Torque settings

[MBosh]

I just recently purchased a torque wrench so that I could use the right torque on my bike, but I'm confused about these setting on a website? What do these 3 things mean (below)? Am I suppose to tighten what I'm tightening anywhere between 5-7 Nm and whats the 43-61 lbs mean?

Shimano®

5~7 Nm

43~61 in lbs

This is the torque for the cassette lockring (below) so do I tighten the lockring anywhere between 29.4 - 49 Nm?

Shimano®

29.4~49 Nm

260~434 in lbs

 

[figbat]

Yes, you can tighten to anywhere in the range given. They are given in two units: metric (N.m) and Imperial (in.lb .... inch-pound).

 

[Profpointy]

From your question, It's perhaps worth explaining what the numbers mean. So many foot pounds means a force equivalent to that number of pounds weight applied to the end of a spanner a foot long or one pound weight acting at right angles to a spanner that number of feet long.

1 foot pounds = 12 pound inches

A Newton is the SI force unit. A kilogram weighs about 10 Newtons (9.81). Thus 10 Newton metres is the weight of a kilogram turning a 1m long bar - which is quite a lot.

If you're unfamiliar with the Newton it is the defined as the force needed to accelerate a mass of 1kg by 1 meter per second every second the force is applied. The force of gravity on earth means a kg weighs 9.81 Newtons - mass being a fundamental property rather than being related to things being on Earth. The equivalent unit in the imperial system is the poundal - the force needed to accelerate a pound by 1 foot per second each second. I've rarely seen it used; they tend to use pounds - which is actually pounds-force - the weight of a pound on Earth. You sometimes see kg-force rather than Newtons too.

From your question I inferred, perhaps wrongly, that you were a bit unclear on the underlying concept, so apologies if I'm teaching my grandmother to suck eggs and been a bit long winded

EDIT - corrected from my original which had a hugely embarrassing goof

 

[rrarider]

From your question, It's perhaps worth explaining what the numbers mean. So many foot pounds means a force equivalent to that number of pounds weight applied to the end of a spanner a foot long or one pound weight acting at right angles to a spanner that number of feet long.

1lbs inch = 12 foot pounds

A Newton is the SI force unit. A kilogram weighs about 10 Newtons (9.81). Thus 10 Newton meters is the weight of a kilogram turning a 1m long bar - which is quite a lot.

If you'r unfamiliar with the Newton it is the defined as the force needed to accelerate a mass of 1kg by 1 meter per second every second the force is applied. The force of gravity on earth means a kg weighs 9.81 Newtons - mass being a fundamental property rather than being related to things being on Earth. The equivalent unit in the imperial system is the poundal - the force needed to accelerate a pound by 1 foot per second each second. I've rarely seen it used; they tend to use pounds - which is actually pounds-force - the weight of a pound on Earth. You sometimes see kg-force rather than Newtons too.

From your question I inferred, perhaps wrongly, that you were a bit unclear on the underlying concept, so apologies if I'm teaching my grandmother to suck eggs and been a bit long winded

1lbs inch = 12 foot pounds - that is just plain WRONG, 1 foot pound = 12 pound inches is correct

The correct spelling of the SI unit of length is metre. A meter is the the thing in your electricity supply cupboard, next to the distribution board

 

[Profpointy]

1lbs inch = 12 foot pounds - that is just plain WRONG, 1 foot pound = 12 pound inches is correct

The correct spelling of the SI unit of length is metre. A meter is the the thing in your electricity supply cupboard, next to the distribution board

Duh, dunno what I was thinking there - you are of course quite right !
I'm going to edit it as it's too embarrassing to let that stand