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torque value
- Thread starter bdfbeemer
- Start date
Try this.............
https://www.google.ca/search?q=torq...1.69i57j0l5.9546j1j8&sourceid=chrome&ie=UTF-8
https://www.google.ca/search?q=torq...1.69i57j0l5.9546j1j8&sourceid=chrome&ie=UTF-8
dieselyoda
Active member
Rule of thumb and otherwise pretty accurate.
Buck,
Proper torque is not just a funtion of bolt diameter.
It is also important to consider what material the bolt is going into (steel, iron, aluminum, pot metal, plastic, etc.)
It is important to consider fastner grade (grade 2, grade 5, grade 8 and the metric equivalant in both the bolt AND the nut).
It is important to consider the depth of engagement. Depths of less than approx 1 1/2-2 times thread diameter usually require less torque than standard values.
It is important to consider fastner surface condition (cadmium plated, zinc plated, wet [oil, anti-seize, thread locker, etc.], or dry).
It is important to consider application. There are a myriad of special applications. One is the valve cover bolts on early Kbikes that bottom out on a shoulder on the bolt and go into the very soft aluminum camshaft bearing supports (too tight strips the threads in the cam supports).
Get a manual for the bike in question and follow the specs. for the important fastners. There will sometimes be a generic charts for general fastners in the front of the manual that you should use with caution and consider material, depth, and application.
Proper torque is not just a funtion of bolt diameter.
It is also important to consider what material the bolt is going into (steel, iron, aluminum, pot metal, plastic, etc.)
It is important to consider fastner grade (grade 2, grade 5, grade 8 and the metric equivalant in both the bolt AND the nut).
It is important to consider the depth of engagement. Depths of less than approx 1 1/2-2 times thread diameter usually require less torque than standard values.
It is important to consider fastner surface condition (cadmium plated, zinc plated, wet [oil, anti-seize, thread locker, etc.], or dry).
It is important to consider application. There are a myriad of special applications. One is the valve cover bolts on early Kbikes that bottom out on a shoulder on the bolt and go into the very soft aluminum camshaft bearing supports (too tight strips the threads in the cam supports).
Get a manual for the bike in question and follow the specs. for the important fastners. There will sometimes be a generic charts for general fastners in the front of the manual that you should use with caution and consider material, depth, and application.
Last edited:
Thanks for the comments. I had to loosen the bolts to the protection bars to remove the valve cover. I had all the vlaues in my cheat sheet but I didn't have these. Found what I need in the BMW repair DVD. Takes me a while to find stuff on the DVD. 28 NM for the M8 and 38 for the M10. The Wunderlich instructions just says tighten all the bolts.
I think the Wunderlich installation videos on YouTube tell the appropriate torque. They really should put them on printed instructions as well.
dieselyoda
Active member
If you get so caught up in the exact torque, you don't understand the principals that apply to what the bolt/nut is supposed to do.
You can throw as many factors as you want into a torque value, from dry/lubricated, fine/coarse thread all the way to torque wrench calibration.
Throw is some torque-to-yield, torque-turn and you can make yourself about crazy.
I recently did an exercise with segmented hydraulic valves that required from the OE 90 in/lbs on the tie rod.
I hit 90 +/- 3 in/lbs by hand 9 for ten times trying the exercise. Crappy torque wrenches weren't close. Calibrated torque wrenches yielded 10 for 10, +/- 3 in/lbs.
Young guns weren't close. Top guns were the same as me.
Results using power tools were bad, very bad.
Largely though, the exercise was to understand our problem with valves and our problem wasn't because we were too tight on the tie rod, the problem was the tie rod was inadequate to hold a gang of 12 segments.
But, we knew that.
You can throw as many factors as you want into a torque value, from dry/lubricated, fine/coarse thread all the way to torque wrench calibration.
Throw is some torque-to-yield, torque-turn and you can make yourself about crazy.
I recently did an exercise with segmented hydraulic valves that required from the OE 90 in/lbs on the tie rod.
I hit 90 +/- 3 in/lbs by hand 9 for ten times trying the exercise. Crappy torque wrenches weren't close. Calibrated torque wrenches yielded 10 for 10, +/- 3 in/lbs.
Young guns weren't close. Top guns were the same as me.
Results using power tools were bad, very bad.
Largely though, the exercise was to understand our problem with valves and our problem wasn't because we were too tight on the tie rod, the problem was the tie rod was inadequate to hold a gang of 12 segments.
But, we knew that.
dieselyoda
Active member
Just like watching the tire guy at the local shop hitting the lugnuts until the impact quits turning them.Yoda,
I like the method often accredited to a very famous American motorcycle manufacturer:
"Tighten until the bolt breaks and then back off one quarter turn".
