|Blue Loctite on BB threads??||Wise Guy|
May 10, 2002 9:57 AM
|I am trying to get rid of a ticking sound in by bottom bracket. I've tightened the chain ring bolts, the crank arms and retightened the BB which helps temporarily. A friend told me to put blue (non hardening) loctite on the BB threads. Does anyone know if this will help and if this is a good thing to do??|
|no, see attached thread:||lonefrontranger|
May 10, 2002 11:43 AM
|Do you have a Shimano BB? If so, some of the cheaper / older Shimano BBs were/are prone to the Shimano BB creak - that sounds like the ticking noise you described. This had nothing to do with the threads as I recall, it was simply that the torque would very slightly ovalise the bearing races (??) and cause the axle to sway slightly within the cups under hard load (seated grinding / standing climbing) You only hear it when climbing or going relatively slowly under load, right?
in this thread I explain why I personally would never blue (or any other color) Loctite a BB. Use ti-prep or anti-seize instead.
Not intended as flame-bait, just as an observation; haven't had any unusual creaks, squeaks or rattles since switching over entirely to Campy stuff. My Shimano BBs have all creaked at some point, MTB, road AND 'cross. My Ultegra levers both developed the Ultegra rattle within about six months of each other, and the stupid cheap shroud dustcap that causes this had to be epoxied in place on both of them. My Rolf Vectors made an ear-splitting rendition of the Rolf Hub Warranty Noise.
Of course as I say this, I'm kind of semi-worried about one of my 3 C-10 chains exploding, as has happened to others (tho I don't use the "im"Permalink). Your results may vary.
|re: Blue Loctite on BB threads??||grzy|
May 10, 2002 1:42 PM
|Tefolon tape and a torque wrench should address your BB problems - assuming that's the problem. Many times the creaking noise comes from places other than the BB. Seatpost, quill stem, el cheapo skewers, etc. can all make noises in synch with your pedaling.|
|grzy, question (or TJeanloz)||lonefrontranger|
May 10, 2002 2:02 PM
|The reasoning for the Dreaded Shimano Cheap BB Creak that I posted above was the "stock" reasoning taught me by the shop owner I worked for, but I was never quite sure if that was one of those "I-don't-know-so-I'll-just-invent-some-BS" type of responses that we shop mechs typically keep handy ;-) I honestly tried not to ever BS a customer, so I've always kinda wondered. I've never heard any real validation from an engineer / industry person behind this. I can't imagine that the bearing race itself would actually sag/ovalise under torque, would it?
What I'm getting at is (if anyone knows) what is the exact, ultimate cause of the Shimano cartridge BB creak? It typically only occurred in lower end Shimano cartridge BB's, but it is/was very common, and was 99% of the times traceable to the BB. It would go away for a few months if the BB was replaced, but most riders (like myself) simply learned to use a higher-end or aftermarket BB or simply tune it out. I recall endless streams of these things, both returned to the shop and that I rode / replaced / threw out / sacrificed dead chickens over.
I don't know if these still creak anymore because a) I no longer work in a shop, so I'm not that close to these developments, and b) I use Campy.
And man, was that ever an annoying noise.
|grzy, question (or TJeanloz)||gtx|
May 10, 2002 2:22 PM
|I was working as a wrench in shops when those first came out. The noise comes from where the non-drive side cup comes in contact with the bb cartridge body. I talked to someone at Shimano and they told me to put Permatex non-drying gasket sealant in that area. I've used that ever since--on tons and tons of bbs--and it's cured them all.|
May 13, 2002 1:58 PM
|You've got a couple areas for things to loosen up on the BB - all due to precession (the rotating cyclic force applied by the crank). Torquing the BB correctly (75 Nm) and using teflon tape goes a long way towards keeping things in check. Once one of the cups becomes lose you have the opportunity for the BB cartridge to wobble inside the cup or for the cup to wobble inside the BB shell OR both. Now once things that aren't supposed to move get going tollerances increase in almost an exponential way - a little at first then lots and lots. I'd say that fundamentally the current BB shell is a design near the margin. Given a clean sheet of paper you'd most likely see a more robust design - larger diameter and probably a finer pitch on the threads, and a more positive locking arrangement. but the current standard is what we're stuck with. Interesting to note that early Merlins and Kliens (and others) had bearings pressed directly into the BB shell, but eventually gave up on their advances and fell in line with the industry stanard. |
Although the BB problem is fairly common there are several other sources of noise that give rise to a cyclic creaking noise. Much of the BB problem can be avoided if it is installed correctly with the proper "preventative measures."
|teflon tape works||DougSloan|
May 13, 2002 3:44 PM
|I used to have lots of clicking/creaking problems with a DA bb; since using teflon tape, never again have problems. I even use it with the Record bb just to be safe. No problems.
|Ditto on teflon tape||snuggleman308|
Jul 3, 2002 3:52 PM
|re: Blue Loctite on BB threads??||mackgoo|
May 10, 2002 2:05 PM
|I know you've probably checked this already but I thought I'd mention it. When I get a tick that just doesn't go away close inspection reveals that my crank is hitting the front derailuer cable end.|
|I'm glad you said that.||Spoke Wrench|
May 12, 2002 5:14 PM
|I'm embarrased to say how much time I once spent trying to find a "tick" that turned out to be the front derailleur cable hitting the left crankarm.|| |