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Torque Wrench?


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A couple of Micrometer-Adjustable Click-Style Torque Wrenches that cover probably the entire range of torques you'll encounter on your bike:




85555A214 30-250 lb-in (4-28 N-m) $116

85555A311 5-75 lb-ft (10 - 105 N-m) $152


The mcmaster catalog doesn't specify the manufacturer name, but they are good names (I think one was a Snap-On subsidiary).


You'll need allen-wrench sockets to go with them, if you don't already have them.


When shopping for these, I checked for the range of torques that you need. Here are a couple of extremes:


Lock-nut when you do a valve-adjust is 8 Nm

Rear wheel lugnet is 105 Nm

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While that latter wrench may be rated to 105 nM, no way would I use it there. You really need one more that will go into the 150 nM range.


Expensive, I know, but you need 3. A 1/4" drive, a 3/8" drive and a 1/2" drive, to cover the full range of torques. You probably only want to operate a given wrench in the middle 50% of its rated range.

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Ed is correct. The wrenches are not as accurate near their rated extremes.


The Craftsmen wrenches are good enough for the amount use they will receive. Just remember to set them back to the lowest setting when not in use to keep them accurate longer.

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Calvin  (no socks)

Save a few dollars and look at a couple of pawn shops. I find tools all the time...Some a good deal, some at retail... dopeslap.gif

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I bought a sears wrench 3/4" that was on special for about $80.00. The fine adjust ring had the numbers painted or printed on in silver. When i touched with an oily finger the numbers started rubbing off. I Took it back and got my money back. Avoid anything that does not have the calibrations engraved or stamped in the metal.

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Ed is correct. The wrenches are not as accurate near their rated extremes.


That might be, but it isn't what the certificates that come with the wrenches say.


The smaller wrench I listed, from CDI Torque products (that's the Snap-On company) has a specified tolerance +/- 4% CW and +/- 6% CCW from 20% to 100% of capacity clockwise. That's the tolerance, but what's much better is that the wrench comes with an individual data sheet showing the actual test results for my particular wrench. It shows 18 measurements (3 reps each CW and CCW at 20%, 60% and 100% capacity). None of the measurements, not even those at full capacity, erred by more than 1.5%.


CDI recommends that the calibration be checked after 6 months or 5000 cycles (which almost none of us would actually do).


CDI puts all kinds of reassuring stuff on the certificate including the name of the tester, the date, claims that the measurements comply with ASME B107.14M-1994, and claims that the tests were made on a Suretest P0085A/P0059A calibrator with an accuracy of +/- 0.25%. I haven't checked all that out, but it looks like more than just a marketing ploy to me.


The larger wrench, from Armstrong Industrial Hand Tools, is rated +/-4% accuracy, in both directions, from 20% to 100% of capacity. So it claims to be as good as the CDI at full capacity. But it doesn't come with an individual data sheet like the CDI wrench, and its specs are guaranteed only for 90 days. The booklet for this wrench does suggest that if you store it for an extended time, you should turn it to its lowest setting.


As you say, maybe the wrenches aren't any good near their rated extremes, and that might be true when they're old, but I'd bet the manufacturers who put those individual calibration data sheets in the box can be trusted that they're right at least when they're new.

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Avoid anything that does not have the calibrations engraved or stamped in the metal.


I bought a 3/8" drive from Sears.

The metric scale is hard to work with as you have to add or subtract a correction factor to get the correct setting.

It's a pain in the ASK frown.gif

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I have yet to see a certificate get pulled out of a tool box to tighten a bolt. It is the wrench that does that.


It really isn't about the accuracy of the wrench in its range. Even 5% off isn't really gonna mean all that much. Wrenches come sized for a reason and using one at its maximum rating time after time is just poor practice.


I have made my living with tools since 1959 and still have the 1/2" drive, deflecting beam torque wrench I bought at Sears back then so I could torque the head bolts on my '59 Corvette.


Tool sales people, including your Snap-On dealer will give you a simple rule for picking a wrench so that you will continue to get good service life out of the tool.


1/4" (6mm) bolts and smaller, 1/4" drive wrench

5/16 to 7/16" (8-10mm), 3/8 drive wrench.

1/2" to 5/8 (12-16mm), 1/2" drive.

Above that, 3/4 or 1" drive depending on your budget.


For casual use by the home mechanic, deflecting beam wrenches are plenty good enough and a good deal cheaper. They do require a little more skill to use, but that is what the bench vise is for.


Truth be told, with the exception of wheel lugs and certain internal components on an engine, like the cam bearing caps on my Blackbird or VFR, I rarely dig out the torque wrench. I'll use one where I deem it appropriate, but, 50 years of experience has given me more than adequate feel for this stuff.

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None of the measurements, not even those at full capacity, erred by more than 1.5%.
That was my experience when I (just for amusement) used an electronic torque gauge to check my several clicker torque wrenches (all Craftsman) of various ages, but none less than 10 years old and some many more. None had ever been calibrated since purchase and I was shocked to see that they were all still quite accurate (within a few percent) throughout their range. I especially looked for increased error at the high and low ranges but couldn't find any of significance. I have to admit that this was not what I expected and certainly contrary to conventional wisdom, but what can I say...
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Silver Surfer/AKAButters

I have three Craftsmen wrenches and try to use them near the middle of their ranges when possible.

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