MTB0007 Posted September 9, 2009 Share Hi Why would a stem bolt - (Pinch BOLT) make a snapping sound when loosening?The steerer is carbon and the stem is scandium...Any ideas, I know from working on motors - this is usually the threads loosening, but on a bicycle ???????????????/NEWBY00072009-09-09 04:31:14 Link to comment Share on other sites More sharing options...
Bos Posted September 9, 2009 Share same thing... Link to comment Share on other sites More sharing options...
SwissVan Posted September 9, 2009 Share Bolt and "nut" thread are metal. And probably well secured with all the excess sodium and other chemicals excrected after drinking those expensive commercial energy drinks... SwissVan2009-09-09 04:46:52 Link to comment Share on other sites More sharing options...
MTB0007 Posted September 9, 2009 Share I hope its just threads.. Link to comment Share on other sites More sharing options...
Delgado Posted September 9, 2009 Share Do you ride a Cervelo? Mamil 1 Link to comment Share on other sites More sharing options...
SwissVan Posted September 9, 2009 Share Well chances are if it made the snapping sound the bolt is loose at least... Link to comment Share on other sites More sharing options...
MTB0007 Posted September 9, 2009 Share I ride a KHS Mtb..The bolt is loose...... and refitted.. no prob... Link to comment Share on other sites More sharing options...
Johan Bornman Posted September 9, 2009 Share Interesting that you observed it, most people don't question those little trivialities that make life so interesting.The bolt is elastic - in tension, in torsion and in compression. The latter state is not achieved but when you tighten a bolt, it stretches and it twists. Stretching Im sure you understand, but the twisting is the snapping noise. When a bolt is tensioned, the top part of the thread is slightly ahead of the bottom part of the bolt. And remains in that twisted position until it is released. When you loosen the bolt, the top part of the bolt at first goes past the bottom part and then suddenly the bottom part breaks loose from its static friction position and shoots back to catch up with the top part. That's the snap. There is more friction in aluminium than in steel on steel, hence the stem's pronounced tendency to snap. You'll also find it in other bolts on the bike. Mamil 1 Link to comment Share on other sites More sharing options...
MTB0007 Posted September 9, 2009 Share Hi Johan Thanks - makes sense..When is the shock service course ???? Link to comment Share on other sites More sharing options...
Mornay De Doncker Posted April 16 Share Greetings, so I've found that cracking/snapping noise when loosening my rear flat mount caliper bolts to realign the caliper. Is that noise something to be concerned about ? Does it need grease,copper compound or blue threadlocker on assembly to avoid noise ? Link to comment Share on other sites More sharing options...
Ozzie NL Posted April 16 Share My guess would be that there is dirt and sand in the thread but that would be a little too obvious? There should not be any noise coming from those bolts when loosening or tightening. Link to comment Share on other sites More sharing options...
droo Posted April 16 Share https://en.wikipedia.org/wiki/Galling Lubrication (anti seize, grease or loctite) will generally prevent this, which one you use will depend on tightening torques among other things. On brake bolts, low strength loctite is the way. DieselnDust and NC_lurker 2 Link to comment Share on other sites More sharing options...
Mornay De Doncker Posted April 16 Share Thanks for the response and the link, do appreciate 👍. Was helpfull indeed and helped me made my choice of adhesive/lubricant. Regards. Edited April 16 by Mornay De Doncker Link to comment Share on other sites More sharing options...
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