That indeed would be the theoretical reason; not age. Good point. Next question: is there any useful and accurate *practical* guidance -- rules of thumb -- for retiring aluminum cranks, seatposts, bars, stems, and so forth?
Bills' reply reminds me of Grant's long-ago and wonderful metaphor: "Dolphin-like thighs" -- in contrast to sylph-like arms. Patrick Moore, who very strangely didn't think for a minute about the danger of riding his (What? I myself have owned them at least 15 years, and I got them ... 2nd hand? 3d hand? 4th or 5th hand? Pro 5 Vis cranks) during this afternoon's very pleasant fall ride. On Thu, Oct 25, 2018 at 1:48 PM Bill Lindsay <[email protected]> wrote: > Somebody claimed to have read somewhere that aluminum weakens over time. > > Patrick Moore asked for more details, and sounds skeptical. > > I took my materials science classes a fairly long time ago, but you are > right to be skeptical, Patrick Moore. Aluminum most certainly does NOT > change material properties with just time. Aluminum does weaken with USE > (repeated cyclical loading). You do not need to throw away your 20 year > old cranks just because they are old. You have to throw them away because > you ride an ENORMOUS number of miles and apply MASSIVE torque to them. > > Bill Lindsay > El Cerrito, CA > > On Thursday, October 25, 2018 at 12:07:57 PM UTC-7, Patrick Moore wrote: >> >> "Also, I read some somewhere(maybe a Riv Reader) that metals, and >> aluminum in particular, weaken significantly with age." >> >> I'd like to see the article and review the evidence. I myself have heard >> nothing said about age as such making metals generally, or aluminum in >> particular, less strong. Repeated bending, corrosion, yes, but not age >> alone. Anyone? >> >> Come to think of it, Jan in all his riding of vintage machines from 40s >> and 50s has said nothing about their period cranks being dangerous. >> >> Patrick Moore, who rides old aluminum cranks (and very old aluminum >> cranks! 8 sp Logic, 5 sp Pro 5 Vis, Viscount/Lambert -- the one with the >> tapered socket) and doesn't want to switch. >> > -- > You received this message because you are subscribed to the Google Groups > "RBW Owners Bunch" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/rbw-owners-bunch. > For more options, visit https://groups.google.com/d/optout. > -- Resumes, LinkedIn profiles, bios, and letters that get interviews. By-the-hour resume and LinkedIn coaching. Other professional writing services. http://www.resumespecialties.com/ Patrick Moore Alburquerque, New Mexico, Etats Unis d'Amerique ************************************************************************** ************** *Auditis an me ludit amabilis insania?* -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
