On thought about rim temperature...if the temperature is going to weaken the metal...it's going to more than feel hot on our fingers...it's going to sear them. The rubber bits will melt first.
Angus On Dec 7, 1:10 pm, Ray Shine <r.sh...@sbcglobal.net> wrote: > I'm with you! Scary, especially since I ride soooo many hills and grades. > Lots > of braking. > > ________________________________ > From: Sean Whelan <strummer_...@yahoo.com> > To: rbw-owners-bunch@googlegroups.com > Sent: Wed, December 7, 2011 10:35:17 AM > Subject: Re: [RBW] Re: Near-Catastrophic Rim Failure > > All of this talk has me suddenly worrying about what my many-year old rims > with > thousands of miles on them would look like in profile when hack-sawed. > > I think this thread might jump start the Christmas Wheelset sales rush. > > I, for one, am thinking about it rather seriously. > > Thanks, > Sean > > --- On Tue, 12/6/11, Grant Petersen <gep71...@gmail.com> wrote: > > > > > > > From: Grant Petersen <gep71...@gmail.com> > > Subject: [RBW] Re: Near-Catastrophic Rim Failure > > To: "RBW Owners Bunch" <rbw-owners-bunch@googlegroups.com> > > Date: Tuesday, December 6, 2011, 2:08 AM > > Many of you will remember, and all of > > you can relate to Keith > > Bontrager's maxim from the late '80s: > > > Light Strong Inexpensive: Pick Two > > > It works to some extent with all bike parts, but even IT > > can't come to > > the rescue when the thing is just too light. > > > Do you know the thickness of the braking surface on a > > typical road > > rim? It's about 1.2mm. Some are 1.1. That's what fails when > > rims wear > > out and blow out. Well...1.1 or 1.2mm looks like nothing, > > which you > > consider the abrasion they're subject to and can't possibly > > avoid. > > (Disc brakes have their own set of problems, so let's stay > > on track.) > > > It used to be common practice to inspect brake pads AND > > rims, but > > raise you hand if you can remember the last time you did > > that. > > > How much should a non-racing 700c rim weigh? How thick > > should the > > braking surface be, and how tall? How wide should it be? > > Reasonable answers, kind of, could be: Weight: 500g. > > Thickness of > > braking surface: 2.5mm. Height: 11mm. Width: 24mm. > > But a rim with those specs would weigh about 800g. I > > believe this > > because we're having a NOBS rim made to our specs, and it > > has 1.6mm > > braking surface, 10.5mm brake surface height, is 25.4 (1) > > mm wide, and > > weighs about 650g. It's wider than 24, but way thinner than > > 2.5, and > > the 10.5<11. I think this is a totally reasonable rim, > > in every way. I > > wanted 2mm of braking surface, but that would have meant > > zero buyers, > > so we settled on the world-record 1.6, bringing the weight > > down to a > > near world record 650g, and even though I think it's a > > perfectly > > fantastic rim for general nonracing use---touring, trails, > > commuting, > > all purpose riding when there's not a timer or a finish > > line with a > > banner---I believe we'll end up selling it mostly to guys > > who weigh > > 300 pounds and are sick and tired of wheel > > problems...because most > > riders like the idea of stout stuff, but don't really want > > the weight > > that comes with it. > > We'll continue to offer other rims....but this new rim will > > be the way > > to go when you truly, really, want a durable rim and > > wheel. > > (Anyway....the new stouty won't be available for many > > months). > > > -- > > You received this message because you are subscribed to the > > Google Groups "RBW Owners Bunch" group. > > To post to this group, send email to rbw-owners-bunch@googlegroups.com. > > To unsubscribe from this group, send email to > > rbw-owners-bunch+unsubscr...@googlegroups.com. > > For more options, visit this group at > >http://groups.google.com/group/rbw-owners-bunch?hl=en. > > -- > You received this message because you are subscribed to the Google Groups "RBW > Owners Bunch" group. > To post to this group, send email to rbw-owners-bunch@googlegroups.com. > To unsubscribe from this group, send email to > rbw-owners-bunch+unsubscr...@googlegroups.com. > For more options, visit this group > athttp://groups.google.com/group/rbw-owners-bunch?hl=en.- Hide quoted text - > > - Show quoted text - -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To post to this group, send email to rbw-owners-bunch@googlegroups.com. To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.
