Check the torque on your bolts regularly!

[-Ralph-]

Was doing 80mph on this this morning. There was one hell of a head wind, and this bike weaves with a headwind anyway, but it was like minnow in a panic this morning. The steering didn't feel right, the bike was needing a turn of the bars not just a countersteer, and braking was a bit vague. Then I felt a clunk at the front and thought, WTF was that? And stopped for a inspection!

This is 2000 miles since the front wheel was off at a tyre fitter, so check em regularly, not just at service time folks! This could have killed me!

http://i227.photobucket.com/albums/dd82/colinbal4/SNC00022-1.jpg

[fastdruid]

Hmmm, I blame the tyre fitter. I bet he just nipped them up rather than torqued them.

No bolts should ever work loose if tightened properly.

Druid

[barwel1992]

^ unless over stretched

but yes as above good bolts should never come lose when properly torqued

[fastdruid]

If over stretched they've not been tightened properly. :-)
(or are single use and not replaced when they should be eg Honda brake caliper mounting bolts).

Druid

[barwel1992]

If over stretched they've not been tightened properly. :-)
(or are single use and not replaced when they should be eg Honda brake caliper mounting bolts).

Druid

lol ok ok maybe i should have said that lol bit vague i suppose :p

some garages like to use the industry standard torque setting on stuff EG FT (****** tight)

so when some one uses the correct torque they are lose as your gran :smt037

[Specialone]

I was with ralph today in a field a couple of km down a green lane, scary really when you think what couldve happened.
We were riding on Tarmac, mud, bumps etc, that coming off at 70mph doesn't bare thinking about.
Least you spotted it mate :)

[Dicky Ticker]

possibly not so much on motorbikes but trucks require wheel nut checks frequently and over tightening is just as bad as loose as it tends to stretch the wheel bolt and it will snap off.
I know certain people on here do not agree with me regarding using torque settings as defined by the manufacturers but they have there reasons for these settings as is becoming apparent by the examples that are being quoted

[Teejayexc]

Now this is scary.....




I was with ralph today in a field a couple of km down a green lane, scary really when you think what could've happened.



Each to their own :smt016

[-Ralph-]

Each to their own :smt016

:smt098

[Specialone]

Now this is scary.....




Each to their own :smt016

:smt098

I 2nd that motion :)

[-Ralph-]

Is this more likely to happen on an off-road bike? I'm not Marc Coma or Cyril Despres (in fact I'd propbably struggle in an amateur enduro event ;-) ), but that said I don't ride along looking at my front wheel either, and I often tackle rough surfaces by opening the throttle. Specialone will tell you that I don't crawl along. I expect the forks and 21" spoked front wheel to do what they were designed for, I don't give them an easy time. At an estimate 500-750 miles of that 2000 was on rough surfaces, that is the bikes raison d' etre.

[Specialone]

Your forks etc are obviously gonna take more of a pounding but cope with that pounding better than a road bike.
Just a case of poor tyre fitting that's all IMO.

[mikerj]

I know certain people on here do not agree with me regarding using torque settings as defined by the manufacturers but they have there reasons for these settings as is becoming apparent by the examples that are being quoted


The examples quoted here aren't caused by torquing a fastener up slightly out of the manufacturers spec, it's caused idiots either not tightening a fastener at all, or hugely over tightening it. It's perfectly possible to torque most standard fasteners close enough to the required value without using a torque wrench if you have a reasonable level of skill and experience. If you don't then I agree a torque wrench should be used, and it should always be used on really critical fasteners e.g. head bolts.

