Do I need a torque wrench to install a Shimano Hollowtech II type BB, or can I just get by with a tool like the ParkTool BBT-9? Note that I have a small torque wrench that goes up to 16 Nm (~140 in-lb) for use elsewhere, but not one that can be used for a bottom bracket.

What about some of the other BB/Crank systems, specifically Calmpy Ultra Torque, would I need a torque wrench for that install?

on steel and aluminum frames, it's pretty hard to over-tighten the cups due to the amount of threads engaged and the overall size of the 'screw'

I don't believe a torque wrench is needed at all, but some hand sense is needed. If you're experienced you should be able to read the recommended torque and approximate it based on judgment and experience. For a newbie, this might be more of a problem, but as AEO said, it's a large thread and virtually impossible to strip.

Thanks for the responses. I'll pick up a ParkTool BBT-9 and give it a shot. Hopefully I have enough experience to do this and have developed enough of a "hand sense"... if not, this will certainly add to both.

I did my BB by hand sense. I Didn't want to strip or overtighten. 2 weeks later, it was a little lose... snugged it up again. All good for the 1k miles so far.
If you're unsure, stay safe and just check it later.

You want it way beyond snug. The recommended torque of 40 - 50 ft-pounds or so is pretty much all you can apply by putting your full arm strength onto the wrench handle.

Once again.

If you don't know what proper torque even remotely feels like. Use a ****ing torque wrench. Come on people. Tools exist for a reason.

I'm afraid I side with operator on this one despite my reliance on not using torque wrenches in my normal bike work. Any adult is easily capable of exceeding 50 ft-lbs with the typically 12 inch long 1/2 inch ratchet used on the BB socket. The "hand sense" mentioned before is used by longer time mechanics all the time. But the feel for this came from frequent use of a torque wrench early on while in the learning stage. Once you get the feel for certain amounts of torque then your torque wrench can collect dust except for certain special cases. But until then it's well worth getting one and using it a lot as training to develop that sense of feel.

This with emphasis on ****.

Enjoy

Agreed... torque wrench it is. Now if I can just fine one of the ****ing variety.

Would something like loctite help in cases of inadequate tension?

no, loctite is not a substitute for proper torque

In my experience, the biggest danger installing a HollowTech II BB is with the crank arm fixing bolt. Those things take almost no torque and strip if you breath on them to hard. Or maybe I'm just ham-fisted.

Loctite is so seldom actually required that I've got a small tube that has lasted me for almost 20 years. Greased threads to combat corrosion and the proper torque is the proper option for 99.99% of threaded joints on a bicycle. And actually I don't even use thread locker on the .01% where it might be useful. Oddly enough I have yet to have those parts come loose and fly off the bike.

Correct.

Finger tight is all you need. There's a reason why they make the bolt and the tool to install it out of plastic. It's not a square taper bottom bracket, it doesn't need to be torqued to smithereens. All it's there for really is to hold the arm in place while you torque down the pinch bolts.

Well, yeah.


I guess the plastic part thing should have been a clue, but in my ongoing quest to figure out every way you can mess things up, I messed this up. Lacking the magic hand feel, I do use torque wrenches, and since I had a torque specification for the fixing bolt, I grabbed my small click-type torque wrench and gave this a go. At which point faulty tool operation on my part combined with my lack of hand feel (or even ballpark intuitive sense) for what 6-13 inch pounds feels like, and I stripped the bolt.

In a related story, I've got an FSA Gossamer crank with MegaExo bottom bracket that has an aluminum fixing bolt. Somewhere along the line (I think I'm innocent on this point) that got over-tightened and the first time I tried to remove it (quickly loosing my previously claimed innocence) I rounded off the inside flats and had to a screw extractor to get it out.

Hence, I have an uneasy relationship with fixing bolts.

Harbor Freight has a sale on clickers for <$20.

Screwing up is the best way to learn, but unfortunately it's not the cheapest!