Technical Tips

Tightening Torques & Widths Across Flats

Here you will find the tightening torques and spanner widths of the most common inch and metric screws on your bike. These specifications always refer to strength class 8.8 and the combination “steel-in-steel”, i.e. steel screw in steel housing.

Inch Screws

Thread in InchesThread in MillimetresUNCUNFTightening Torque in NmWidth across Flat in Inch
1/46,35202887/16
5/167,941824161/2
3/89,531624259/16
7/1611,1114204511/16
1/212,701320753/4
9/1614,291218807/8
5/815,88111815015/16

Metric Screws

Thread in MillimetersTightening Torque in NmWidth across Flat in Millimeters
M42,97
M568
M61010
M82513
M104917
M128619
M2255032
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