[Dicky Ticker]

I sorry I disagree yet again,crushed speedo drive on a front spindle probably cause by overtightening,secondly front spindle comming undone due to undertightening.
Both scenarios where +/- 5lbs could be enought to cause this. Industry standard would be about 45lbs so 40-50lbs by guestimate on a large nut or bolt head like a spindle is not a lot of pressure and for the DIY mechanic using a fair sized socket wrench or spanner very hard to get within the peramiters,especially if it has corrosion or burred threads.
We are all entitled to our own opinions

[-Ralph-]

It's perfectly possible to torque most standard fasteners close enough to the required value without using a torque wrench if you have a reasonable level of skill and experience. If you don't then I agree a torque wrench should be used

I use a torque wrench on everything, and I always use exactly the spec the book says. This is because I believe I don't have the experience to get it right by hand, or to know if the value in the book should really be less or more.

Maybe if I owned a smaller torque wrench of similar length to the ratchets in my socket set and smaller range, I would perhaps learn what a certain torque value feels like over time, but I don't, my torque wrench is about 450mm long and has an operating range of 28 to 210nm. Most nuts need very little effort when you use something that long, especially if it only needs 30nm, and you don't learn how much pressure you would need to apply with a normal ratchet.

I wanted a wrench that size for the rear wheel spindle and for the wheel nuts on the car. Maybe a smaller wrench with an operating range up to 60 or 80mn for those kind of bolts can be on my birthday list.

[dirtydog]

I wanted a wrench that size for the rear wheel spindle and for the wheel nuts on the car. Maybe a smaller wrench with an operating range up to 60 or 80mn for those kind of bolts can be on my birthday list.

I've got 2 torque wrenches a long one like yours 450mm upto about 200nm and a 300mm that I bought from halfords a few years ago has a range of 8-62nm. I tend to use the shorter one the most. Plus it's a 3/8 inch drive so fits pretty much all my sockets.

[mikerj]

I sorry I disagree yet again,crushed speedo drive on a front spindle probably cause by overtightening,


If this is really the case (and I highly doubt it) the spindle would have had to be been torqued up to a ridiculous figure to crush the speedo drive. +5 lbft simply wouldn't have done this.


secondly front spindle comming undone due to undertightening.


Again. -5 ftlbs would NOT have caused this, you are showing a grave lack of experience if you truly believe this.

I've had bikes for the last 30+ years and I have not ever had a bolt loosen or snapped a bolt due to over or under tightening. Perhaps I am simply "lucky", but the evidence tends to suggest that experience and a good level of mechanical sympathy is vastly superior to the blind following of torque figures.

[mikerj]

I use a torque wrench on everything, and I always use exactly the spec the book says. This is because I believe I don't have the experience to get it right by hand, or to know if the value in the book should really be less or more.

Which is fine, and you will build the experience and skill to know what an appropriate torque value feels like for most fasteners. However, it's not unknown for an incorrect torque figure, or maybe even the wrong units to be printed in a manual, so even with use of a torque wrench it's good to have a feel of whether the value is in the right ball park.

[Dicky Ticker]

Mikerj,If you have never had a bolt strip or break in 30+ years of fitting you are a better man than me.I have spent 40+ years working on all sorts of engines and know that corrosion,heat or stretching can make a bolt susceptible to breaking and steel bolts into aluminium are the worst when you do not know what has been done previously.
Yes,I will fit something and do it up without a torque wrench and be pretty near the setting but for the sake of checking it I was taught to err on the side of caution and do a torque check-----a spindle is a single nut so about 10 seconds.
Why do tyre fitters torque check wheel nuts as does a good mechanic on a service.They were probably all tight when initially put on but can slacken off Reason for the disclaimer when you have new tyres fitted.
The number of clutches,bearing caps or heads I have seen knackered due to not being pulled down or fitted properly beggars belief.
There is a lot of difference between somebody who does it for a living and somebody who does it as a DIY mechanic and if they don't have the professional skills they are less likely to damage something if they are doing it by the book and use the torque settings.Most of the people on here have a limited mechanical aptitude and it is they that I am trying to help not teach a time served mechanic how to do his job


It maybe better if I keep my advice to myself in future and just let people get on with it in their own ways,in the end dilligaf.

