Over the years, Rivendell has trimmed its offering of larger sizes, independent of tire size. They don't offer anything equivalent to the Redwood, which went to 68, and have stopped offering the Atlantis in even a 64. I don't own an Atlantis but if it came in a 64, I would be tempted.
michael On Aug 15, 1:29 pm, RoadieRyan <rya...@hotmail.com> wrote: > Is it possible the "retreat" from larger sized 650b is simply a > business decision? I get the impression, no hard facts, that there is > less demand for larger sizes, especially over say 62 cm, than the mid- > range, so it would follow that demand larger sizes spec'd for a "non > traditional" wheel size is pretty niche. > > With a tough economy, constraints on manpower and financial resources > it would make sense to me that Rivendell would build to meet the > greatest demand in order to maximize sales and revenue. Not that the > bottom-line drives their business but it is a big consideration. And > for those folks who really want a larger size designed around 650b > there is always a Riv custom, so its not like they are left with no > options. > > just my uninformed 2 cents > > Ryan > > On Aug 15, 6:47 am, MichaelH <mhech...@gmail.com> wrote: > > > I think this is right. I don't think Grant has "retreated" from 650B > > for larger sizes. He has always argued in favor of wider road tires, > > 28-35 mm, and that it is easier to achieve that on small frames with a > > 584 rim diameter because the 622 size forces unwanted compromises on > > the frame design. This isn't true in larger sizes, as shown by the > > AHH, my Ebisu and SOMA dbl. cross. > > > I have never felt the need for anything larger than 38 on dirt or > > even gravel roads However, it is also true that smaller rims are > > stronger. Our road tandem runs on 559 rims with 1.6 Marathon Racers > > and carries 380 lbs over dirt roads with remarkable strength and > > comfort. If you are riding trails, than you are essentially talking > > mountain bike design for tires that are bigger yet. Grant's focus has > > traditionally been road bikes that handle trails as well, only > > recently has he offered a "pure" mountain bike. > > > michael > > > On Aug 15, 2:01 am, Bill Gibson <bill.bgib...@gmail.com> wrote: > > > > I always thought of 584/650B as a way to get more tire in the right > > > frame size with all the right clearances for fenders, etc. more than > > > any other reason. And that especially for smaller sizes that even > > > smaller wheels - 559/mountain bike size or - in my wife's case, for > > > her mountain bike, 507/24" (she is 4' 10"), are required for > > > stand-over heights, etc. Seeking optimums in moments of inertia, > > > various hysterises (is that a word? what is the plural of hysteresis? > > > hysterii?), aerodynamic resistance, rolling resistance, pneumatic > > > trail, contact patch shape, and so on has to be a matter of...personal > > > taste and much further research? Maybe matching to load and road > > > surface, too... > > > > Amazing how little changes have such strong real or placebo effects... > > > > On Sat, Aug 14, 2010 at 9:16 PM, PATRICK MOORE <bertin...@gmail.com> > > > wrote: > > > > Rob Perks wrote: > > > > >> The volume of air that affects rolling resistance is the cross section > > > >> of air directly above the area of deformation. Therefore it stands to > > > >> reason that wheel diameter should not play into that. > > > > > It is, so they say -- I am not an engineer -- the contact patch (a > > > > sign of > > > > which is that tire suppleness affects rolling resistance greatly, > > > > indicating > > > > that it is the contact patch and not just air volume) that, all else > > > > equal, > > > > determines rolling resistance, and that is certainly affected by wheel > > > > diameter. > > > > Snip. > > > >>WRT to smaller wheels and faster acceleration, I have ridden 26" - 29" > > > >>with all sorts of tires and still feel that the greates factor > > > >>affecting acceleration is the weight not as much the diameter. e. > > > > Not quite, I think. First, it is indeed the smaller size that makes > > > > smaller > > > > wheels so light. You save 100 grams or so at the circumference on the > > > > rim > > > > and 50 more on the tire, ceteris paribus -- my Sun M14A 559s weigh 360 > > > > gr > > > > (and are strong enough that I had no problems at all off road) and the > > > > 559 > > > > Turbos and Conti GPs weigh just under 200 gr. And then add the > > > > cumulative > > > > effect of taking a bit over an inch off each spoke. My old > > > > Ultegra/nothing > > > > special 8-9 sp 559 wheelset weighed about 1500 grams with rim tape, no > > > > skewers or cassette. > > > > Second, most of that weight is at the circumference and we all remember > > > > the > > > > Law of Moments. > > > > Again, riding fixed, you can certainly feel the difference. > > > > > -- > > > > 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-bu...@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. > > > > -- > > > Bill Gibson > > > Tempe, Arizona, USA -- 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-bu...@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.
