I'm replacing one sealed cartridge bottom bracket with another (Shimano UN-52 with a BB-6500) in a steel frame shell. Working from the Park website I removed the UN-52. Before installing the new bb they recommend (in this order) preparing the shell threads with:
1. a thread locker if "the frame shell is steel and the cups are either aluminum or steel lockrings"
2. grease or anti-seize compound
The BB-6500 has an aluminum lockring. I've never heard of a thread locker or asc. I checked the prices and found:
0.33oz (10ml) of Loctite 242 (the mentioned thread locker) is more than $10
4oz (120ml) of Park ASC-1 is about $10
3oz tube of Phil Wood waterproof grease is about $4.
I don't know how much gets used when applying it but 10ml of loctite sounds like it would do just one installation.

Are the other products that much better than grease?
Are they necessary if you avoid riding in the rain (but do get caught occasionally)?
Thanks

10ml is a good sized tube of blue Loctite. A little goes a long way. I haven't bothered with loctite on the bb threads. I just use grease.

I had that same bb on my Reynolds 853 steel LeMond Zurich. Replaced it once, and serviced it several times in 4 years (it rains a lot here in Florida). Never used anything other than a generous quantity of Park Polylube 1000 grease.

I do use anti-seize on my titanium Litespeed, tho.

Bob

Litespeed says grease is plenty adequate for threaded fittings for it's Ti frames but many of us use either anti-seize (get it at an auto parts store at 10% of the price of the same stuff from a bike dealer) or teflon plumbers tape on bottom bracket threads.

BTW, a 10 mm tube of Loctite will last most bike mechanics for years. You only use a couple of drops at a time.

I use anti-seize on my Ti frame, too. I figure: can't hurt, might help.

To get a bit more specific:

Metal Type of Anti-Seize
========== ===============
Stainless Steel -- Nickel
Brass against steel -- Nickel
Aluminum against steel -- Zinc
Monel, Inconel -- Nickel
Titanium -- Nickel
General purpose -- Aluminum-Graphite

https://www.sacskyranch.com/antiseize.htm
https://www.saftlok.com/safteze/antiseiz/nickel.htm

I don't believe that the Loctite serves the same purpose as grease or anti-seize.

Bob

It doesn't. My comment was in reply to the OP who noted that a 10 ml tube of Loctite cost $10 and might last only one installation. I wanted to assure him that it would last a lot longer.

This is the only thing my LBS uses on Ti frames. Silver stuff from NAPA. The smallest jar of the stuff will last several lifetimes.

Anti-seize is generally made to withstand high temps, so you would use it on exhuast manifold bolts (on your car )
Grease on all bike threads, including BB threads (and freewheels) is your friend!

"Anti-seize" that is "copper grease" is also used to prevent seizing when steel is in contact with aliminium and does prevent the chemical process which causes binding. Alu bar stems and steel head tubes for example.

I wouldn't use thread locking compound, it could be very difficult to get it out in the future. Grease or anti-seize is fine.

I would also not use thread locking compound on the BB bearing as it can be difficult to get out even when grease has been used. Water and dirt can get in the BB and lock up the threads making it difficult to get the BB bearing out after a while.

Anyone use ONLY teflon plumbers tape with no grease?

Yes, I've done it a few times. It works just fine.

One caveat, if you remove the bb for inspection, be sure to brush all of the tape fragments out of the threads before replacing the tape and threading it back in.

What of molybdenum?

it is a VERY small amount in the bike's frame... only an alloying agent in the steel.... as is the chromium.

here's the 411 on 4130, the most common Chrome-Moly steel...

https://www.azom.com/article.aspx?ArticleID=6742

note the tiny percentage of Moly in the alloy...

if you're talking of moly grease... it'll work, too.

I suspect he's referring to this:

https://www.grainger.com/product/ULT...AS01?$smthumb$

Bicycles are not a high-stress environment (i.e. not particularly high speed, high temperature, submerged, etc.) for grease, so it would probably work fine but not significantly better than a less expensive grease.

