Bicycle Mechanics - Grease, Teflon Tape or Loctite for Bottom Bracket Cups?

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fast_track
06-06-08, 01:30 PM
After a long search of the forums I have found a lot of conflicting information as to what to apply on the cup threads when installing a cartridge bottom bracket.

It's a 3 piece Miche Primato Pista 110mm/ISO BB in case the make and model matter to anyone, with BOTH cups being adjustable.

I've looked at several manufacture's websites as well. Some suggest grease (I already have a tube of Phil Grease) Others suggest Teflon plumbers tape and while others suggest using Loctite 242 Blue.

As it is an ISO BB, everyone suggest not putting grease on the taper or the inside of the crank for ISO so it doesn't go on "to far" and deform the taper. That makes sense to me. Go dry at the connection point for ISO square taper. I guess that differs from ISIS where you would use grease...

Anyway, as for the cups on the BB I am open to suggestion.... What do most mechanics do? Thanks!


Metaluna
06-06-08, 02:31 PM
For what it's worth, Phil Wood BB's have adjustable cups on both sides as well, and they recommend Loctite (and actually include a tube with the cups). However, I've used all three substances (grease, tape, Loctite) at various times on various types of BB's and all were satisfactory, but then I tinker with my bikes a lot so my BB's tend to get removed and reinstalled too frequently to say which one works best over the long haul.

One thing I don't like about Loctite is that it leaves hard crusty gunk all over the BB threads which is nearly impossible to remove without damaging them.

fast_track
06-06-08, 02:45 PM
I too noticed the Phil suggests Loctite and I was wondering if it was because their cups are adjustable as well, vs others that are not. I know its hard to compare a Phil ($120+) to a Miche ($25) BB in overall quality, but in theory the installation would be similar as the cups are similar.... I'm wondering if it is the right direction to go for cups that don't have a drive side flange (or what ever you call the lip).... Haven't used Loctite on anything in years... Didn't realize it got crusty, thought is stayed gummy, thanks for the tip.


HillRider
06-06-08, 02:54 PM
Loctite hardens in the absence of air which is how it keeps threads from loosening. For most bottom bracket installations it is not needed unless the maker specifically recommends it. .

Grease (some use anti-seize which works just as well) is usually sufficient and teflon tape is good if the threads on either the bb or shell are a bit sloppy or the bb tends to squeek.

BTW, hardened Loctite can be removed with acetone with no damage to the threads.

Joshua A.C. New
06-06-08, 03:26 PM
I've also gotta say: I've never actually seen a crank damaged from a greased spindle and every LBS I've ever talked to greases them. New Shimano BBs come pre-greased even.

Grand Bois
06-06-08, 05:58 PM
I greased the threads liberally when I installed a Miche Primato BB in my '59 Carlton. The rings are aluminum and they are in a location that's likely to get wet. The grease helps prevent oxidation, which can cause the rings to get stuck, just like with aluminum seatposts and quill stems. I doubt that they will ever loosen themselves. The threads are cut so that they are a tight fit. I couldn't turn them with my hand.

http://inlinethumb13.webshots.com/28556/2692098340068014369S600x600Q85.jpg (http://good-times.webshots.com/photo/2692098340068014369LGCYtu)

operator
06-06-08, 06:04 PM
I too noticed the Phil suggests Loctite and I was wondering if it was because their cups are adjustable as well, vs others that are not. I know its hard to compare a Phil ($120+) to a Miche ($25) BB in overall quality, but in theory the installation would be similar as the cups are similar.... I'm wondering if it is the right direction to go for cups that don't have a drive side flange (or what ever you call the lip).... Haven't used Loctite on anything in years... Didn't realize it got crusty, thought is stayed gummy, thanks for the tip.

Phil suggest loctite because that's how it stays in the frame because of the way their bb is designed. Anyone else using loctite for regular BB installs (except for maybe problematic italian shells) is not a real mechanic.

It's a paint to take out, pain to remove and above all completely and uttterly unecessary.

You'll notice barnetts recommend this - 100% bad advice.

Tabor
06-06-08, 06:07 PM
I use the Phil Woods grease... personally.

Deanster04
06-06-08, 09:23 PM
If you are worried then use a torque wrench to install and don't over torque. Grease...

fast_track
06-06-08, 09:31 PM
Thanks for the tips. Sounds like the PW grease I have is the way to go.

John E
06-07-08, 06:53 AM
My vote:
1) fixed cup of ISO or Swiss threading (LH-threaded drive side): grease, since these cups are self-tightening, anyway;
2) Italian or French fixed cups: a small dab of blue Loctite, since these cups are self-loosening;
3) adjustable cups: grease, unless one really has a problem with self-unadjustment, in which case Loctite is the logical solution.

tellyho
06-07-08, 08:15 AM
I always start with grease, Teflon is my back-up in case I have a poor fit or creaks. I see NO reason to pay crazy money for Phil grease, though. Just the tub of auto grease does it for me.

Grand Bois
06-07-08, 09:00 AM
My vote:
1) fixed cup of ISO or Swiss threading (LH-threaded drive side): grease, since these cups are self-tightening, anyway;
2) Italian or French fixed cups: a small dab of blue Loctite, since these cups are self-loosening;
3) adjustable cups: grease, unless one really has a problem with self-unadjustment, in which case Loctite is the logical solution.

He's not talking about an ordinary cup and cone BB. This is a Miche Primato track BB that mounts like a Phil, but has aluminum rings. Both sides are adjustable.

nitropowered
06-07-08, 06:26 PM
Grease unless it is a double adjustable cup like phils or in your case the miche

sbarner
08-17-09, 06:56 PM
This is a stale thread now, but I recently installed a Miche Primato BB in a Gunnar Crosshairs for a triple crank. I really reefed on the cups, but they moved twice on me, walking inward until the inner chainring started rubbing against the frame. Obviously, after the first time, I cranked down on the cups as hard as I dared (I'm no wimp, and have decades of experience as a bicycle and auto mechanic), still, the cups moved again. At least the second time, I had the tools with me! The cups were a good fit, barely hand-turnable. If I were to use the BB again, I would not grease the threads, but I would try Teflon tape and, if that didn't work, Locktite.

nitropowered
08-17-09, 07:46 PM
I just use grease. Locktite if its a problematic italian cup or dual adjustable cups and they keep coming loose.

I never grease the tapers of the spindles.

neil0502
08-17-09, 08:15 PM
(I'm no wimp,

Wimps never think they're wimps.

Just sayin ..... ;)

arborohs
08-18-09, 03:09 PM
what does Miche say?

Panthers007
08-18-09, 04:22 PM
The only time I've used Locktite on a bottom-bracket was recently. I put some 'blue' Locktite on the fixed-cups I pressed into my 3-speed frame for the new Ashtabula-style bottom-bracket. Other than this one application - I use Teflon-grease. It's never failed on me yet.