 52 inch-pounds. This means 52 pounds of force applied at 90 degrees to the end of a 1-inch long lever would get you 60 kg-cm or 6 N-m.

A lever twice as long means cutting the force in half, so a 26-pound push at the end of a 2-inch lever would result in the same torque again. The trick is to find out what a 26-pound push on a hex wrench feels to your finger or thumb . . . :D
 

·
Registered
Joined
·
10,160 Posts
feel...

It only takes a modest twist with a short handled hex wrench or a 4-5-6 Y-style wrench to produce 6Nm of torque. NEVER use a long handle hex wrench on small M5 bolts. It's not necessary. There have been several reports of misread or malfunctioning torque wrenches resulting in over torqued and broken bolts. I never use a torque wrench on small bolts like these.
 

·
Arrogant roadie.....
Joined
·
4,232 Posts
At work, I have access to a torque tool testing machine, and as a result, my torque wrenches are regularly calibrated. But, for those without access to such a machine, just remember that Torque = force * distance. If you want to see what 5 ft*lbs is on a torque wrench, hang a 5 lb weight exactly 1 foot from the center of rotation. If the wrench goes 'click' at just about 5 lbs, then it's calibrated. BTW, in industries such as machine building, calibrations of torque tools is usually ± 15%, so there is a lot of leeway here.
 
1 - 8 of 8 Posts
Top