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Cathedral City, CA
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The idler cages are fairly thin metal. The rule of thumb for screws is that you need an engagement length as long as the diameter of the screw plus one thread. This allows you to be able to develop the full strength of the screw. However, given a fairly small screw size and thin material, it could be safer to use low torque and a threadlocker rather than higher torque alone. I would think that it would greatly reduce the chances of striping the threads.
 

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What the what???
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I generally just apply grease to threads. If I have a bolt on something that is persistently working loose, I might apply some Loc-tite (Blue) to it, but that doesn't happen very often.

Otherwise, as FBinNY mentioned, only for bolts where Loc-tite was applied at the factory. One that comes to mind is the bolt that holds the derailleur pulley wheels. Since they only thread in to the other side of the cage and don't technically have a dedicated bolt, I can see where a little Loc-tite wouldn't hurt.
 

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....One that comes to mind is the bolt that holds the derailleur pulley wheels. Since they only thread in to the other side of the cage and don't technically have a dedicated bolt, I can see where a little Loc-tite wouldn't hurt.
Even here, component makers can and do engineer not to need Loc-tite. My basic rule still applies, if the maker didn't use Loc-tite at the factory, it shouldn't be needed later.

Of course common sense has to prevail. If, for example, the threads were compromised, or I had a problem of chronic loosening, then it's Loc-tite to the rescue.

In most cases there's no real reason not to use Loc-tite, other than possibly more difficult disassembly later on, but it's easy to fall into the trap of over dependence on adhesives as a crutch for bad design or practice.

IMO- with the exception of the very most pure race bikes, bikes can and should be designed without dependence on Loc-tite type products. Not that they're inherently bad. But user serviceability should be a high priority, and too many end users neither have the right products, nor do they know how to properly prepare the fasteners and apply the products.
 

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I don't use thread lock on any of my bikes, but I find it's a must on my cleat bolts.

And nothing but blue Loc-tite.
 

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No Crybabies
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and...

In bike work, where do YOU use them? How do you make the determination?
I use:

Phil or Park grease
low strength Loctite
copper anti-seize

Grease for 99% of threads. Torques more smoothly, comes apart later.

Anti-seize on aluminum and titanium threads. If I'm being diligent, I use it also on pedal threads.

Only place I can recall using Loctite was on my Italian thread bottom bracket, after the drive side loosened one time, and for mtb bolts that hold the brake disc on. Use it a lot on the threads on my hitch bike rack, as I've lost many small screws from it.

Oh, when I do the FC 508, I prepare the bike with Loctite on many threads (like stem bolts, crank bolts, etc.), as the roads are bumpy, there are 60+ mph descents in the dark, and it's a race. Don't want to take chances.
 

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I use the below on my bikes. Can someone explain to me the differences between the 2 greases? I use the Shimaono grease in the threads of the BB and the teflon grease elsewhere (screw threads, bearings).

Use the Loctite 222 (which came with some Festo stuff from work) on small screws in dropouts and jockey wheels.

Your benefits:

Ideal for low-strength threadlocking of adjusting screws, countersunk head screws and set screws
Good on low strength metals which could break during disassembly, e.g. aluminium or brass

Technical Data:

Maximum thread size: Up to M36
Strength: Low
Breakaway torque M10 bolts: 6Nm
Fixture time steel: 15 min.
Fixture time brass: 8 min.
Fixture time stainless steel: 360 min.
Service temperature range: -55°C - +150°C


 

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...just recently, I've found that my removable valve cores in my Continental tubes keep unscrewing when I unscrew the (Lezyne) pump head and they blast across the room. When that happens (and I can find it,) I put some Loc-Tite on, as I don't need them to be removable.
I hadn't thought of that. My Lezyne pump has done that with the valve cores on my Vitoria tubs. It's a massive f*cking pain in the 'rse when that happens in the middle of gluing a tub.

Repped :thumbsup:
 

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I hadn't thought of that. My Lezyne pump has done that with the valve cores on my Vitoria tubs. It's a massive f*cking pain in the 'rse when that happens in the middle of gluing a tub.

Repped :thumbsup:
If you read the instructions for your pump you would have known form the start. It's one of the first things in big bold letters. RTFM :thumbsup:
 

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Discussion Starter · #30 ·

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Actually, that's how a thread locker works. Threads are not perfectly round or have perfectly formed peaks and valleys. Loctite and other compounds fill the imperfections. After it's cured, it prevents the screw from rotating. Contrary to what some people think, it isn't a glue.
Grease actually works in a similar way. Many people think that by using grease the parts might come loose, but the opposite is true. While grease doesn't "cure" like thread lockers, it fills in the gaps & imperfections & has the added benefits of preventing rust & making it easier to disassemble when you need to. Kerry said that nothing falls off his bike. Well that's not quite true for me. I fall off on rare occasions, but I try not to make a habit of it. Maybe I should use thread locker on my ass.
 

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Cathedral City, CA
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Actually, that's how a thread locker works. Threads are not perfectly round or have perfectly formed peaks and valleys. Loctite and other compounds fill the imperfections. After it's cured, it prevents the screw from rotating. Contrary to what some people think, it isn't a glue.
Grease actually works in a similar way. Many people think that by using grease the parts might come loose, but the opposite is true. While grease doesn't "cure" like thread lockers, it fills in the gaps & imperfections & has the added benefits of preventing rust & making it easier to disassemble when you need to. Kerry said that nothing falls off his bike. Well that's not quite true for me. I fall off on rare occasions, but I try not to make a habit of it. Maybe I should use thread locker on my ass.
You know, hitting the quote button is easier than doing Cut and Paste...

Using gease or an anti-seize compound allows fasteners to be properly torqued. That's why they tend not to come loose.
 

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You know, hitting the quote button is easier than doing Cut and Paste...

Using gease or an anti-seize compound allows fasteners to be properly torqued. That's why they tend not to come loose.
Yup! That's another reason. Happy that I used the quote button for this one?
 

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Cathedral City, CA
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Yup! That's another reason. Happy that I used the quote button for this one?
It makes it easier to follow where things come from and the accompanying train of thought...
 

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Someplace where I've used Loctite to great effect is on my lawn mower & snow blower handles. Those dang things were always coming loose even if I used grease. They both vibrate like hell. Nice, cushy bar tape keeps my hands from going numb.
 

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The idler cages are fairly thin metal. The rule of thumb for screws is that you need an engagement length as long as the diameter of the screw plus one thread. This allows you to be able to develop the full strength of the screw. However, given a fairly small screw size and thin material, it could be safer to use low torque and a threadlocker rather than higher torque alone. I would think that it would greatly reduce the chances of striping the threads.
Thank you for clarifying. All these "I'm an old-timer and I've always done it this way" comments were not particularly illuminating. You are the first and only to mention the quite-reasonable consideration that grease keeps fasteners in place with torque, whereas Loctite holds them in place by filling spaces between the threads. Actually pretty simple once you explained it. Thanks.
 

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Of course common sense has to prevail. If, for example, the threads were compromised, or I had a problem of chronic loosening, then it's Loc-tite to the rescue.
Maybe the better practice is to put the Loctite on before the fastener falls off and rolls into the bushes when you are 23 miles west of nowhere? :)
 

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Matnlely Dregaend
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Campagnolo uses some form of loctite from the factory on pretty much all small screws to keep them from turning. If I do a Ti replacement of one of those screws I'll sometimes add loctite, but I've found it's rarely necessary. The only place I've found to definitely need it is the hirth joint bolt on cranks.
 
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