Digital Torque Wrench

I, unfortunately, use feel on bicycles, though I would certainly use a torque wrench for a cylinder head on an engine. I have been turning wrenches professionally for all of my working life, so there is a fair bit of hubris there. I might be convinced to use a torque wrench on certain electrical connections though.
 
The case where you need to be really fearful with respect to torque are for small bolts on carbon-fiber frames and parts. You need to be pretty cautious with aluminum as well, though not as paranoid as with carbon fiber. With steel you don't need to worry very much. One more advantage of steel.

Don't even get me started about bolting a steel part to an aluminum frame.

Generally the torque limits on parts you really care about are very small, and I'd have to question whether a large automotive-style torque wrench is going to give accurate readings for that even if calibrated properly. Except for cranks and pedals and the cassette you are torquing less than 10 N-m. For some tiny bolts on the cockpit you might be less than 1 N-m (I recall for one Garmin mount the recommended torque was 0.7 N-m!).
 
I purchased torque wrenches when I bought ebikes. Now use them on bikes and van upfit.

After getting feel for proper torque, I am confident I have over-tightened in the past; especially smaller fasteners.
 
Ihor said:
Is overkill to loosen bolts, spray silicone, the torque them all, and do the same for the mid hub motor?
the specs on the Tern list all the connected parts and their nM.
Click to expand...
For most bolts that have torque specifications, that's a "dry torque." If you're lubricating the threads, then you need to reduce the applied torque by some amount - and I don't know what that amount is.
Maybe I'm misinterpreting your "spray silicone" phrase, though?
 
Mr. Coffee said:
The case where you need to be really fearful with respect to torque are for small bolts on carbon-fiber frames and parts. You need to be pretty cautious with aluminum as well, though not as paranoid as with carbon fiber. With steel you don't need to worry very much. One more advantage of steel.

Don't even get me started about bolting a steel part to an aluminum frame.

Generally the torque limits on parts you really care about are very small, and I'd have to question whether a large automotive-style torque wrench is going to give accurate readings for that even if calibrated properly. Except for cranks and pedals and the cassette you are torquing less than 10 N-m. For some tiny bolts on the cockpit you might be less than 1 N-m (I recall for one Garmin mount the recommended torque was 0.7 N-m!).
Click to expand...
Think of the stem bolts, the handlebar gear (such as brake lever or shifter clamps or handlebar grips), then the seat-tube collar bolt, then it is the seat-post bracket for the saddle, the chainring bolts... All these things could be overtightened and damaged. Then, there are the high torque parts such as crankarms or the cassette lockring.

1716307739286.png

An example. Note you are required to grease the parts then to apply the torque wrench.

1716307894587.png
to
1716307995321.png

Of course, anyone is free to damage their own bike. I could see the mechanics in the professional big LBS excessively using torque wrenches, as they were working on bikes that they did not own, and wouldn't like taking the responsibility for the damage done.
 
I have both a foot pound and inch pound torque wrench, neither are digital. I’ve never used one on my bike and don’t feel the need. I usually only use a torque wrench on critical items on cars and trucks, such as bearings a head bolts. I have started using them for lug nuts on cars to make sure I don’t over tighten them and I can change a flat if the need arises on the road side.
 
Click torque wrenches can go off calibration. They should be stored without any tension on the springs; set to zero. Experts say they should be checked after 5000 uses, or 12 months. Sitting in the toolbox is actually the worst thing for them. Frequent use they tend to stay true longer. Beam style torque wrenches tend to remain true for many years, unless metal fatigue sets in. Not likely for most.

I often use torque wrenches for bikes, MCs, auto, boats, fishing rods and firearms. The ratchet, click style and screwdriver style are no less convenient to use than any ratchet or driver. Beam style are less convenient due to no ratchet mechanism. But I own a couple beam torque wrenches, I use them to check the calibration of my ratchet T wrenches and drivers.

