Plainsman

I've had this bike in pieces for months, and have finally gotten around to putting it together. This is my first build. I'm an instruction reader, and as I get ready to add various components I notice that practically every nut and bolt says how many in-lb or newtons to tighten them. I've got the Zinn book and I see there is an appendix in the end that lists them.

I'm not a mechanic, but I would like to understand how a road bike really works (thus this project). Do I need a torque wrench(es), and if so, could anyone recommend a good AND inexpensive one. Oh wait, those two usually don't go together Okay, a decent one. I guess I would need a bunch of different sockets too?

(My LBS already did the headset - knew I didn't want to buy one of those tools, and I have a buddy with BB tools, so I'm good there)

MattP.

No, you don't need one.

sivat

If you want to do it right, a torque wrench is nice to have. Its the one thing that I disagree with sheldon brown on, as he says you don't need one. Even an experienced mechanic can't guage torque perfectly. If nothing else, use one until you get the hang of what a newton-meter feels like (or lb-in/lb-ft if thats your thing). Learning how to properly torque a fastener will mean less chance of bolts loosening, less chance of stripping a bolt, and in the case of square taper bb's, less chance of damaging the arms and bottoming out the bolts. Since perfect accuracy isn't crucial, one of the beam torque wrenches will work fine. I like craftsman:

here.
24.99 online

Plainsman

Thanks!

Feltup

Its a bike, not a car engine. You do not need a torque wrench. How do I know, I have a torque wrench and never use it.

Bobby Lex

+1.

Back in the day bikes and bike parts were generally overbuilt and it was hard to truly over-torque things. As the trend moved to shaving grams off parts and to the use of exotic materials that are more delicate and expensive the benefits of using a torque-wrench increase.

Over-torquing carbon parts (seatpost binders, brifter clamps, stem bolts, etc.) can not only be expensive mistakes, they can lead to catastrophic failures which can result in serious injury.

Do you need a torque-wrench to work on your 35 lb. 1970's era Schwinn Varsity? Probably not.

Do you need a torque-wrench to work on your 16 lb. Cervelo Soloist? You betcha.

Bob

HillRider

I agree with the desirability of owning and using torque wrenches, particularly for the new bike mechanic. An experienced mechanic with years of working on a variety of bikes can get along fine with out one (e.g. Sheldon Brown) but the new guy has no idea how tight things should be or what the proper torque feels like. It is likely you will never get bottom bracket cups or crank fixing bolts tight enough and will probably over-tighten small bolts without one.

Bobby Lex's comment about the intolerance of very light and exotic components to improper torque is right on.

You don't need anything sophisticated like a "clicker" or electronic wrench. A plain "beam type" as shown above is fine for any bike work since you can always see the scale.

MudPie

I agree completely with Hillrider. I'm also an instruction reader and feel you can't go wrong if you follow them. I use a torque wrench whenever I can. A common post on here is loose crank arms, which is remedied by proper torque on the crank arm bolts (around 30 to 35 ft-lb). I've seen some apply "gorilla" torque which is unnecessary, can damage or make disassembly that much harder.

You'll need sockets and hex-bit sockets (for Allen screws). You won't need many, but they're cheaper if you buy them in a set. I suggest higher quality tools, like Craftsman. They'll last you a lifetime. I've used poor quality tools, with loose tolerances that damaged fasteners.

vw addict

I like how people at my shop refuse to use the torque wrench on say for example Truvative crankarms. Then the customer buys the bike, comes back in with it a week or so later with the bike in on hand, and the crank that fell off in the other. Then I have to deal with calling Truvative all the time for replacements beause the crank/BB interface is now all screwed up. So, no, you don't need to use one.

Feltup

I have never in all my years of riding had a part come off or fail (yes I have carbon parts)due to under or over tightening. I guess some people just have a feel for those things. If your new I can understand but it is not a need to have to ride item. If some one working at a bike shop doesn't have enough experience to know how tight crank arms should be they need to find another job.

mcoomer

Torque wrenches can be had relatively cheaply so I would get one. Do you have to have one? No. Is it nice to have one? Very!

