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GlobalRider
02-23-2009, 05:50 PM
Paul, can you say how good/bad the torque values are in the BMW RepROM materials?

I put one together on a spreasheet using the BMW Owner's Manual (a few common torque values), the Haynes, the Clymer and the Chilton manuals for my R100 GS.

Some were way off, but looking at the fastener, you could tell which one was in error.

GlobalRider
02-24-2009, 12:32 AM
Don't forget most clicker type wrenches need calibrating every so often
max

Not just clicker types...anything that makes a measurement needs to be recalibrated and that would include a strain gauge digital torque wrench.

PGlaves
02-24-2009, 04:42 AM
Paul, can you say how good/bad the torque values are in the BMW RepROM materials?

I have only found one clear error in a factory manual (paper or CD) over the years. It was a swingarm pivot pin value on an Oilhead if I recall correctly.

But - translation from ft.lb. to nm. or the reverse can mess up manual writers - so be aware of normal values for typical fastener sizes. This doesn't help with oddball stuff like the Paralever pivots for sure, though.

By the way - overtorquing the flat headed fixed pivot will shear the head off so clean it looks like it was cut with a tool.

henzilla
02-24-2009, 09:16 PM
By the way - overtorquing the flat headed fixed pivot will shear the head off so clean it looks like it was cut with a tool.


I worry about those for sure...even removing after heating makes me cringe until they start moving!

ANDYVH
02-27-2009, 10:04 PM
Like others have said, on any of the "clicker" style or electronic torque wrenches, back them off to relax the spring in the clicker device in the wrench.

NEVER use a torque wrench as a breaker bar.

Once the torque wrench "clicks" there is NO gain in making it click again or for giving it "that extra nudge".

Know the difference between "dry applied torque" and "lubed or wet applied torque". Generally, any type of lube, oil, grease, anti-sieze, probably even Lok-Tite (if too much is used) will reduce the effort applied to make the wrench "click", but the result will be that for the same setting, a "wetted" torqued assembly will be at higher applied torque than a "dry" torqued assembly. If you use lube on the threaded connection, decrease the torque setting by at least 5%.

Always torque the assembly for the weakest material in the connection. Meaning, a 10mm steel bolt threaded into steel threads takes higher torque than the same steel bolt threaded into aluminum threads, or brass threads. Reduce the torque setting, by as much as 40% to avoid stripping out the threads in the weaker material.

GlobalRider
02-27-2009, 10:41 PM
Once the torque wrench "clicks" there is NO gain in making it click again or for giving it "that extra nudge".

Thats because you have to overcome the "static" friction to get the fastener moving again...exactly why it takes more force to initially move a crate than it takes to keep it moving.

I'll go in two or three evenly spaced torque stages on things like wheels...where multiple fasteners hold down something like a cylinder head, etc.