Torque Wrenches
 

Who has them? Do you wish you didn't buy them? I'm trying to justify buying two plus a bit set. Right now I see it as an investment in myself because I will prevent myself from breaking something in the future which would then cost me money. Example: carbon handlebars: $170. Torque wrenches and bit set: $70. Total investment: $240. Cost of replacement handlebars if I over torque the stem: $170. Total investment $340. Pretty easy to justify it no?

Well,

depending on what you want to buy, I would recommend purchasing one where you can set the tension to alert you (versus the Park Tool version I have, which merely provides a meter).

many ppl, including me, will recommend the latter.

Seriously Karl, what do you really need?

Well, I didn't always own a torque wrench. I rushed to buy one after I broke a seat post clamp. I thanked my lucky stars that the bike seat post clamp/seat tube interface on my carbon bike was thoughtfully designed, in that the cheaper seat post clamp broke, instead of cracking my seat tube.

So for me, it was the smart thing to do. Especially since I am slouching towards independence from the bike shops regarding maintenance.

When people who are owning carbon frames for the first time ask me for advice, I always say get a torque wrench and a Deda Dog Fang (or something similar).

Good luck.

It seems another option would be to use a power drill and use the same torque setting. Won't work anywhere a 360 degree access is not possible. Is there a known setting for power drill torques? If not, someone with the torque wrench and a power drill could post the approximate calibrations.

I have the Park Tools that alerts you to the set torque - I beleive in going over all the bolts periodically and making sure they have not loosened. I have the Park Tools bit set also.

Huh?

There have been heated debates about the need for a torque wrench. I have one but don't use it very often. If you have some sense of feel, use carbon assembly paste, and tighten things such as stems with enough force to make sure it holds but don't go gorilla on it, you're very unlikely to break anything.

People will fire back and say that there's no way that anyone can precisely feel what 6nm is, and they're right. However when tightening things on a bike, you don't have to hit a precise torque spec, you just have to tighten it tight enough to hold, without exceeding the maximum torque, and that is not hard to do.

All that said, if you have no feel for how tight things should be, and want some piece of mind, buy a torque wrench.

I think I have a feel for 6nm but my owners manual calls for 6.8nm on most bolts and I have this thing about correct torque. I even use a larger torque wrench on the lug nuts on my car - to make sure I don't warp the rotors. Proper torque is more than just not having something come loose.

I have a few, being an LBS wrench. I usually recommend Park Tool's beam-type for home users, not their clickers. Beam is cheap. Beam is tough. Beam gives you continuous readout so you can see what's happening. Beam doesn't go out of calibration if/when you forget to zero the wrench after using it, because it's self-zeroing. And beam doesn't require setting and unsetting, which is probably less of an issue when you aren't using it all day.

If you feel beam is not chic enough, get some Precision Instruments dial-types, wooooo dials! ;) They share most of the benefits of beam, other than arguably toughness.

http://i240.photobucket.com/albums/f...n/IMG_0046.jpg

They're not a cure-all, you'll still need to go in rotation on multi-bolt clamps and make sure the clamp's coming together as designed. And I've seen stuff break anyway, bikes simply are not in the same engineering league as aircraft or BMWs.

Not in the context of tightening a stem, handlebar clamp, seatpost etc.

The "proper torque" for those is enough torque that the part doesn't slip and below the amount that will break the bolt or crush the part.

There's no advantage to tightening a stem bolt to 6.8nm if 5nm holds it firm, particularly with TACX assembly paste.

I can't think of a single situation on a bike, where having the torque a bit below the maximum specified torque is going to cause any harm whatsoever, as long as it's tight enough to hold the part firmly.

In fact when I first got my torque wrench I broke a bolt tightening a stem bolt up to the torque spec on the stem. I would have been far better off quitting tightening the bolt when the stem was snug, instead of trying to hit a specific torque spec.

What may have happened there is you were trying to tighten one bolt at a time, you have to tighten all bolt evenly. Also don't assume all stems have the same specs.

I have both beam torque wrenches and a click torque wrench. I used them all on a regular basis when I work on my bikes and cars (you don't want to overtighten a bolt or a spark plug on an aluminum head engine).

If you practice using them, the beam and click wrenches are equally accurate.

