Torque wrenches and bits
 

I want to invest in a torque wrench, but don’t see a single wrench that would span 2 - 60 Nm. Problem is I can find one in the lower range with 1/4 drive and a 10 - 60 Nm wrench with 3/8 drive, but I don’t want to have to buy two separate bit sets. Any advice on how to best cover whole torque span?

You cannot, accurately. That is why you see two separate wrenches.

You are unlikely to use small hex-wrench sized bits at higher torque, so buying two bit sets isn't a major issue. Many of the low-torque torque wrenches come with a bit set that corresponds to the normal-sized hex wrenches and torx bits.

The larger wrench is typically used with sockets, or bizarrely large hex bits.

They sell adapters for 1/4 to 3/8 drive changes, This set from Harbor Freight covers everything from 1/4 to 3/8 to 1/2" drives https://www.harborfreight.com/profes...-pc-57324.html
https://cimg6.ibsrv.net/gimg/bikefor...83c2c60a84.jpg

Buy a 3/8" drive bit set and the 3/8"M to 1/4"F adapter JoeTBM illustrated above to let you use the 3/8" drive bits with the low torque 1/4" drive torque wrench. Harbour Freight, Lowes, Home Depot and any decent hardware store will have it.

Learn to tighten things just enough and you won't need a torque wrench. If what you tightened later loosens or slips then tighten it a little tighter next time.

Many of the torques specified are the maximum torque they don't want you to exceed. Not the torque you must be at.

It's a bicycle.

If you have to have two or three torque wrenches then figure out which you'll use the most and get a good one. The one you use the least can be a cheapo

Or, instead of the breaking torque wrench get a beam torque wrench which are accurate and usually inexpensive. Their only negative for me is sometimes they are difficult to read from the position you have to use them from.

Almost all of my torque wrench use on bikes is a 1/4" drive, as I'm cautious on threadless stems and CF. For the bigger torque requirements, I use a $20 beam style torque wrench but I mostly use it for it's long lever and the "yeah, I'm good" on BBs.

I worked at three northern and southern California bike shops from the mid-1980s to the mid-1990s. Not one was in possession of a torque wrench.

I wouldn’t use this approach for mounting handlebars, brake levers, crank arms or several other items.

That was three to four decades ago. With the growing use of carbon, torque specs are much more critical.

I'm sure there are a lot of things that we wouldn't do the same.

I avoid carbon like it's toxic.

My bike is mostly carbon except for the wheels,handle bars and stem. No big difference from steel, aluminum or others.

Only requires some knowledge of what to do and not do just like everything else.

I've overtorqued a seatpost clamp until it broke, and a stem until it stripped. Those cost about as much to replace as a couple of inexpensive torque wrenches.

I've also undertorqued a crank a couple of times. Caught it before it damaged the crank, thank goodness -- have you priced a new crank lately!?!

As someone that has wrenched on various things all my life I see both sides of this thread.

When we first start out torque wrenches (and torque screwdrivers ) are great to have. It takes some considerable time and feel to develop the feel of the proper torque to use for day to day applications. Using the Twrench or Tdriver at this early stage is a big part of developing that general feel. But as we gain that experience a lot of times our idea of "about right" is very close to what is needed. I still use torque wrenches on some things that need matching or if they are outside my normal and more common work.

Yes there are adapters. But you REALLY want two tools rather than one. The big reason is that you want the spread of the settings for the smaller fasteners. The 60Nm wrench will technically do the small stuff around the 2N-m stuff. But the correct settings will be compressed so close together that they will be hard or just a guess to set correctly. Plus all tools have a tolerance of how accurate they are. If that is something like 3% it means % of the max reading. And % of 60 Nm is 1.2Nm. If you're trying to set a 1.5Nm screw and the tolerance is + or - 1.2 Nm? I think this shows why it's not good idea to use a higher load torque wrench for the small and lighter duty stuff. So if you're serious about the whole thing stop trying to make one tool do it all. Get both.

Interesting discussion. Buy both wrenches and buy beam types. Beam types are accurate and robust for a home shop, you need to bend or damage one of the beam components to throw them out of calibration.

Torque is a very imprecise method of loading a bolt/fastener due to all of the inputs; lubrication, machine profile, condition of the flanks, etc,,,. Several studies have shown that it is more important to torque fasteners correctly and to level or equalize the load on the fasteners than to reach the prescribed values. Studies have also shown that experienced hands can feel the right values for the fasteners and are great at equalizing the loads.

Whatever, have fun..

I don't know if you are one of them, but I've known many that do seem to think they have to tighten everything with all their might. And that does frequently result in broken bolts or stripped threads.

If one has no clue when they've tightened the thing just enough and instead continue till they've damaged something, then I'll agree that they probably need torque wrenches. However for those that don't think that every bolt or nut needs to be super tight, then a torque wrench on a bicycle isn't needed. Even for carbon stuff.

There is no shame in using a torque wrench. So any that are unsure or inexperienced at sensing when things are tight enough should use one if it helps them. This should not be something where one is wrong for using or not using them.

You miss my point; I'm not claiming to be a reformed airline baggage handler or inexperienced.

I've been told that if you just cinch the seatpost binder down to where you can't move the saddle laterally, that's tight enough. I've also done that and wondered why things felt so wonky a few miles into a bumpy ride: answer was the binder bolt wasn't tight enough. As a clyde, there's a fairly narrow range of binder bolt torques that will keep the saddle where I need it, and Oops! Too tight!