[timwilky]

DT knows my pedigree as I know his. I respect his view and mostly agree.

I hope I still retain a sympathy with fasteners. I always use a torque wrench where appropriate. However, I do not use it blindly. I combine it with feel, if I am not happy with the feel of a fastener before it has reach the appropriate torque, I back it off and investigate why. I would rather throw a nut/bolt in the bin than risk it stripping or fracturing.

The problem with tightening used fasteners is you never know what the previous spanner wielder has done. You would hope that when tightened the fastener was still within the elastic region of a stress/strain relationship as once beyond the yield point deformation is permanent.

Secondly, there is an issue with lubricated threads, the derived clamping force will be higher with a lubricated thread at a set torque and you could end up with deformation of whatever you were bolting up.

[kwak zzr]

personaly i dont torque bolts anymore anyhow, i used to until my torque wrench snapped a bolt that apparenty wasnt tight enough according to the wrench reading? ? ive never had any problems with a bolt ive tightened but when the bike has had work done not by me i do always check bolts more so wheel spindles.

[daved407]

Having read both threads I would thread lock the studs into the fork leg and tighten the nuts dry, by feel or using a torque wrench.

What I have noticed is the blind faith some but not all people put into a torque wrench. I have worked with a large firm that had its torque wrenches calibrated regularly. Those outside the tolerance were thrown or recalibrated if possible. Yet they still fail between inspection periods (it happened to me on a cam bolt) and It has also happened where a new unused torque wrench failed its cal. I wonder how many private owners have ever tested their wrench out or checked them on a guage. Basically if it feels too tight with a 450mm wrench, torque or otherwise be careful. Steel bolt into Ally, there can only be one winner.

[mikerj]

What I have noticed is the blind faith some but not all people put into a torque wrench.

I totally agree. Using a torque wrench with no idea what the correct torque for a particular size of fastener and material should "feel" like is a disaster waiting to happen.

[-Ralph-]

I totally agree. Using a torque wrench with no idea what the correct torque for a particular size of fastener and material should "feel" like is a disaster waiting to happen.

What do you suggest a newbie mechanic trying to learn what it should "feel" like should do?

[mikerj]

What do you suggest a newbie mechanic trying to learn what it should "feel" like should do?

Sadly, the only way they are going to learn is by gaining experience. Doing this under the guidance of a reasonably skilled person would minimise the number of sheared/loose fasteners.

[Dicky Ticker]

Experience isn't gained overnight and having been doing the job for over 40years I still double check with a calibrated torque wrench.The number of settings, type of materials and thread variations,plus often difficulty of access means that although I might be able to make an educated estimate as to the correct setting I still double check for MY peace of mind.
Yes torque wrenches can go out of calibration but by what extent compared with the inexperienced heaving on a spanner.

Some on here may be more proficient than others at this but my advice would be use a decent torque wrench
The bolt or nut size can be used as a rule of thumb as to the extent of tightening required but unfortunately in mass produced engines the grade of materials used in the manufacture often mean that they are lower than you would anticipate.

[yorkie_chris]

,especially if it has corrosion or burred threads.
We are all entitled to our own opinions

The corrosion or burrs would make any torque setting completely meaningless wrt the clamping force applied.

Mikerj,If you have never had a bolt strip or break in 30+ years of fitting you are a better man than me.

It maybe better if I keep my advice to myself in future and just let people get on with it in their own ways,in the end dilligaf.

I have had bolts strip, and snap when using a properly calibrated torque wrench. Flawed fastener or corrosion, it can happen.

I go with the "use your head" standard with everything I do, when riding I know best what speed to go regardless of the limit, when doing up a bolt I will decide whether it is worth just doing it up by feel or by referring to the manufacturers instructions as well as feel.

Everyone is entitled to their opinions and to voice a disagreement with anyone elses. Nowt personal, no need to get shirty about it.

[Milky Bar Kid]

The corrosion or burrs would make any torque setting completely meaningless wrt the clamping force applied.