Many companies (including Trek and Reynolds) sell a small torque wrench that is permanently set at 5 Nm--this is the torque value for many bike bolts that need adjustment on a regular basis.

Hope this helps.

For the small stuff like you want it for I like and use the most is a Wiha 28554 TorqueVario-S Handle, Newton Meter Scale 2.0- 8.0Nm not cheap but worth every penny, you also want to get these 2 adapters for a full range of uses Wiha 28582 Square Drive Adapter For 1/4-Inch Sockets and Wiha 28581 Bit Holder Adapter For 1/4-Inch Drive Bits adapters can be found for only $8 each.

Wiha 28554 TorqueVario-S Handle, Newton Meter Scale 2.0- 8.0Nm
http://www.jtgraphics.net/images/bik...wiha_28554.jpg

Get at least the Wiha 28581 Bit Holder Adapter For 1/4-Inch Drive Bits and you can use any 1/4" bits with it.
http://www.jtgraphics.net/images/bik...it_adapter.jpg

and if you want to be able to use sockets also get the Wiha 28582 Square Drive Adapter For 1/4-Inch Sockets
http://www.jtgraphics.net/images/bik...et_adapter.jpg

Proper torque also provides tension on the threads preventing loosening.

Nope. I was tightening the 2 bolts, alternating a little bit at a time. The crap bolt simply gave way before the torque spec on the stem was reached.

The bolt was below the torque spec, but well beyond the point that there was any reason to tighten it, other than to "comply" with the torque spec.

My point is with things like bicycle stems, if they're tight enough to hold and not slip, there is no reason to tighten them further, just to meet a moagic number on the stem.

Torque specs on 4mm bolts are pure BS.

I have torque wrenches but I rarely use them. With a good sense of what "tight enough" entails for various bolts, they aren't usually necessary. That comes with experience and if you're ham-handed, you might still need the security of a torque wrench.

When I do use a torque wrench, I generally find the torque spec is higher than what I'd use without one.

You do realize that the 6.8nm for a M5 (4mm allen bolt) is the top end of a range. It doesn't mean you have to tighten it to 6.8nm.

It means you shouldn't exceed 6.8nm. so if you're fastiduous about tightening them to 6.8nm, and your torque wrench is off a bit, you may actually be exceeding the maximum torque spec.

See: http://www.bike-manual.com/brands/bo...ut_torque.html

Fun....

Can you work on a bike today without a torque wrench? Yes. Would I recommend one? Yes. Are they "worth the investment"? ....don't even know how to answer that. It's like saying you want to go on the internet and are wondering if the computer is worth the investment. Just doesn't seem to make sense to me.

I have been wrenching on cars, motorcycles, and bikes for a long time. Never used a torque wrench on a bike and never had a problem because of it. But as has been said already if you are not confident in your "feel" of how tight bolts should be then get a torque wrench. Also as "merlinextraligh" has pointed out the recommended torques may be more than is required for the job. Bicycle bolts are not under heavy cyclic loadings like a connecting rod bolt and as such fatigue failures from under torquing are not a problem.

I need '06-'08 zipp tubulars ken! I bought the parktool TW-1 last night, a bit set on amazon and am going to sears today for their 0-100nm wrench.

Remember, some values are for dry threads and some are for greased threads, some values are max torque some are preferred torque. After realizing all of that, I stopped using a torque wrench on my bike. I use finger tight, a little tight, regular tight, BB tight, and cassette ring tight. It works pretty well for me.

This is what happens when you blindly use a torque wrench:

http://hphotos-snc3.fbcdn.net/hs566...._3549529_n.jpg

Notice how the bottom bolt is tightened further than the top? Whoever assembled this tightened the bottom bolt first, nearly to spec, then tightened the top. The top bolt hit spec much faster than the bottom bolt because the threads weren't aligned due to the lower bolt being over tightened.

The integrity of a bolted joint relies on all the bolts being evenly tensioned at all times so the circumferential pressure on the clamped part is evenly applied. Learn how to tighten bolted assemblies properly if you are going to work on your own bike. If you feel like you aren't able to tighten bolts by feel, or you merely don't want to learn, take it to a shop. If you can't do it by feel, you can't do it by torque wrench either.