I've built up my travel bike 3-4 dozen times, and most of those were unremarkable. I'll normally get everything snug, and then go over the entire bike once more to make sure, for example, the bars don't flop down the first time I hit the brakes. (Yes, been there, done that.) Imagine putting a substantial fraction of your body weight onto a short allen wrench to snug up the crank, then make sure your stem is tight. It's pretty easy to see how that 5 Nm torque tight-enough sense gets skewed enough to strip the stem. Kind of like how it's easier to get a speeding ticket after you've been driving 4 hours on an interstate and then get off and go through a school zone!

So my intended point is that using a torque wrench is an easy and inexpensive way to prevent expensive errors caused by mis-estimating the force you're putting into a bolt, or even momentary inattention.

I think you've missed my point too.

Mostly I'm just saying that it's a personal choice whether to use one or not. And also when to use one or not. We all have varying levels of experience with a wrench and how it feels when tightening nuts or bolts in various materials or even thread pitch and such.

And I mostly object to those that say you must use or should never use a torque wrench. There are times when they are useful and that will be different for many individuals. And unless the person asking about torque wrenches says that they are a total klutz tightening things, then I'd never say they must buy a torque wrench.

For many, there is nothing wrong with doing what I suggested in my first reply to this thread. #5 I think.

We might actually share somewhat the same views, however my bias lies toward not spending for a torque wrench unless also useful for other things besides the bicycle. Where as your bias seems to be toward getting a torque wrench for use. Both perfectly good ways to go depending on things we both don't know about the OP or any other person.

As long as you agree there are potential downsides to deal with if you decide not to use the torque wrench, I can agree to that statement.

Six or seven years ago, I was right where you are now with this argument. For your sake, I hope you can avoid the slips that changed my mind!

You two both make good points. I'd suggest that they key to both sides of your discussion is the experience of the person doing the wrenching.

Describing torque values is very difficult. And as that seat bolt movement example confirms it's not always clear cut. As does using lubrication or not on the threads.

I think there's a lot of good habits and proper feel to be learned for a new mechanic. And a set of torque wrenches to suit the small and large extremes is a pretty darn handy thing to have in the early days of wrenching for anyone. The wrenches will "calibrate" the operator's feel in due time while allowing them to do safer and accurate work early on. At that point a lot of the work can be done using that "calibrated feel".

It's worth pointing out that sometimes the parts themselves help confuse the issue too. I've had seat posts and stems and other items fit with the need for a firm push. And just the first few inch ounces of torque already produced a good degree of lock. Not enough to trust. But clearly even a moderate torque was going to lock the items very safely. On the other hand I've had supposedly matching parts where I needed a good amount of torque before the parts even started to grip and the final safe degree of a lock needed near to maximum torque on the fasteners. Extremes like that certainly muddy the waters and call for a bit of reliance on experience or to seek some outside help for those not experienced enough.... Which would be where forums like this one come in....

It is the small bolts on a bicycle, e.g., stem bolts, seat post bolts, etc., which are easy to strip. Most of these bolts specify either 5 Nm or 6 Nm, so you can just buy the appropriate Topeak Nano TorqBar for <$30:

Topeak Nano TorqBar 5 with 5 Tool bits, 5nm : Sports & Outdoors (amazon.com) (5 Nm version)
Amazon.com : Topeak Nano TorqBar 6 with 5 Tool bits, 6nm : Sports & Outdoors (6 Nm version)

I have a 1/2" drive torque wrench for automotive work (mostly wheel bolts), but I don't think it would be accurate enough at the 5 Nm to 6 Nm range.

I disagree with this advice, especially with carbon parts and bits

Once I got a torque wrench it was surprising to me as to what things I was over tightening, but even more at what I was under tightening.

I like the park for small stuff 4- 6 nm https://www.parktool.com/en-us/produ...y=Torque+Tools

is use this 3/8 for bigger nm but it is not currently available....https://smile.amazon.com/Pro-Bike-To...ef_=ast_sto_dp

also have beam for higher torques and while cheaper, it is more of a pain to use without a helper

The Topeak caught my eye. But I can buy TWO fairly nice 1/4" torque wrench sets for the cost of one Torqbar. And do more with it since the fully adjustable wrenches are typically 2.2 to 22 something Nm in range from reading the specs.

And cost wise even up my way in Canada where things are more than in the US I can get a pretty nice 1/4" set for $33 to $40 depending on choice. And even the expensive ones are only up around $50. Which again supports the idea of just buy the two different sizes and consider it a life long investment. With much care at all they will last your entire life and be able to get handed down to the next generation.

I use Performance Tool M206 digital torque adapter which covers all bases for me. Its only flaw is the size that can become an issue in tight spaces, if an extender cannot be used. Cheaper adapters are available.

A 1/4" torque wrench set for < U.S. $15!?

The Nano Torqbar is tiny and fits anywhere. The seat post clamp bolt in my bike frame and the front bolt of my seat post are both very close to the seat post itself, and this is the only torque wrench that can access those two bolts.

And even if they could make one torque wrench that could perform accurately with that kind of range, it wouldn't be a good idea, business-wise. Because some doofus is bound to come along and place 60nm on a 3mm bit and... hilarity will ensue, frivolous litigation and all.