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Does torquing really make a difference and if it does, HOW? It seems to me that getting the bolt tight would be good enough. I'm sure you guys can explain to me why I need to go buy a torque wrench. As you can tell Fred's videos are in my library and one day I might get enough nerve to do something besides change the windshield. Thanks
 

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Most bolts and fasteners in specific locations are designed to be tightened to a specific torque value. What you deem tight may be much more or less than the next person, and it may be "over-tight" depending on the material it is constructed from, continuous excessive tightening can cause premature failure. Tightening to the prescribed torque value reduces the chance of stripping out a bolt or leaving it too loose.
 

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Does torquing really make a difference and if it does, HOW? It seems to me that getting the bolt tight would be good enough. I'm sure you guys can explain to me why I need to go buy a torque wrench. As you can tell Fred's videos are in my library and one day I might get enough nerve to do something besides change the windshield. Thanks
It's all about how a bolt actually works. It's a spring. As you tighten it down into the threads, and the head comes to a stop at the surface, the bolt actually stretches. When it does, it acts like a very strong spring holding the parts together. At some point, the yield point, the bolt will stretch permanently. Oops. In a poorly designed joint, or one that simply can't be well designed, you might strip the female threads first.

So, if you tighten the bolt to say 25% of the yield point, you're only getting 25% of the possible force holding things together. If you get to 101% of the yield point....

Torque specs are designed to get you to about 80% of the yield strength. Strong, but the bolt still springs back as you loosen it. A well torqued bolt can startle people when it does. You'll lean on the wrench, nothing happens and then, sproing, it loosens. At that point, you should be able to spin it out easily by hand, since the spring force is gone.

So, the purpose of the torque wrench is to give you a strong, reusable fastener. Note that measuring torque is an approximation for measuring stretch. If the threads are corroded or dirty, or oiled when they should be dry, or vice versa, or leave off a washer, you'll have different thread friction than the torque spec expects, and your measurement will be off.

In critical locations, like connecting rod bolts, the size and weight of the bolts are critical, so you can't use bolts that are too big. But the loads are extreme, you need every bit of strength you can get. Those bolts are torqued by actually measuring the stretch with a micrometer.

There's a ton more to this, but you get the idea. You'll find tons of people on the Internet saying all they need is their calibrated wrist. You won't find them working on airplanes or race cars.

The above is all solid engineering fact. This is an opinion. The often seen clicker torque wrench is fast and easy to use. But it can also easily go out of calibration, and you'll never know. If you forget to zero it every time you put it away, the loss can happen fast. And that's so easy to do. Nobody, except those airplane and race car guys, checks the calibration. Ever.

So I use nothing but dial types, with a max torque pointer for where you can't see the dial. They're far more reliable. Also reliable are the electronic strain gauge versions, but they're big bucks.
 

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Excellent explanation, Tryker.

There are bolts where it is not that important on your bike, and others where it's very important. Additionally, you'd be surprised how easily you can over torque your bold just relying on your arm and hand as a judge.

One will think you're not capable of breaking or striping a bolt, only to find out that you can. Years ago I stripped out a oil pan bolt, and once also broke off a rotor stud putting a wheel back on my car. I would had never thought I could apply that much force...

Had a friend in the car repair business then educate me on using a torque wrench and putting about 100 ft-lbs on each bolt of a car's bolts on the wheel. I did that and couldn't believe how little force it took to reach 100 ft-lbs.

15-20 ft-lbs for many of the bolts on a bike?....like the oil pan? I found out that is really very little force on the wrench...

I think many people would under estimate how much force they are putting on a bolt if they had to guess. I don't think you have to use a torque wrench all the time, but on critical bolts, you should. And, you should use that wrench to find out what 25 lbs feels like, what does 50 feel like...and what 80 feels like...
 
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Does torquing really make a difference and if it does, HOW? It seems to me that getting the bolt tight would be good enough. I'm sure you guys can explain to me why I need to go buy a torque wrench. As you can tell Fred's videos are in my library and one day I might get enough nerve to do something besides change the windshield. Thanks
Generally torque wrenches are a good thing to have. This most important for those who have limited mechanical experience. Veteran mechanics in general develop a feel for what is tight enough and know when to stop.
In general the average Joe has the idea that things can never be to tight so what you end up with is a machine with stripped bolts, cracked plastic and other bolts so tight a fire wrench is required to loosen them.
It is a real good idea to use an inch pound wrench on those small fasteners (10mm) and the ones holding plastic should be snug not tight.
Once you start using an inch pound wrench you really find out how little force it takes to tighten these to recommended settings

Some things should never be torqued nor tight, like spacerless bearings. On the wing this would be steering head bearings on cars and trailers it would be wheel bearings as torque or tightening bearing will destroy them in time. General rule is finger tight only for these never tight.