Plainsman

Thanks a lot all. I've found this extremely helpful. I've decided that for around $30, I might as well play it safe and buy one. The bike I'm putting together is not expensive by most forum standards I guess, but to me money is money and I don't want to ruin anything. I am brand new to "wrenching" (right term?), and not really mechanical, so it sounds like something that would at least give me some confidence and take away some of the fear of breaking something. (I have a CF/ZR9000 Trek my wife gave me a year or two ago, but I never want to tinker with it for fear of doing more harm than good)

Hopefully this build will help me "build" the confidence and knowledge I'm looking for.

One more torque wrench question. Is it possible to buy one wrench, or do I need two - one for the small stuff and one for the big stuff? (A friend is already coming over with his tools to help me through the BB and Crankset)

Thanks!

mechBgon

I have two, a Snap-On TQFR-series for bigger stuff and a cheapie Craftsman twist-handle clicker-type for the small stuff. Do I use them much? No. I'd use them where they matter, since I have the option... clamping a stem to a carbon steer tube, sure. Clamping a carbon bar into a stem, sure. But I'm not going to fuss with torqueing my rear derailleur to the frame's rear-derailleur hanger at precisely 70-85 inch-pounds If you're a newbie and don't know how stuff goes together, by all means do follow the instructions, and torque your rear derailleur to your frame with your torque wrench, etc.

When fastening stuff that has multiple clamping bolts, such as a four-bolt faceplate on a stem or a two-bolt stem clamp to the steer tube, do try to do it evenly in rotation, stagewise, don't just crank the bolts to precisely 120 in-lbs. one at a time with your torque wrench and call it done. Also, lube the threads and other contact surfaces on stuff appropriately, so you're not pouring torque into overcoming the friction of bare metal-to-metal contact.

Park Tool has a small-sized beam torque wrench for little fasteners if you want a small one. https://www.performancebike.com/shop/....cfm?SKU=11387

Plainsman

So for example, if I'm putting on a four bolt face plate for a stem, start at the upper left, and work clockwise, taking each to, say, a third of the required torque, for 3 rotations (totalling 12 different bolt tightenings? Is this correct? Great tips, I really appreciate them.

mechBgon

If the stem manufacturer sends instructions, then go along with theirs. If they don't, then as a best practice, you might want to put it together and begin snugging the bolts gently by hand while making sure the faceplate is going on evenly (assuming it's designed to, unlike my Salsa SUL-type stem). Once you got to where it was getting a bit of clamping pressure and was obviously coming together evenly, then you could bust out the torque wrench, set it for 1/4 of the final torque spec, and begin giving the bolts 1/4 turn at a time, in some sort of rotation pattern, until you began getting the desired torque on all the bolts through a couple of rotations. Then raise the torque on the wrench and go through it all again at the new torque setting.

Where I'd bother with that, is delicate or sensitive parts (carbon steer tubes, carbon bars, carbon frames, ultralight stuff). If I'm slapping my old mountain bike back together after an overhaul, it being all old-school durable stuff, I'd never bother molesting my torque wrenches just for that.

roadfix

I also agree with Hillrider's comments above.
With the right feel and common sense, you really don't need a torque wrench.

Pete E

I'm new to working on bikes and I'm just putting a tool kit together...I don't have a torque wrench as yet but will probably get one or possibly two...What I don't understand is why some people are so against using them especially when they already own on...It doesn't take a noticable amount of extra time or effort to use one over an ordinary spanner or rachet..

I intend to research the various torque setting for all the different fasteners on my bike and then print it out and laminate it, and keep it with my tools...If you have more than one bike, I'd make one such chart for each bike...having the info to hand would make the whole process dead easy...

Regards,

Pete

Bobby Lex

I think it's an ego thing. "I'm such a good mechanic that I don't need no f'ing torque wrench! If you need to use a torque wrench, then you are less of a mechanic than I am."

Because, as you said, what's the harm in using one?

OTOH....

You can guesstimate the psi in your tires without using a pressure gauge.

