icantaffordcycling wrote: ↑
Thu Sep 05, 2019 9:24 pm
CrankAddictsRich wrote: ↑
Thu Sep 05, 2019 8:15 pm
I am by no means suggesting racing on 19's, but with 30's, you've gone way too far in the other direction. I've done my fair share of racing, but for sure, I'm always learning and observing, paying attention to what the fastest people do and I've never seen anyone fast on 30's. Comfortable, yes... but fastest, no.
I could site a podium picture with the caption "30c tires were the right choice" or link 4 road races on the calendar with unpaved/gravel sections. You don't cite numbers or facts, just that 25mm tires feel fast and are the current choice of racers. I will be choosing 28c tires for most crits and road races with 30c tires for some races next year, as I said before, you don't know the roads I race on.
They are the fastest option for certain races, you are welcome to disagree but you would be wrong.
Edit: Grammar for dudemanppl
Edit 2: Spelling for tonytourist
I'm not saying bigger tires are never the answer.. sometimes they are. When I raced Battenkill I stuffed 27c Vittoria Open Paves onto my bike and would have gone bigger if I thought they'd safely fit. There are definitely some races that those 28's or 30's are the right choice, but in my experience, those races are infrequent. There's some information that says that larger tires are beneficial for decreased rolling resistance, which in theory equals more speed, but my research shows that those gains are most often offset by decreases in aerodynamic efficiency because of the wider tire and the interaction between the tire and rim width. If you tire is wider than your rim, resulting in a light bulb cross section, then you're giving up a fair bit in aero. The optimum tire/wheels width is usually one where the width of the wheels is 105% of your tire width... If you want to run 28's then optimally, you should be running a wheel that is 29.4mm in width. More often than not, the slight increase of rolling resistance from a smaller tire can be offset by better, more supple tires. The tires you're talking about using, though are all pretty good for racing purposes. If you're looking for specifics, check out the podcast from Josh Portner of Silca (former aero engineer with Zipp), I beleive he's the one that developed the 105% rule
. If not, he's the first one that I heard mention it. You can also check out Hambini's latest video on aero.
The other thing to be aware of is that bigger tires weigh more and they can be more difficult to accelerate, so if you're riding routes that involve slow corners that you have to accelerate away from or if you're climbing a lot, then larger tires will be slower. and mroe difficult to accelerate.