Hi Harvey,,,,,post was meant to simply counter my previous negative post on the harsh ride of the Raysport with its other wheelset (included tires as part of the term wheelset --- most definitely technically incorrect). The previous wheels were Campy Record large flange laced 3-cross to Fiamme Ergal rims (15 gauge spokes). The "softer" feeling wheels are Campy Tipo large flange laced 4-cross to AVA rims (front wheel uses "double-butted" 14-15 gauge spokes). In my opinion and experience, 4-cross spoke patterns always yielded a softer feel. The tire width I switched to wasn't that much of a difference (i.e., approx. 21 to a 23), but you are absolutely right that the tires (slight width increase and quality level) probably had more to do with the softer ride than the wheels (rims). I have a few sets of wheels, with a range of rim widths. Found the old AVA (like some Mavics), appear to have been designed specifically for a wider tire. Wonder if a wider tire on a narrow rim has the same characteristics as when it is mounted on a wider one??? Are all metal rims created equal??? Know of any studies done on this??? Oh well,,,,,wasn't trying to be scientific with my post, but just happy to report a much nicer ride on the Raysport. Sure that if I could afford a batch of Dugast's that I would be riding on heavenly air on each and every one of my rides. I, and I am sure you too, enjoy actually riding more than pondering the science of it, but appreciate how so many like to dig really deep into the nitty gritty of it. Thanks for your feedback on my post. Kindest regards, Kevin Kruger - Grantville, PA
Harvey M Sachs <firstname.lastname@example.org> wrote: Kevin Kruger's post puzzles me:
"As a result of my recent 1976 Masi GC build, I swapped some wheels around on my various bikes. One switch involved my Raysport, with Campy Tipo large flange hubs laced to fairly wide AVA tubular rims along with slightly wider tires (NOS "Criterium Sprint" tires).
Well I was pleased to find that these wheels softened up the harsher ride this short wheelbase/straight fork bike to provide quite a very comfortable ride!!!
Certain that a set of small flange hubs would change the ride ever more.
While the Raysport ranked low on my list of ride comfort before,,,,,,I really have changed my opinion with the different wheelset, and truly enjoyed the 40 miler just completed on it!!!" ++++++++++++++++++++++++ What I don't understand, Kevin, is why you attribute the difference to the wheels rather than the tires. The wheels are all-metal, and fairly well stressed, with low "compliance." On the other hand, you note that you installed slightly wider tires, which are basically just thick-walled balloons: flexible rubber held roughly in place by modest amounts of highly-comressable rubber. They compress and rebound as the contact patch moves around the tire any time the wheel is moving. The analyses I've seen - but don't claim to follow completely - would strongly implicate tires and tire pressure differences as a completely adequate explanation for what you felt. Anecdotally, I once has a Raleigh International, with the best available (27x1-1/4) tires and rims. Felt sluggish, so I sold it to a friend. He put sew-ups on, and it rode transformed, in my opinion.
So, you could be right - a measurement beats a theory any day - but wouldn't it be nice if someone expanded on the Chemnitz work, or whatever, and gave us some more complete empirical testing?
harvey sachs mcLean va
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