Hi, all, No tire that performs badly on a drum performs well in roll down testing. The inverse is not necessarily true. A drum test can point to a fast tire, but, because it doesn't account for losses in the sprung weight (that would mostly be the windbag pushing the pedals), cannot tell the whole tale.
For example, the second-fastest published roll down test run was a 27mm tubular. These do not typically perform that well on drums if glued with road (contact) glues due to the extra squirm, but they provide reduced suspension losses for the bag of meat sitting on the saddle in roll down tests relative to clinchers of similar construction. Mr. Heine correctly identified this deficiency in many "scientific" analyses of rolling resistance. They were only capturing tire casing hysteresis and not all the vibratory losses associated with a bicycle and rider rolling over a real-world surface. As long as you always sit down and spin, his conclusions seem to be well supported by riding. Stand up, or Sprint at speed, and there are significant factors not accounted for by a roll-down or a steady-state seated effort. Best Regards, Will William M deRosset Fort Collins CO USA -- 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 rbw-owners-bunch+unsubscr...@googlegroups.com. To post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at https://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
