× 12 (EXAMPLE: 5.5 ft-lb × 12 = 66 in-lb), in-lb = Nm × 8.851 (EXAMPLE: 9 Nm × 8.851 = 79.7 in-lb), in-lb = kgf-cm × 0.87 (EXAMPLE: 300 kgf-cm × 0.87 = 261 in-lb). The beam type wrenches use a simple principle of deflection that allows the user to re-calibrate the wrench. Compare them and make your own decision as to which to use. The following table lists general torque specifications for common brands and components. This resistance can be correlated to, but is not a direct measurement of, fastener tension. It is commonly believed that bolts and nuts often come loose for no apparent reason. the earlier specs may be right. They are broken down by Willys Group number, corresponding to the sections of the parts lists that you'll find the fasteners in. Crankshaft | Connecting Rod | Pistons | Lubrication System. The later manuals ('53 & '65) say to use this spec for rubber-bushed spring pivots. If it is pointing to zero on the scale, the wrench is calibrated. The 38-42 ft-lb spec was used throughout WW-II on MB & GPW too, but this figure seems far too low for a differential bearing cap, or ... the earlier specs may be right. Threaded fasteners (nuts and bolts) are used to hold many components to the bike. Common industry practice is resistance at lever half way through swing from open to fully closed. If you use aftermarket performance bolts like ARP's, you should follow the recommended torque specifications. While the bolt may be strong enough, the threads in the cast iron housing may not be.
Another torque unit used in the USA is the foot-pound (abbreviated ft-lb. Torque for mechanics is simply a twisting or turning motion around the axis of the thread. If the pointer is off to either side, the pointer beam can be bent back so it again points at zero. 3) This spec is not found in Willys manuals. Vibration, stress, use, or abuse cannot typically overcome the amount of clamping force in a properly sized and secured threaded fastener. It is easiest to use a lever between the two beams and pry small amounts, checking the scale and the pointer often. Formulas for converting other torque designations into Newton meter (Nm) and inch pounds (in-lb. For more see, Stem binder bolt: Quill type for threaded headsets, Stem steering column binder bolts: Threadless headset types, Stem handlebar binder: 1 or 2 binder bolts, Shimano® Octalink XTR crankarm bolts (M15 thread) (not Hollowtech II), Shimano® Hollowtech II bottom bracket bearing cup (2004 XTR, XT, Dura-Ace), Shimano® Hollowtech II crank bolt screws (2004 XTR, Dura-Ace, XT), Shimano® Hollowtech II Left-hand fixing cap, Crank bolt (including spline-type cranks and square-spindle cranks), Chainring cassette to crankarm (lockring), Brake caliper mount to frame: side/dual/center pull, Brake caliper mount to braze-on: linear pull/cantilever, Brake pad: threaded stud, dual pivot/cantilever/sidepull, Brake cable pinch bolt: linear pull/cantilever, Brake cable pinch bolt: sidepull/dual pivot/centerpull, Straddle wire pinch: cantilever, 5 x 0.8 thread, Brake caliper wire pinch: linear pull/cantilever, M6 x 1 thread, Brake lever: drop bar type (including STI and Ergo types), in-lb = ft-lb. These wrenches rarely require re-calibration.
For bronze bushed pivots, the say to "tighten the retaining nut, after which back it off 2 cotter pin slots", then "be sure the nut is drawn up tight, however, it must be sufficiently loose to allow the spring to pivot freely".
Depending on steel grade, either may be correct. Contact rim manufacturer for specific tension recommendations. See, Measured torque not typically used. A cross-threaded bolt will not properly tighten even with a torque wrench. Torque is typically not used in wheels.
Below is a table of torque equivalents and formulas for conversions follow the torque table. This stretching is not permanent, but it gives the joint force to hold together, called “preload,” or tension. It is possible to convert between the two units by multiplying or dividing by twelve. If the pointer needle is not pointing to zero when the tool is at rest, it is simply bent back until it does align. In other words, the more effort it takes to tighten a bolt, the tighter it is. It is possible to convert between the various systems. See also related article on Basic Thread Concepts. Generally, engineers will specify a thread size large enough to handle the anticipated stresses.
The units given on the torque table here will be the in-lb. Loose bolts and nuts are also generally the source of various creaking on the bike. ), which is the force in pounds along a one-foot long lever. As a fastener is tightened, the fastener actually flexes and stretches, much like a rubber band. Each fastener is designed for a certain range of tension.
This means the weakest part of the joint determines the limits of tension, and hence, torque. The separate pointer beam remains un-deflected, and the primary beam below flexes and moves with the handle. Inspect the pointer when the wrench is at rest. Tension in the fastener depends largely upon the amount of torque (tightening) and the size of the thread. The source of these additional specs is not given, so I cannot vouch for their accuracy, but they seem reasonable. These are 3/8"-24 studs & nuts. AERA Torque Specs 500 Coventry Lane, Suite 180, Crystal Lake, IL 60014 Toll-free Technical Hotline: 1-888-324-2372 (1-88-TECH-AERA) 815-526-7600 fax 815-526-7601