Tag Info

Hot answers tagged

10

You do this with a tool called torque (sometimes called dynamometric) wrench. Without a tool you can estimate it this way: Make yourself familiar with a weight of 1 kg Apply the force with your simple wrench 10 cm from the bolt in question This will give you 1 Nm of force. To get 5 Nm, use 5 kgs of weight or increase length to 50 cm. The math is simple: ...


10

You use a Torque Wrench. You set how much pressure, and when you tighten to that pressure, the wrench will "click" and not tighten the nut/bolt any more.


6

In general, crank fixing bolts need A LOT of torque. This chart list torques for several varieties of crank arms. (I suspect you have a variety of Octalink.) You're probably looking at something in the neighborhood of 350 inch pounds, which would be 35 pounds applied to a 10-inch lever arm. Too much force and you shear the bolt. Too little force and the ...


5

I bought a torque wrench after writing off a the bottom part of a set of Fox 36's: Those four little bolts at the bottom hold the axle in place, and need to be tightened enough to stop it coming out, but not so much that you stress the clamp. I'd over-tightened them and apparently the fork legs had tiny cracks. The replacement legs have a metal shim to ...


4

Crank bolts. They need to be really torqued, but you're always wary of over-torquing, so a torque wrench provides a good confidence factor.


4

Here's a page that tells you everything you want to know about torquing bike parts. It's by the recognized leader in manifacturing bicycle specialty tools, including one of the more popular torque wrenches. (Park Tool)


3

I love my Torque Wrench. It takes away the guesswork of being sure you are tight enough. I picked up one from and off brand that was calibrated in inch/lbs, and it wasn't as expensive as the park version. If you are no pro and working with carbon fiber, you need this tool.


3

While torque specs do definitely still matter with steel and aluminum parts, they are not nearly as sensitive to it as carbon parts are. We often mount an aluminum stem on a carbon steerer tube, or handlebar. It is the torque spec for the aluminum stem which matters most, but the bar will also have max torque spec, and the parts used must allow the same ...


3

I watched your video, and have to confess to a bit of a laugh when you picked up the crank, in what looked like a WTH moment :-) Some cranks have only a very light cap holding the crank arm laterally, so if the pinch bolts loosen, the crank could fall off before you notice. Square taper and one-key release, or other cranks are a different story. Daniel is ...


3

I admit I never use one... Still, for certain applications, specific tightening torque is specified. Things like crank-retaining nuts, quill-stem retaining bolts... Crank bolts on models with removable chainrings... That sort of thing. Some people have a good feel for "tight enough", but others may be ham-fisted enough to break or strip fasteners without ...


3

You want to make sure that it will serve the range of torques that you will realistically be using. Most bicycle tasks will require quite a low torque (e.g. 8 Nm) but occasionally (crank bolts, pinch bolts) you'll need much higher torques (e.g. 50NM). I have 2 torque wrenches, a 'sensitive' one which ranges from about 5NM to 20NM (in fine graduations) and a ...


2

I am with yourself - no need (unless you have a very expensive pro roadbike). However there are new 'carbon fibre' components that have changed since the good-old-days. These can have things such as 'helicoil' inserts glued in to them. In the olden days it was just chainring bolts that were tricky to get right without a torque wrench. Nowadays you can do up ...


2

You want a torque wrench that's made for the range of torques that you expect to use. A wrench with too large a range will give you limited precision in the range you need. Basically, it will be harder to tell if you are applying the correct torque. One that's too small won't let you apply the required torque. The accuracy of the reading may also be ...


2

Saint Sheldon had an opinion on using a torque wrench ... Experienced mechanics will strip threads as part of the learning process. After you've stripped a few, you get the "feel" for what a given thread diameter and depth of engagement can take. This is a very worthwhile skill to learn. Bicycles are meant to be user serviceable without needing a ...


2

Like Jason S said above, you've got a GXP ("Giga X Pipe") style crank, made by SRAM (possibly labeled Truvativ on it). The design is two bearing cups screwed into the frame, which support a shaft that goes through the cups affixed permanently to the drive side arm, and the non drive-side arm attaches via a self aligning screw. It's actually a very ...


1

This is the tool you want, combined with any torque wrench with the proper range. There are a number of applications where a torque is specified by the manufacturer, but no tool fitting for a torque wrench is available. The BBI Torque Wrench Adapter allows you to attach any "normal" wrench to a torque guage, and get an accurate measurement of the torque ...


1

Are they FSA SL-K cranks? Mine kept coming loose. FSA advised the use of loctite - 641 for the splines. I had a hard time finding this specific formula of loctite locally, but once I got some my crank stayed on for about a year until I upgraded.


1

I use a torque wrench because I like a little piece of mind, and have unfortunately ruined a few parts by over tightening. I have a Wright Tool torque wrench which is perfect. No complaints and no more broken components. You can pick one up for a decent price off ebay.


1

Set-torque wrenches are the nicest to use, but some (including mine) don't allow you to set torque when tightening a left-hand thread (left pedal, for example). Usually there's a corresponding right-hand thread to tighten at the same point in the assembly process so I do that first and just tighten the left-hand thread by feel. As previous posters have ...



Only top voted, non community-wiki answers of a minimum length are eligible