The type of torque wrench does not really matter as they all do the same thing. Some people like the click wrenches other the pointer. I have several pointers in foot pound and inch pound and prefer them as I think they provide a more accurate feel. The key is to buy one and use it and in time you will surprised as to how close you will tighten bolts just by feel.

For wheel bolts you can use an air wrench with a torque extension. These extensions automatically limit the torque to a specific value so the bolts are just right without the need for a torque wrench.

This was a good question to ask and the responses have been very informative. :yes1:
 

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When working on the bike, I use a torque wrench on almost everything.
 

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As Tryker said, it's based on what the bolt or nut is used on and how much load is required to keep the bolt from working loose.

If the manufacturer said to just tighten the bolt, a 10 year old girl may think it's tight enough when it's not much more than finger tight to you and I.

It is a standard that is measurable against a known force.

If you use a torque wrench then you know that you are safe and can ride confident that the bike will not rattle apart or that the bolts are not too tight that vibration may lead to excess force on the bolts where it may break.

The hobby is risky enough, why throw chance into the mix to add to that risk?
 

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If wing7 needs us to convince him to get a torque wrench then maybe he doesn't have the skill level necessary to turn wrenches.
 

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If wing7 needs us to convince him to get a torque wrench then maybe he doesn't have the skill level necessary to turn wrenches.
We all had to start somewhere. Give me a guy who asks the question, over the calibrated wrist folks, who say you can ignore manufacturers torque specs. Any day.
 

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Discussion Starter #10
We all had to start somewhere. Give me a guy who asks the question, over the calibrated wrist folks, who say you can ignore manufacturers torque specs. Any day.
Didn't have a clue that a basic question would elicit a putdown, but wing renter could be right. Never saw or really understood the need to torque an oil pan bolt but I can understand now that it might be a good idea and certainly wouldn't hurt to do so.

Then of course I have read threads on calibration issues. Just wonder if they are like air guages and almost every wrench gives a different reading. Thanks for your replies. I may still not have the skill to turn wrenches but I do have an understanding that I didn't before.

I am still not going to be afraid to ask a question that will help me just because I'm afraid someone will call me stupid and I will think more on the few bolts that don't take skill to turn. Thanks again guys
 
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Wing7 you asked a good question and I think you have recieve plenty of good info in return.
Good luck with your wrenching
 

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Didn't have a clue that a basic question would elicit a putdown, but wing renter could be right. Never saw or really understood the need to torque an oil pan bolt but I can understand now that it might be a good idea and certainly wouldn't hurt to do so.

Then of course I have read threads on calibration issues. Just wonder if they are like air guages and almost every wrench gives a different reading. Thanks for your replies. I may still not have the skill to turn wrenches but I do have an understanding that I didn't before.

I am still not going to be afraid to ask a question that will help me just because I'm afraid someone will call me stupid and I will think more on the few bolts that don't take skill to turn. Thanks again guys
You asked a very good question, and with just one major exception received some good answers. Don't let answers like Wing Renter's bother you. The vast majority of the people here are trying to help, but there are a few who just seem to get their jollies trying to put others down.

Ignore them, and they'll go away.

Glen
 

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Didn't have a clue that a basic question would elicit a putdown, but wing renter could be right. Never saw or really understood the need to torque an oil pan bolt but I can understand now that it might be a good idea and certainly wouldn't hurt to do so.

Then of course I have read threads on calibration issues. Just wonder if they are like air guages and almost every wrench gives a different reading. Thanks for your replies. I may still not have the skill to turn wrenches but I do have an understanding that I didn't before.

I am still not going to be afraid to ask a question that will help me just because I'm afraid someone will call me stupid and I will think more on the few bolts that don't take skill to turn. Thanks again guys
I work with calibrated torque wrenches everyday as part of my job. Can your everyday sears craftsman torque wrench go out of cal? Yes, but under normal duty and with proper use and care of the tool, it will last many years. We have used various brands of torque wrenches from clicker type, to pointers, to our snap-on strain gage type. In my years working here I have seen these tools severely abused and remarkably they have all stayed pretty much spot on as far as cal is concerned. I have not seen too much variance either from one wrench to another although the pointers are really the least accurate and they are not over 3 or 4% off full scale. Buy as good a torque wrench as you can afford and relax..
I have been working on cars and such since 1976. I do have a great feel for torque, I could probably get within 10% of any given torque value from 5Nm to 175 Lbft. Is that good enough? Hardly.. I use my torque wrenches at every opportunity.

