Bolt, Stud, and Torque Information

Contains information about bolts, nuts, terminology, and torques for common fasteners on BMWs.

Information

Below are some links which provide common information about bolts and nuts:

Bolt Joint Information

Bolt Terminology

Bolts, Nuts, Washers

Removing Stuck Fasteners

Fastener Size Reference Tables

Basic Metric Thread Chart

Common Torques

Mike V. (#30064) has compiled a list of torque values for the R100/7. These values are applicable to a wide range of years and models of Airheads. Before using any values in this chart, be sure and consult additional sources such as BMW repair manuals and aftermarket manuals. In addition, ensure that your torque wrench is properly calibrated and you know how to use it. This chart is to be used at everyone’s own risk and is intended as a guide only.

Note: most fasteners are torqued dry, that is no lubricant is used. However, some fasteners do require lubricant (eg, oil) or even loctite. Lubricants can increase the actual torque approximately 15% to 30%. Care must be taken in tightening a fastener where a lubricant is used to ensure that the actual torque in the joint is not exceeded. Torque is a measure of the sliding friction between two surfaces. Lubricants reducing this sliding friction so that a joint may be tightened more than desired.

Metric Stud Explanation

Alex has provided this file as an explanation of parameters associated with metric studs. Since these types of fastening systems are used on our bikes, this will serve as a good reference. It is from the Maryland Metrics company.

Metric Bolt Markings and Torque Values

Here's another refrence to bolt head markings. This will let you confirm the strength of the bolt being used in a particular situation.

Bolt Head Markings

More Metric Bolt Markings and Torque Values

These are taken from the R65 repair manual.

http://www.bmwr65.org/htdocs/yabbfiles/Attachments/torques.pdf

Another Table of Torque Values for Dry and Lubed Fasteners

http://www.cncexpo.com/MetricBoltTorque.aspx

Here's another table for what appears dry torque:

https://www.boltdepot.com/fastener-information/bolts/Metric-Recommended-Torque.aspx

iPhone App to Measure Bolts

Ran across this app from iTunes that lets you compare a bolt for size and thread pitch.

https://itunes.apple.com/us/app/wonderbolt/id873989562?mt=8

Conversion Utilities

Websites for converting units:

http://www.numberfactory.com/nf torque.htm

http://www.onlineconversion.com/