You can guesstimate you heart rate without using a HRM.

You can guesstimate your cadence without using a cadence meter.

You can guesstimate your speed without using a computer.

You can guesstimate your spoke tension without using a tensionmeter.

And I suppose "real men" don't need these gadgets. They're just crutches. Like training wheels. Using them shows weakness. A lack of basic skills.

Yeah. That's the ticket.



Bob

InTheTrenches

WELL, while there is a torque spec for Truvativ cranks, the big problem is that even if you torque it right but do not remove the crank first, it will not bottom out against the stop. Then It will fall off a few days later. The torque is not great enough to get the crank moving, if it has not been fully torqued to begin with. Truvativ has a bulletin (or email) about this floating around (I got one). It is really a problem with their prop. power spline cranks, but also on the two piece cranks with the outboard BBs. We ended up removing and reinstalling every one that came in(after two failures and a talk with Truvativ.)

Get a torque wrench, they are not to expensive for a a decent one and any idiot can figure it how to work one. I prefer clickers because you cannot always hold it so you can read it.
Since Harris does not believe in torques spec, you might want to NOT bring them your Pinarello F4 or Scott CR1

Metaluna

The beam wrenches also have the advantage of working properly for both right- and left-handed threads, which many of the clicker types (especially the cheaper ones) do not.

sivat

One 3/8 inch drive should do it. The most you'll need to torque anything is 35lb-ft. And for the smaller bolts, it should be accurate enough to get you in a safe range.

Another tip, you should use grease, assembly lube or loctite on every thread. I use loctite on the crank bolts and grease on everything else. It will help you put the right amount of torque on the bolt and keep the bolt from loosening while riding.

poprad

I would respectfully disagree with this as an overall recommendation. It depends on what the manufacturer spec'd for that particular fastener. Many torque specs are for dry threads only, and you can actually over torque a fastener by lubing prior to assembly because the lube will reduce the friction, thereby the indicated torque. That's why engine build manuals will frequently tell you if the bolt should be torqued wet or dry. A good manual will tell you which bolts require lube/anti seize/ or loctite. I can't remember but I think my Barnett's does.

If you're really interested in this arcane stuff, there's a few really good articles out there. When you get into the science of it, torque specs are really a bad (but only) way to tell someone how tight a bolt should be. Variations in thread pitch and tolerance from one fastener to another can make the torque readings vary significantly for a given setup, as can differences in the finish of the threads (chrome/machined/coated). Having said that, the aerospace industry uses torque specs on almost every significant bolt, and they fall out of the sky if they're torqued wrong.

One note, too much clamping force on critical components could cause micro cracks (invisible to the eye) that when stressed (bunnyhopping a log, etc...) could result in critical failure. In a seatpost for instance this could result in serious injury, so I would suggest really paying attention to manufacturer provided torque specs for critical areas. They don't pay those engineers to dream that stuff up for nothing, their lawyers make them do it so when the LBS can't testify they torqued it right, the LBS takes the "fall" not the manufacturer. This applies to you, the owner, because if you can say you used a torque wrench and then the fork (handlebar, seatbinder, other) failed in normal use causing you grevious injury, the maker can't say it was your fault for poor installation. Sounds like an overly complicated and redundant thing to do...until you're the guy missing part of his jaw...or the LBS being sued by the guy missing his jaw.

And I like torque wrenches..my Pedro's is a nice piece of kit.

HillRider

A 3/8" drive torque wrench with a 50-ft-pound max range is really adequate. A 1/4" drive torque wrench would be more precise for the smaller bolts but isn't essential.

Metaluna

Also it's hard to find metric hex bits with 1/4" drive so you'll probably have to use an adapter which is a bit (no pun intended) of a pain. The adapter that came with my Park fits loosely and tends to fall off, for example. I finally bought a socket set made by SK Tools but it was expensive. Pedro's markets a set for much less but I couldn't find it in stock anywhere.

mechBgon

Proto makes nice metric hex bits in 1/4". Loctite the bit-retaining setscrews if you get some Protos.