Joe
 

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wing7, I will give you one slightly different bit of good advice. you don't need or sometimes WANT to use a torque wrench on everything. Why? Because almost all torque values are set for use at the factory where everything is new and properly lubed if necessary. Months or years or decades after the fact, metal has aged, parts deteriorate, and sometimes a torque value isn't good anymore, and some common sense must prevail. I am talking mostly about non-critical and small parts. Critical parts would include suspension bolts, Rod/main bearing cap bolts, head bolts, mainly big stuff that is important that it be right. Non-critical bolts or nuts would be things like valve cover bolts, nuts/bolts on decorative caps, or small parts.

Example: I have a car where the valve cover bolts are the type that bottom out to prevent a gasket from being over tightened and squished too thin. These are also very small bolts that go into soft aluminum. There is a published torque value, and the first time I worked on my car and had the valve cover off, I used my new and calibrated inch pound torque wrench, set to the factory setting and stripped out the first one I tried. Then I decided if the bolt bottoms, I can hit that point, give it one tiny tug with a small wrench, and I am good to go. There are many places where even a very good torque wrench just isn't needed and may even do harm.

You will develop a good sense for what is right after working on stuff over time, but remember when going into soft metal with small bolts, take it easy, and sometimes, there is no need for using that torque wrench.

Oh, and keep asking questions. The put-downs that some people love to use are not what a normal person on this list will do. Ignore them and maybe they will go away!:thumbup:
 

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Discussion Starter #15
Thanks very much for all the replies. I could do a lot more to the HD but the GW is a very different animal for me. The Harley was a lot simpler to work on. Yeah I know why.

I've seen a lot of threads stating that the mechanic or dealership that worked on their bike screwed something up and they didn't find out until later. Some don't trust anyone to work on their bike. I'm just trying to get to a point where I can trust myself and it won't cost big bucks to fix something I screwed up to begin with.

Thanks Again
 

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Another reason a torque wrench is required in some instances is to insure all the bolts of a unit are tightened equally. Example: head bolts, main and rod bearing caps.
 

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Didn't have a clue that a basic question would elicit a putdown, but wing renter could be right. Never saw or really understood the need to torque an oil pan bolt but I can understand now that it might be a good idea and certainly wouldn't hurt to do so.

Then of course I have read threads on calibration issues. Just wonder if they are like air guages and almost every wrench gives a different reading. Thanks for your replies. I may still not have the skill to turn wrenches but I do have an understanding that I didn't before.

I am still not going to be afraid to ask a question that will help me just because I'm afraid someone will call me stupid and I will think more on the few bolts that don't take skill to turn. Thanks again guys
Sorry, but almost any thread on this board seems to draw out the trolls anymore. You did ask a legitimate and relevant question. Don't let the Morons discourage you. BTW, I am a mechanic and I can tell you that 99 percent of the time a torque wrench will keep you out of trouble. Good luck.
 

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Good question. Often tighten by feel is adequate. Most of the earlier replies pointed out when it is more critical to use torque values. The manufacturer covers themselves from liability by specifying torques for everything. That also benefits wrenchers who like to be careful.
 

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Don't need a torque wrench ???????????

Probably don't need micrometers either ??????????

"Torque wrenches. When it absolutely, positively, has to be right."
 

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Don't need a torque wrench ???????????

Probably don't need micrometers either ??????????

"Torque wrenches. When it absolutely, positively, has to be right."
I say it differently. "Torque wrench. When you'd like it to be right."

I'm truly baffled at the people who think that not using a manufacturers torque specification is somehow a mark of a good mechanic. My racing background revolts at the thought. If any race car or airplane mechanic, however experienced, with however great feel, fed that line to their boss, they'd be fired so fast it would make your head spin. I agree some supposedly professional car and motorcycle mechanics do it, and many of us have suffered the consequences, whether small or large.

Anticipating two arguments. If the threads aren't in good enough condition to be torqued, I don't think they're in good enough condition to be used for something with a manufacturer specified torque. That bolt deserves a flotation test. :) When you're working on your vehicle, the fact that you can get away with something is not a good reason to do it that way. It's true that consumer vehicles are overdesigned, and not getting the proper clamping force from a bolt can be still within the requirements. But why would you want that?
 
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