Takahashi, That is an interesting comparison. Like you, I am surprised that our Barlow Pass tires weren't super-fast. At first, I thought about why this could be... until I realized that you did only one run with each tire. You mention that yours isn't a detailed study, and you are right. It would be erroneous to draw conclusions based on a single run, especially on a road course where so many variables can change.
It's very important to control all the variables when testing tires. For example, at Bicycle Quarterly, we test on a track, and only when there is no wind (measured with a windspeed meter, < 0.5 m/s; but looking at trees and checking that the leaves don't move is equally precise). We also measure temperature and correct for that based on a curve we've established by measuring the same tires at different temperatures. We do at least three repeats with each setup. On an open-road course, you'll have many more variables that change. The way to deal with this is to do repeat runs until the variations average out. A statistical analysis helps you figure out whether you've reached that point. (Bicycle Quarterly's tests always include a statistical analysis to make sure we report actual differences between tires, rather than just "noise" in the data.) So I encourage you to do more test runs with at least some of the tires, and then do a statistical analysis. If you need help with that, we can help. (BQ contributor Mark Vande Kamp has a Ph.D. with a minor in statistics.) In the mean time, rather than looking at numbers, it may be more useful to report your impressions of riding each tire. How did they feel different on each section of your course? Which one was more fun to ride? In the end, that is what counts for most of us when we ride. Again, thank you for doing the testing. Please continue the experiment until you get meaningful numbers. It's of great interest to all of us how these tires perform. Jan Heine Compass Bicycles www.compasscycle.com -- 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 http://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
