[chuck]

Hi, great post. Not trying to nit pick you here though but just thought you might want to know for your own information...

For torque, "ft/lbs" is an incorrect way to denote the English units for torque as it implies division.

Torque is a force multiplied by a distance, called the moment arm, from the axis of rotation. So you are multiplying a ft by a pound-force or vice versa, it means the same thing - coincidentally you could say meter-Newtons or lbf-ft.

Note how I denoted the lb force there as lbf. This is customary to distinguish the pound-force, which is a unit of force obviously, over a pound-mass, a unit of mass.

edit:

So if you want, the non-SI torque should be lbf-ft or ft-lbf, whichever is fine due to the communicative property of multiplication, but ft-lbf is more customary since when talking about torques people like to keep the moment arm at 1 ft to just isolate the magnitude of the force itself. I.e. a torque from a moment arm of 2 ft and a force of 8 lbf is the same as a torque with a moment arm of 1 ft and 16 lbf. Like how when breaking loose a lugnut you use a long breaker bar, the mechanical advantage of that longer tool. The longer the handle or cheater bar the larger the torque produced with the same force.

 

[chuck]

I don't think a single person would take it as you have, implying division (you must be an engineer or something along those lines). I've never seen an extended torque wrench, so I doubt anyone is connecting an extension to their torque wrench. It was simply the neatest way to make the post with hypens separating all the important information. The BBCode on this site is very limiting.

7.5 ft/lbs - 10 Nm looks better than 7.5 ft - lbs - 10 Nm or 7.5 ft-lbs - 10 Nm.


I even made sure to put a handy key in the first post in case anyone was confused:

ft/lbs = Foot Pounds - Nm = Newton Meters

It's up to you. I just wanted to do a little PSA I guess.

Not sure what you mean by an extension to a torque wrench. I was just describing how a torque works. Any time you are applying a force about a rotational axis you are applying a torque, whether that's a chain driving a sprocket, your hand rotating a screwdriver, or a you pushing on a breaker bar to bust a lug nut loose. A torque wrench is just a way to measure the torque being applied to the fastener or bolt.

 

[chuck]

OK Chuck. I'll bite.
After your post, I have referred to Wikipedia, and perhaps you are simplifying your story to much and have added to the confusion.

Foot - Pounds (Ft -Lbs) is a measure of Work, meaning horsepower.

It was called Ft-Lb-Force in olden days to clarify whether HP or Torque was being the subject of the term being used in the argument, but not now.
1 sturdy English Clydesdale was expected to raise 550 Pounds at a rate of 1 Lb per second. This is 1 English horsepower.

Pound(s) - Feet (Lb - Ft), is the measure of Torque.
Newton - Metres (N-M), is the equivalent in SI, but the common thing is the length of the moment is placed last in the expression.

And there are numerous references with the / used, rather than a -, all over the web.

There is a rather good web page at Foot-pounds and pound-feet—what’s the difference? | Mac's Motor City Garage written with an American slant, that explain in workshop mechanic words better than I can.

Rob.

No worries. The only thing you're biting is some newfound knowledge my friend.

As far as units go - a unit is something like a foot, a meter, a newton, a lbf, etc - torque and work are the same in units but they are not the same in the concept they represent. This is confusing for many people and rightfully so.

Again. They are both a unit of distance multiplied by a unit of force. But they are not the same idea. If you are familiar with some math, a torque is a vector (the magnitude and directional component) while work is a scalar quantity (magnitude or the amount only).

A force applied a linear distance is work. Work is not power. Unit work (or unit energy) per unit time is power. That would be a lbf-ft/sec or ft-lbf/sec. Here is where you get to use the forward slash. It doesn't matter which way you put the lbf or the ft because in the communicative property of multiplication holds. The order comes from convention and even still there are many people that pronounce it either way. As you mentioned, a single horsepower is 550 lbf-ft per second, which is also equal to 33000 lbf-ft per minute, or any other way you would want to specify it so long as you keep the ratio the same, because that's all it is, a rate of work.

In our motorcycles that work is translated to torque. When talking about wheel horsepower, the torque on the dyno is the torque that engine is producing to the wheel at that instant. If you know the torque and you know the RPM, then you can easily calculate power or vice versa. If you know any of the two you know the third.

Work itself does not have a time component. It is merely lbf-ft. Worth noting is that energy also has the same units as work, but they are also a little different but more interchangeable.

What differs a torque from work is how the force is being applied and what the distance means. A torque is a force being applied about a rotational axis with a moment arm of some distance.

If you see torque being described as a ft/lb or a lb/ft, that's just simply wrong and why I decided to point it out. Please don't take offense as I'm just trying to explain.

 

[chuck]

Hi,

Just want to add to this. I've installed some frame sliders on the bike and I was able to obtain the engine mount torque specs from the service manual. These are for the two top engine mounting bolts only (per side). The left or right descriptions refer to the left or right side of the bike as you are in the seat. The bolts on the left side of the engine are shorter than those on the right (45mm on left, 55mm on right).

Again, these specs are for the 2 bolts on each side of the area of the frame that resembles an upside-down Y or yoke. My frame sliders (Shogun) were pictured installed on the rear upper bolt positions. I used a T50 to break them loose.

Torque specs:

==
Engine mounting bolt (Front upper, Left) - 55 N·m (5.6 kgf-m, 40.5 lbf-ft)
Engine mounting bolt (Front upper, Right) - 55 N·m (5.6 kgf-m, 40.5 lbf-ft)
==

==
Engine mounting bolt (Rear upper, Left) - 55 N·m (5.6 kgf-m, 40.5 lbf-ft)
Engine mounting bolt (Rear upper, Right) - 55 N·m (5.6 kgf-m, 40.5 lbf-ft)
==

 

[chuck]

There is a diagram of engine mount bolts and their torque values in post #12 .

My mistake then, I only saw the ??? for several values on your main post - so you should update if you can. I'm guessing there is an edit time limit or something in which case a mod should let you update it.

Feel free to include the torque numbers for the bolts people will be using to install frame sliders so they don't have to deal with the rather incompetent diagram.

 

[chuck]

I did get the thread "stickied." And I've asked a few times if I could be a mod just to keep things tidy around here and merge threads, etc. But admins say they're just forwarded my request to someone and I've never heard anything else.

That's really weird to be honest. Is this forum just an ad-revenue generator?

 

[chuck]

Yep

Initially forums were owned and setup by an individual with an interest in that topic and they managed it as required with pride, not anymore

So we're a fake community apart of someone's quaint portfolio of 'moneytree' forums.

That's no good, it's incredibly cheap to buy a domain and a virtual private server to run a forum on. Talking like $20 bucks a year. Sounds like something should be done lest we continue to be milked for what little our clicks are worth.