Eight point V bar. From the moment I bought my first set of high quality road clinchers, I’ve ridden at that pressure. I started with that number because that’s the pressure the sidewall told me to pump them up to; I didn’t yet understand much about balancing the benefits of high and low pressures to optimize comfort and friction; I just pumped them up as instructed and off I went merrily down the road.
I’m not as thin as I’d like to be, which is the same thing as saying I’m fatter than I should be, though I certainly hope I climb well for my weight, especially as my third (and hopefully charmed) ascent up Haleakala is looming large in Vajanuary. The point is, I’m not a whippet and even if I starved myself for the next five months and subsist exclusively on IPAs (I draw the line at cutting beer out of my theoretical diet; I might get desperate, but I’m no savage) I’d still be an Eros Poli at best. Being a big guy, the only factor that mattered to me when it came to tire pressure was avoiding the pinch flats that plagued me during my time riding cheaper tires and that meant maximum pressure, no questions asked.
We always dialed our pressure in for Mountain biking and would pull a few pounds out of our road tires when riding in the rain, but by and large, tire pressure was tire pressure, and as far as I was concerned, more was better. I even had a set of 20mm tires on a makeshift TT bike I had that I blew up to a whopping 10 bar. In the last few years, however, the Cycling world has become obsessed with doing the limbo and seeing how low they can go on tire pressure. It all began with an article in Bicycle Quarterly which conducted an extensive and flawed study on the effects of tire pressure and tire width, and concluded that lower pressure and wider tires are faster and more comfortable than high pressure, narrow tires; the idea is that lower pressure allows small bumps to be absorbed by the tire rather than bouncing the bicycle (and rider) in the air, and that wide tires flex more efficiently than narrow tires resulting in lower rolling resistance. Its important to remember that this gain in comfort and efficiency also comes with an increased risk of pinch flats.
This is all well and good, of course, though we always have to be careful to remember the basic principles of such a compromise; lower pressure and wider tires also mean an enlarged surface area which necessarily means more friction; a perfectly hard, narrow tire on a perfectly smooth surface would have almost zero friction, to the point that you’d be unable to gain enough traction to actually move the bicycle at all. What we’re after, in a practical sense, is a balance between the two extremes which optimizes comfort and tire efficiency against reduced surface area and the risk of pinch flats.
I became infected with Tire Pressure Fever myself as the Cycling world became increasingly obsessed with tire pressure. Down went the pressure in my tires and immediately I felt sluggish and lethargic on the bike. Climbing out of the saddle, I could feel the tires flex as I unleashed the Awesome Devastation of the Toothpicks of Navarone. Cornering was like steering in molasses; turn the bars, weight the pedals and then wait a few moments while the bike got round to responding.
These observations first had me reaching for the pump and then got me theorizing about what is really going on with tire pressure and what pressure is right for a given rider. I say “theorizing”, but most other people would use something closer to “guessing assertively”. But that doesn’t mean I’m wrong.
Basically, it comes down to finding the highest pressure and narrowest tire you can that gives a rider of your weight the right amount of tire flex such that your bike isn’t bouncing as it rolls over the tarmac and allows it to roll efficiently, all while minimizing surface area, risk of punctures, and sidewall deformation when accelerating (cornering and climbing are basically the same as accelerating; the acceleration vector is just in some other direction than forward.) This means that each rider at each weight with different preferences on the sliding scale between the above compromises will find a different optimal pressure. Impressed by Tom Boonen’s tire pressure at Roubaix? Tread carefully; that pressure was dialed in based on very specific criteria and unless you’re eating the same cobbles and weigh the same as he does, you’ll need a different pressure to find the same balance. Bicycle Quarterly has a chart that shows what they believe to be the ideal pressure by rider weight, though I don’t believe a word of it; I do however entertain the possibility that I could be missing something based on the fact that I didn’t actually read the article.
Me? I’m still happily riding at 8 point V. I’m comfortable, I’m not flatting, and I’ve got good control. Besides, it just has a nice ring to it.
I know as well as any of you that I've been checked out lately, kind…
Peter Sagan has undergone quite the transformation over the years; starting as a brash and…
The Women's road race has to be my favorite one-day road race after Paris-Roubaix and…
Holy fuckballs. I've never been this late ever on a VSP. I mean, I've missed…
This week we are currently in is the most boring week of the year. After…
I have memories of my life before Cycling, but as the years wear slowly on…
View Comments
@Nate
I agree wholeheartedly, and this is more or less the point I was getting at. The FMB's construction is so sublime that they perform amazingly at high and low pressures; even at 9 bar, they feel like pillows. The all weathers I'm riding on the rain are probably better to ride lower because their casing is so unforgiving that there's likely too much loss in the rolling efficiency.
This is, of course, a nonsense expression; less is less and more is more. Less might be better, but its not more.
I don't think it doesn't matter, I'm saying it has different forces on it than the back and therefor requires different thinking. Case of extreme is CX; I lost my front wheel in a fast corner because I was running it too low - the back tire needs traction to give grip for acceleration but the front only needs it for steering - they're very different requirements. You can run - and I have been doing this quite happily since my crash - the front much higher than the back and have great steering control while the back is run really low to keep good grip on the mud. This also keeps the front from flatting when you hit something hard; normally you hit something and bang the front rim and then instinctively unweight the back a bit - if you have the front high enough not to bang there is a good chance you'll be off the wheel by the time it hits the same thing.
If your front wheel needed zero traction, we'd all be on unicycles and, as @Chris says, then we'd be on a different site...
@Deakus
If that didn't work go to the sites Vittoria home page and check the TECH tab under that pick FAQ and then scroll down to what they refer to as the ideal tire pressure chart. While im sure someone put alot of time into creating it , there is no substitute for works well in our own neck of the woods. 8+bar "V" for me. 90kg fighting weight and happy. You said it best , lets just ride and look forword to the IPA at the end .
Unrelated: Wiggo jams out? He looks mighty uncomfortable.
I've found myself in a position where my only pump is a €14 handpump from Decathlon (a sports megastore here in France). I lack the necessary Velominatus Budgetatus savvy to acquire an actual pump, so I'm running my tyres at whatever pressure my forearms tyre out at.
My (cheap) track pump broke a while back, so I have been riding at about "I'm sick of this hand pump"bar for a couple months. Lots of flats, but a Lezyne is on the wish list. My rear has had a slow leak for 2 or 3 weeks and I was too lazy to patch it so I just inflated it everytime, it would be flat by the next day. I just patched it though as part of my Christmas break great bike strip-down and clean.
@VeloVita
Panaracer Pasela TG K 25c. No trust in me.
@frank
Was looking for a site containing monkeys on unicycles but found this excellent example of peer pressure going wrong:
@itburns
That is just awesome! Shame the monkey did not remove some of the daft idiots from the gene pool!
@unversio
I'm not sure what you're saying, but that tire at 320 grams probably rides a lot differently than the 220g Grand Bois Col de Madeline or Cerf I was referring to. I'm guessing the difference would be akin to sleeping on a rubber 'piss protector' sheet vs some 900 thread ct Egyptian cotton. That said, each serves its own purpose.
Not sure what I am saying either. You gave a wonderful analogy though. I'll go back to my silence.