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Discussion Starter · #1 ·
I've been wondering about this for a while but haven't ever gotten a solid answer. I know the most accurate way to check torque is to back the bolt off some then check with a torque wrench while the bolt head is actually turning.

But lets say I don't want to back the bolts off before checking for ease and just for doing a quick check to make sure the bolt isn't crazy loose - will I end up over torquing that bolt over time if I do that too many times. I'd be using a click type wrench and making sure not to turn it any after it has clicked. I can understand that this may result in allowing the bolt to remain undertorqued because you have to overcome the static friction involved with the head moving against the surface that it is against which I guess is why the best way is ti back off the bolt first, but I don't really understand why it could result in overtorqueing the bolt after checking it like this too many times. This article: Using a Torque Wrench to Properly Adjust Your Bike's Bolts - Velofix says "Avoid Checking Bolts Before Every Ride. Every time you do, you tighten them slightly. By year’s end you could end up turning a bolt one full rotation. Torque them right the first time." And I know I haev read it in another bike maintenance article talking about checking torque with torque wrenches.

This MTBr thread had some info but wasn't real sure on the consensus: Checking torque on already tightened bolts- Mtbr.com

One guy within that thread put it well as far as I understand it: "Sometimes the force required to overcome static friction is greater than the required torque on a fastener. So if you are torquing a fastener that isn't rotating, for example "checking" it, you run a good chance to undertorque because of static friction."

And for just checking torque I am fine with it possibly remaining a little undertorqued because of that static friction that has to be overcome, but if checking torque with a click type wrench could result in overtorquing bolts and crushing components then I am much more worried about doing so. Specifically, things I would check are stem bolts, seat collar / binder bolts, saddle to seatpost bolts, etc.
 

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'brifter' is f'ing stupid
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I check them all when I build the bike. I don't check them unless I do work on that particular part. If for some reason I do feel the need to confirm proper torque I'll loosen it, look to see if it needs lubrication, retorque. No reason at all to check them every ride or every week or even every month. Certain pivot fasteners on mountain bikes need checking, but if they're 'tight' I don't turn the fastener. If it's 'loose' I'll know.
 

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Discussion Starter · #3 ·
I wouldn't check them every month, maybe every 3 or 4 months at most. Basically I feel that having to loosen then retorque the bolt causes unnecessary wear to the threads if checking without loosening first is an okay way to do it, you in most instances will not actually turn the bolt and therefore not add any wear to the threads.
 

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'brifter' is f'ing stupid
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I wouldn't check them every month, maybe every 3 or 4 months at most. Basically I feel that having to loosen then retorque the bolt causes unnecessary wear to the threads if checking without loosening first is an okay way to do it, you in most instances will not actually turn the bolt and therefore not add any wear to the threads.
What's so hard about doing it the right way? So you might...slim chance, but you might put some wear on the threads...if you do, replace the fasteners. You're probably looking at a dollar or 2 to buy new ones. Do you really think that turning a screw a few times a year will damage it? :skep:
 

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But lets say I don't want to back the bolts off before checking for ease and just for doing a quick check to make sure the bolt isn't crazy loose - will I end up over torquing that bolt over time if I do that too many times.
No. If the bolt is 10Nm and you set your wrench for 10Nm, you won't exceed 10Nm.

I can understand that this may result in allowing the bolt to remain undertorqued because you have to overcome the static friction involved
Yes that's theoretically possible.

You're really over thinking this. Torqueing bolts is not an exact science. Notice that most torque specs give a range. ie Shimano Caliper mounting bolt = 8~10 Nm. Well that's a 20% difference! Also note that most torque specs aren't clear whether they're dry or lubricated. Well lubrication reduces necessary torque by 15-25%. So now we have a potential 40% difference.
If you want to torque your bolts without loosening them, go ahead. Nothing bad will happen.

This article: Using a Torque Wrench to Properly Adjust Your Bike's Bolts - Velofix says "Avoid Checking Bolts Before Every Ride. Every time you do, you tighten them slightly. By year’s end you could end up turning a bolt one full rotation.
That's just plain silly.
 

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Millions of miles have been cycled just fine without worrying about this. Move on to something else to obsess over would be my suggestion.
 

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Not bike related, more car related. Many cars use TTY bolts (Torque to Yield).. aka stretch bolts.. You cannot back them out to retorque them as they have already been stretched, and redoing everything would result in destroying the bolt.. They are one time use.. sadly.. back it out.. and you need to replace the bolts. Not sure if I have ever seen a bicycle use TTY bolts though.
 

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On one hand you aren't going to damage anything checking with a clicker so what you are doing or proposing to do doesn't hurt provided you are not exceeding specified torque during your check. On the other hand you really aren't checking anything either (in regards to the specification) other than the possibility of finding a grossly loose bolt. There is no correlation between checking the torque on a previously fastened joint and the torque that was achieved to fasten it. It took me a long time and a number of experiments running down fasteners in order to get my company and our customer to get away from the practice of using a torque wrench to audit previously fastened joints for proper torque level. Torque is measured during the fastening process only. Honestly I would not be backing bolts out and running them back down just because I was paranoid about the soundness of a fastened joint. If you are that worried use fasteners with a locking compound or better yet find something else, preferably something meaningful, to worry about.

You don't even want to know what I had to go through in order to demonstrate non-correlation (weak correlation at best) between torque and clamping force but I won that battle too.
 

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I agree with craiger-ny,, he's absolutely correct. Verifying a torque value with a beam or clicker will not damage the fastener or the component if you do not exceed the designed value. Torque values are extremely inaccurate and seldom translate to the load they are intended to achieve due to multiple issues; flank finish, thread sizes, lubricants, materials, etc., etc.. Multiple studies have shown that a properly applied load or an evenly applied load for multiple fasteners is often more important than achieving the designed value. Inshort, if it’s not loose I wouldn’t worry about,, ride and have fun!!!
 
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