Well, first, Park Tools mentions loctite (blue/242/medium strength/non-permanent) first in their bit on installing bottom brackets (below).

The key things you are after are:

1) Making sure that the threaded joint doesn't loosen up in use. This is the function of threadlocker. Again, use the blue, medium strength, field serviceable, non-permanent stuff. Use blue, not red.

2) Making sure that the threads don't rust or corrode together and lock up or become weakened or non-serviceable. Grease or anti-seize work to prevent rust and corrosion. Loctite 242 is sold as a threadlocker and sealer, so I think it works for this purpose, too.

3) Making sure that in joints where both parts are similar metals, that they don't gall and cold weld (at least for bikes). So you're tightening a 316 stainless nut onto a 316 stainless bolt, and all of a sudden you can't turn the nut either way. The metals have galled and cold welded themselves, and your only next step is a hacksaw. 316 is notorious for galling, as is Ti. If you are threading a steel cup into a Ti frame, not so bad. If you are tightening a Ti nut onto a Ti bolt, USE ANTI-SEIZE. In non-bike apps, anti-seize also prevents high-temperature corrosion and keeps things like engine manifold and exhaust bolts usable. Anti-seize compounds have metal components (copper, nickel - even silver) that allow them to do their job.

The upshot is that threadlocker, grease, and anti-sieze all work. PTFE (Teflon(R) if it's Dupont's) tape (or better yet, PTFE paste - see Carroll Smith's comments on the difference in his book on fasteners) seems to work for some people. It may seal out water, but it doesn't protect the metal if water gets in. I say this as a PTFE "fan" - I used to work in the DuPont Plant that made Teflon(R) brand fluoropolymers like PTFE.

I'd use loctite, myself. In fact, I'm doing a build in the next month or so and will use loctite.

From Park:
Begin by preparing the threads of the bottom bracket. A thread locker may be used when the frame shell is steel and the cups are either aluminum or steel lockrings. A mild thread locking compound such as Loctite® #242 that is considered “service removable” is preferred. This means that the parts are removable with normal tools, without taking extreme measures. If no thread locking compound is available, grease threads heavily or ASC-1 Anti Seize Compound. For more on thread preparation see Basic Thread Concepts.

Always grease your BB on install and re-apply at least annually. Waterproof and/or teflon fortified grease is best. Titanium frames need anti-seize and regular attention as well.

I have my Shimano BB26 only half way in on the NDS. I used regular red grease. I also have a red lithium anti-seize I might try. Why do you say no red? Based on what I've read from you and others I might try a nickel anti-seize or thread lock. Thread lock doesn't sound right to me though. Wonder if I just have a tight fit and need a firm hold on the bicycle for tightening the second half of the NDS.

I went to Teflon tape after bottom brackets on both bikes needed replacing, one right after the other. It took four weeks to get the first one out, and six weeks to loosen the second. No threadlocker for me!


Torque the BB down, and either grease or Teflon will be adequate to keep it in place. Grease will wash out after some years if you don't pull and replace the BB roughly annually, and rust/corrosion will lock that sucker in place. Teflon tape just stays there.

What "grade" of threadlocker did you use? Some Locktite red and green grades are extremely strong and require heat to allow part removal. Grade 242 (Blue) or 222 (Purple) are weak enough to allow removal with hand tools. they are the ones that should be used for bicycle parts.

For over 45 years I've used nothing but grease and never had a problem. Once a year I pull the bottom bracket out to make sure the cups or threads haven't seized.

If it's a cartridge BB, that doesn't need to be serviced until it needs replacing, use anti seize mounting paste. Usually sold as copper grease, or some other (I use this one, locally sold, easier to clean than copper grease, a little bit cheaper, and also works fine).

Using a grease, in stead, will require annual re-lubing, to prevent seizing, especially if the bike is used in the winter. Using thread locker - makes sense if you have an Italian threaded BB, but otherwise not needed, best avoided.