Hitchcocks Forum

I have often wondered if I should buy one - which type - and how useful they are; have relied so far on feel/hand-adjustment. What is the experience of the forum with these? Is it a must have?

I noticed that torque values given for the Bullet 500 can be (unfortunately) sometimes quite different depending upon manual consulted, eg

(Pete Snidal) rocker bearing stud nut (3/16'') kg-m 0.40 LB-inch 33
(Work Shop Manual Bullet) gives kg-m 1.30 LB-inch 112.0 for same item.
Also quite different values for rocker box stud nuts, depending on manual....
C

I've had two torque wrenches for years; IMHO they are essential. I have two to cover the wide range of torque values on fasteners on bikes and cars I've owned over the years. That said, I'm not obsessive about torquing all fasteners to spec, even if specs are available. Lower value torque settings I do by feel; key settings such as cylinder head bolts, anything that has stretch bolts, anything that needs a defined preload etc I use a torque wrench for. Just what I do; others will have different opinions. Oh, and beware of spurious accuracy using a torque wrench that hasn't been recalibrate for years. My best one is a Norbar; I would go for one of decent quality or not bother. Price is a pretty good guide.

I have two torque wrenches as well, I always un-tension them after use and put them back in their boxes.
I found out a long time ago especially when torques less than 15ft lbs are specified that not using a torque wrench can lead to an expensive disaster.(The camshaft bearing mounts on a very old pre 2nd World War MG 1600cc sports car.)

yes buy a torque wrench if you are often working on nuts/bolts, "feel" does not work, it does many jobs yes (40yrs+in the job), think this will lead to some "advice"

I have two as well. I use them pretty much in the same places as Rattlebattle. I also use the small one when tightening case screws. As they are usually socket head cap screws these days it's easy to get carried away and strip the alloy thread.
If you can't find specific values for particular fastenings there are tables of recommended values for sizes and threads in different metals available. Just Google.
I second Papa to un-tension them after use or they will loose their accuracy. By rights you should have them re-calibrated regularly but in a home workshop this isn't probably necessary.

The required torque on any screw thread is determined by its diameter and the material; thus we could look up the required torque from any reliable source online. Aluminium is of course somewhat softer and weaker than steel.



I also have two torque wrenches. The old large one needs to be cracked off a few times in the vise before each use as it locks itself up in its case; test your wrench before use, they like to be oiled too. The small one is a cheap bending bar job; these things are pretty reliable and reasonably accurate for case screws and the like, though probably not up to doing a cylinder head; the purpose here is to stop me over-tightening things.

And I'm simply going to continue the consensus. I have two Halfords "professional" torque wrenches which were supplied with calibration certificates and I've checked them for accuracy several times over the years that I've had them. Torque wrenches are not cheap, but neither are thread repairs.

Jefrs, could you enlighten us how to test a torque wrench before use? I, for one, do not have the necessary calibration equipment.
If you wrench locks up in storage and needs " cracking off" I can't imagine it's the least bit accurate. The instructions on both of mine make no mention of lubrication being required.

Pete it's a waste of time,

I needed one last year to replace a cylinder head gasket, and was able to borrow one. However, I couldn't figure out how to set it so I used a piece of pipe over my socket wrench with a hole drilled twelve inches from centre of socket. To this I attached a luggage scale and pulled on it until it registered the required weight in pounds. Probably not ideal, but I didn't strip any threads and the bike seems to have plenty of compression.