I don't own or use electronic digital torque wrenches. It's bad enough my bike needs a battery 🔋 😉
 
J.R. said:
, . But I own a couple beam torque wrenches, I use them to check the calibration of my ratchet T wrenches and drivers.
Click to expand...

I used my beam torque wrench to calibrate my hand to 30 foot pounds of torque using my Crank Brothers Multi-tool. 😂

146706-9f0ffd63a42dacddcdd8e2572cd6fe18.jpg
146707-3072976b1914e0c360b25715387f74b4.jpg
146708-b1a0fac62cc36fe339766edfa45aa557.jpg


Ouch. 😂

146709-27f602b29e0d1648bde76fbedf36df8d.jpg
 
J.R. said:
,.. Beam style are less convenient due to no ratchet mechanism.
Click to expand...

And if it doesn't have a square drive on both sides, you can't see the screen when your torquing upside down.

146706-9f0ffd63a42dacddcdd8e2572cd6fe18.jpg


I had to torque backwards to see the screen.
 
I've stripped too many threads with digital torque wrenches over the years. Unless you're willing to spend the $$ for a good quality mechanics grade digital wrench, do what I did and get a good beam type wrench.
 
Stefan Mikes said:
My Pro Bike Tool wrench has been with me for the last 4 years and served me well. The only thing the user of any torque wrench needs to do is to turn the handle back into the neutral position after use to decompress the spring. I don't care whether it is calibrated or not; it is still better than tightening things by the feeling. For instance, pulling the thread on a thru-axle will damage the fork or the frame beyond repair. Or, the axle is tightened too loosely.

I am surprised some Americans here still work by the feeling as I was sure it was a "measuring nation" :)

It could be WERA (I guess). Wera makes very expensive tools. They now have their manufacturing in the Czech Republic, which is a good thing as the country is famous for precision engineering. Moreover, the Czech have a great sense of humour and open minds, making them so different from the German!

Talking off-topic: I have seen e-bikes from a Czech brand by the name of Superior. The brand makes just excellent Shimano or Bosch based e-bikes! I could see a Superior e-MTB in person and was impressed!
Click to expand...
Woooooooooooo ... I'm going to be a Czech here and say ha ha!

 
Nice torque tool. And at five hundred it ain't all that much if you're working on a $8k+ bicycle.
Though, I think I'll still do it by hand feel. I haven't stripped, or had anything loosen up in a long, long time. I even have a carbon fiber bicycle, I believe it's a 2007 Specialized Roubaix. It was close to $3k new, I bought it last year for $100 in pristine condition. It even has the original tires--with no visible wear. Go figure! Fastest bicycle downhill that I've ever ridden, but it doesn't gear low enough for me. And that's a shame, because this bike fits me perfectly.
I'll hate myself for even thinking this, but maybe I could put a petite rear hub motor on it and have the hottest ebike -- ever!
 
I've got 3 torque wrenches, 1 is left unused as my calibration tool. I've thrown two away over the years when they go out by more than 5% - both a beam type and a dial up type. Admittedly the beam unit was OLD - a trusted tool and very much my favourite.

When working on carbon, I find myself going back to the manual to check the spec repeatedly - invariably I'm less than 5 degrees away from a bolt feeling too tight when I start getting nervous. But despite knowing I have reasonable " feel" , I'll keep using the torque wrench because - carbon is expensive!
 
Stefan Mikes said:
How expensive!
Click to expand...
The Wera tools are spendy but of extremely high quality.

The silca ratchet tool is less expensive and not bad for a lot of bicycle applications between 2-8 n-m, which is most of the bolts you deal with most of the time. But not those pesky ones under 1 n-m, which you generally just make barely finger-tight and then use a generous amount of blue threadlocker.

silca.cc

T-Ratchet + Ti-Torque Kit 2nd Generation

The world's smallest and lightest bicycle torque wrench with live 2-8nm torque measurement. Never break a component on the road or trail again.
silca.cc silca.cc
 
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