Thread: Bicycle thread
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Old 10-24-2012, 07:16 AM   #25766
Beastly Adventurer
Joined: Feb 2009
Location: central IL
Oddometer: 3,321
Originally Posted by pierce View Post
he's got a point., a front blowout at speed is skeeery, especially in a turn. I left quite a bit of road rash on Laureles Grade near Carmel Valley once when my front sew-up ("tubular" to you kids) came unglued at speed.
Yeah, but, rolling a tubular off the rim is totally different than a blowout. In over 30 years of riding, I've never had a blowout. I'll continue to rotate my tires, to get the most out of my equipment, and leave the safety-nazi crap to the internet.

Originally Posted by brianwheelies View Post
Actually that was on the 25's I run now. Had two rears and a front go out.

I guess a smoother ride with less pressure may not be a bad thing. Less pressure means less tire inflations, right?

I am pumping up tires every two to three days. When the LBS sold me the bike he said to fill it to max psi and run for two weeks when it drops to 80psi and refill. Two days drops 16psi.
Well, the LBS is selling inaccurate advice. There's a good article here. I don't believe everything I read, but, I did try this one, while I was competing in time-trials. I definitely picked up speed and experienced a much smoother ride, when reducing pressures. There was noticably less slowing over chattery, chip and seal surfaces. Also, when you inflate to such high pressures, you're stretching the rubber of the tube. Bicycle tubes are naturally thin to reduce weight and rolling resistance. The more stretch, the more air that seeps through that membrane. And, you should be checking your tires, before every ride. You'll get better wear and more likely to find a tire problem, pre-ride.

My GF and I, both, run 32mm tires. I had a local, who's considered to be the "go-to guy" around here (he runs 23mm on everything, including his tandem), question our tire sizes and saying how they must feel really slow. When I explained that we ride whatever roads we feel like turning down and that we ride a lot of dirt and gravel, he shook his head and said "Not for me.". We broke his draft, when we took off.

What one has to realize is that there's going to be so many square inches of contact patch on the ground, based on the weight carried. In a narrow tire, that contact patch is going to be long and narrow. Conversely, a wider tire's patch is going to be shorter and wider. The narrower tire's longer patch flexes a longer portion of the sidewall, which decreases efficiency. Sidewalls are purposely made thin to allow for easier flex and better efficiency. Even so, there's a whole lot of rolling resistance in all that sidewall flex. I don't know at which point aero trumps sidewall flex in tire width, but, I'm not going to get that worried about it. For me, I'm fast enough, I go down whatever road looks intriguing, and I'm having a great time doing it. I'll leave the skinny-tired types to battle the traffic, on the asphalt.

BTW, I'm moving up to 37mm or 38mm, on the next set of tires. A bunch of new stuff just hit the market, so I'm still undecided.
'09 Triumph Tiger1050
'96 Ducati 900SS
'02 Suzuki SV650S (hers)
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