I have had bolts strip, and snap when using a properly calibrated torque wrench. Flawed fastener or corrosion, it can happen.

I go with the "use your head" standard with everything I do, when riding I know best what speed to go regardless of the limit, when doing up a bolt I will decide whether it is worth just doing it up by feel or by referring to the manufacturers instructions as well as feel.

Everyone is entitled to their opinions and to voice a disagreement with anyone elses. Nowt personal, no need to get shirty about it.

I don't even know what a torque wrench is...:oops:.

But....it's not like you to keep the peace YC!!!

[yorkie_chris]

That is not keeping peace, that is just how it is.

A torque wrench is just like a ratchet, but you can adjust it to "click" at a certain torque (level of tightness :-P) to tighten a nut or bolt to a fairly exact level of tension.

Like when you or other coppers on here* give your opinion on legal matters based on experience, if someone says different you don't go "oh well I'll just be quiet then, I don't give a f***, #huffhuffhuffhuff#".


*Most of you, there's a certain ex one (not DT) who comes across as a patronising tw*t with little useful to add. Maybe it's a thing with the older/retired set who would rather huff and take bat and ball home rather than engage in useful and open discussion? Is it an unfortunate effect of age to be able to view things objectively rather than personally? Anyway, I digress! Torque settings....

[yorkie_chris]

The above post is off topic and taking the p*ss out of certain people. The bit below is technical and of importance. And probably worth discussing.


The corrosion or burrs would make any torque setting completely meaningless wrt the clamping force applied.

To quantify that, manufacturers give torque settings to apply a clamping pressure to a part. It's given that this is right for specific conditions. New parts, specific lubrication, a torque wrench that hasn't been used as a hammer etc.

[Stonesie]

To add to this a little, a torque wrench that is out of calibration can be a bloody dangerous thing to have in your toolbox.

In a previous job I worked for a Calibration comapny and we did a lot of torque wrenches (UKAS accredited for them) so I took my old wrench in that hadn't been used for years and it FAILED in spectacular fashon, set to 100 N:m it clicked off at something like 70, it was halfords* branded but a no-name POS that is religated to ratchet cracker-bar duties. I now have one of the medium sized Halfords wrenches and a small Norbar, which was eye-wateringly expensive.


*Halfords now sell re-branded torque wrenches that look and feel suspiciously like Norbar's, which are very, very good although I still think Britool are the most manly and reliable (you can see bits of metal moving about and they make a very strong clunk)

[tactcom7]

I'd say there are some things you torque and some things you don't, but again this 'knowing what to and what not to' use a torque wrench on only comes with experience. An RAF Chinook has a torque listing for every single nut and bolt on the aircraft. And, at first, I would get out a torque wrench whenever I worked on one. But, over the years you get to learn which needs doing and which can be done by hand and by 'feel'. On the other side, nearly every nut is either a nyloc or get's split pinned or wirelocked so you have that extra bit of confidence.
A (possibly to some) interesting fact for all you who know about torques...The big nut that holds on each rotor head (2 in total) is torqued to a figure of 5952 Lbft...

[yorkie_chris]

You wouldn't want that bugger coming undone though!

[Dicky Ticker]

What an experienced fitter does and a complete novice is what I was trying to distinguish against,and I think a novice would do less damage using a torque wrench.
I admit that many fixings can be done without torque settings but certain things are better done with them e.g. pressure fittings such as clutch,end caps and heads where a conformity is required

P.S. YC and I don't always disagree but where is his expertise is small engines I am happier with 14-16litre diesels which is a different ball park but many things are transitional

[tactcom7]

You wouldn't want that bugger coming undone though!

You'd think so wouldn't you, I remember being told by the Boeing rep that a yank went to undo the hub nut cover on top of the rotor head and found the nut handtight! apparently the gyroscopic forces of the head spinning against the shaft were the only thing holding it on.