I've got some 25mm PR3's. On my 23mm wide A23 rims, the PR3 is 27.4mm wide, and on my Kinlin XR250 (19mm wide), the PR3 is 26.1mm wide. Michelin seems to be pretty honest about tire width. That's much better than the manufacturers that try to win the weight game by making a tire narrower than its stated spec just so they can save a small handful of grams. I'll gladly take a tire that is a little wider than its stated spec.
Yup. Finding the Higgs Boson is a lot easier than cracking that flat mystery. The only time I can reliably predict flats is during the monsoon here (and then I only know the flat rate is likely to go up), when all the trash, sharp rocks, goatheads, cactus needles, and other pointy things get washed out onto the pavement. About 4-5 years ago, right in the middle of the monsoon season, I had a 2 week period during which I had 10 flats: 4 on tubulars, and 6 on clinchers. Oddly enough, I developed a pretty damned surly attitude--as well as sore thumbs from stitching repaired tubies back together--during that period.
In Tour's defense, they do a pretty spiffy job of testing bits. They definitely are a technically oriented magazine. Their tire test was pretty good, although the worthiness of their cornering rig is questionable. I don't think there is any bias towards Conti in their testing. Likewise, I don't think there's any bias toward a given company in Bicycling's efforts to "test." I do think Bicycling displays a significant lack of creativity or, in the case of bikes chosen to test, a lack of motivation to test anything that isn't from their common, small pool of the same 5 - 7 brands they always test. Still, Bicycling is not meant as a technical rag. With the exception of a few stories, BikeSnob, and the Bob Mionske bits, Bicycling is pretty much the Reader's Digest of bike rags. It is perfectly suitable for toilet reading, unless you have really bad constipation, in which case you just might finish an issue well before finishing your peristaltic exercise.
1. Not a problem.
According to the AFM test I have in front of me, they measured the GP4000s' Crr to be 0.00284, not 0.00384. That is a very good Crr. It's very close to the Crr of a 21mm Vittoria Corsa EVO CX tubular, which is 0.00275.
You could very well notice the difference between the Conti GP4000s and, say a Conti GP3000, the worst tires in AFM's test. It's impossible to say what will matter to a rider or not. You shouldn't confuse what matters to you with what matters to another rider. Note that someone being a recreational rider doesn't necessarily mean that person just likes to putter around. They might, for example, enjoy getting all the speed they can. Speed and maximizing it isn't just something of interest to racers.
That's completely false. The equations that model aerodynamic forces on bikes--or anything for that matter--do not include step functions. They do not just turn on at some magical speed. There is absolutely a reduction in drag with deeper rims. It doesn't matter if those deeper rims are only 30mm deep. Perhaps the aero benefits aren't as large as a rider believes or as a marketing person has led someone to believe, but the benefits are still there. Similar to above, whether the benefits are acceptable or not is entirely up to the rider.
Well, you're always free to do a test that shows that riders will not notice a difference. Belief, however is neither proof nor is something worth debating. For many riders, choosing clincher is the sensible choice, the only choice, or one of several other types of choices. The Conti was 51 out of 112. Tires. Make sure to note that some of those tires that had lower Crr than the GP4000 were tubulars, time trial tires("chrono" or "light"). If you analyze data, you have to take such considerations into mind. Those factors are relevant, especially as it's not every rider that rides tubulars or time trial tires. Also, there are a number of tires in that test that aren't even available any more. Certainly, Crr is not insignificant. It's also not so small that it's out of the realm of possibility that someone could tell the difference between a "fast" and a "slow" tire, especially out on the road where, according to AFM, Crr can be on the order of 50% more than their lab derived values. I know I could damn well tell a difference between Tufo S33's and Vittoria Evo Corsa CX's--in how they rode (which encompasses several factors) at the same pressure, just as there was a difference between the Tufo's and even Conti Sprinter Gatorskins at the same pressure.....and the difference in each case wasn't in Tufo's favor.
I agree, thanks for saying that, someone needed to.
I think a road surface could be simulated with a textured drum, but it might not be worth it. Using an iBike power meter, you can back out a rolling resistance value, but it takes a little bit of work. Also, the iBike power meter is very sensitive to setup.
I've seen those Maxxis Re-Fuse tires on sale every now and again for below $30 and they get high reviews though most of the reviewers said they felt dead and sluggish, any thoughts on that? Thought about trying them out but haven't yet, thanks for the thoughts on those; next time I need a set of tires I'll try those. How many miles do you get on a set of these?
