The skies at 3:18 am had been clear and gorgeous, star-lit and mysterious - the one benefit of the little dog’s recent & repeated recent need to go outside at that horrific hour. But, four hours later a tight and damp fog hugged the region and visibility barely stretched across the street. Not quite enough to dampen the ground, but certainly holding enough chill to mandate a second strong cup of hot coffee before heading out. Besides, nothing short of horizontal sleet was going to derail my first ride in over two weeks.
Hilsen got the nod because gear choice and coastability would be kinder. Pulling it down from the hook, I noticed the Jack Brown tires needed air. They easily compressed under strong thumb pressure. Normally, I would’ve whisked out the floor pump and brought them back into the “normal” range, but today that didn’t seem like the right thing to do.
Normally, I’m haunted by pinch flats - if not the actual occurence, then the avoidance of them. Riding 30-35mm tires on the exposed rock edges on the local trails is a good way to gank rims and get really good at quick flat fixes. So, I’ve evolved what is mostly an avoidance technique, I’ll admit it - I run tires pretty danged firm. Afterall, no one is going to mistake me for a bird-boned climber, and I’d rather get bounced around a bit more than pull the wheel, strip the tire, peel the tube and replace things.
However, one of the reasons that the Hilsen has such stantial frame clearance is so that you can run large volume tires. One of the reasons you run large volume tires is to enjoy the cush. Enjoying the cush means y’gotta let the air out. Which, as I’ve mentioned, I don’t tend to do.
And there I stood, pushing down on the bars and watching the footprint of the front tire spread out on the kitchen floor. Since this wasn’t going to be an overly technical ride, it might be a nice distraction to see how low things could go. Off I went.
The ride was cushy-smooth, giving more credence to the saying “33.3 is the new 650B!” The only thing I noticed was that the front ended felt a little sluggish while maneuvering at a dead-stop (as it well should, since the tire seem to have about as much footprint as my, um, foot…), and there was a pang of “We’re capsizin’ cap’n!” when I leaned over at said slow speed and felt the bike go deep into the travel of the tire. Seemed more that it acted “different” than anything actually dangerous.
The other slightly different behavior took place while descending a curvy stretch of road. I noticed that the handlebars now wanted to “turn into” the turn. Now, since bikes aren’t actually turned by “turning in”, it’s more likely that it was resisting my unconcious efforts to countersteer. And just to be doubly clear on this point, the bicycle tracked phenomenally well through the turns. There was not a corner where anything felt sketchy or were I had to push it harder to make the curve. It just had a little bit of resistance. More than likely, I was experiencing a bit of “pneumatic trail”, as Jan over at BQ uses it, sort of the rubber-meets-road equivilent of using really long skis.
By the end of the ride (in which my calf remained happy, thank you very much…), I was used to it - aiming the tires at anything resembling corrupted topography and relaxing more through the turns. Though the tires were softer than I will end up running them, it was instructive to see just how far things could be reduced (and I had the feeling that there was still a bit more I could have let out).
Big soft cushy tires. Who’da figgered?
October 15th, 2007 at 9:54 am Okay, what’s cushy to you? Could you put a gauge on that cush so that we can compare? I regularly run my 71 Raleigh International (set up very Hilsen-like) with Pasela TG 35mm tires at 45psi, sometimes as low as 40 and never above 60. On my new Quickbeam (Yay!) with Jack Brown Blues, I’ve been running them at 50psi and have been quite happy right there (mostly road so far though)
October 15th, 2007 at 12:56 pm So what do you think the “actual” pressure was in the JB’s? I ride my pasela TG’s (35s) as low as 40psi on my Atlantis and it feels like heaven has just laid down glass smooth asphalt for me as I glide over obstructions. Glad your likin’ the AHH!
October 15th, 2007 at 3:41 pm congrats on getting back on the bike!
October 15th, 2007 at 9:45 pm Ok - as soon as I posted this and ran out the door to work (ridin’ the Dawes), it struck me that I should’ve gotten actual, y’know, helpful data…
So, tonight I attached my floor pump to the tires and it revealed:
Rear Tire - ~26psi
Front Tire - ~24psi
Like I said, “squishy”.
In the few rides so far, I’ve been running the JB’s at around 50-60, maybe a tad more. As a comparison, I’ll run similarly sized Michelin Mud2 CX tires near 80 for sharp rocky trails.
And thanks JimG! It felt great to be back on the bike!
October 15th, 2007 at 10:46 pm Like you, I tend to NOT deflate my tires when the terrain changes. Instead, I fill them almost full and back off a tiny bit from that. (I never use a gauge…) This method seems to give me the msot comfort for the buck. Glad to hear you’re back on the bike. Hooray!
October 16th, 2007 at 6:43 pm Sweet, ain’t it? And yet, I too rarely avail myself of low pressure possibilities. My 1.75″ (that’s 45-ish mm, folks!) Panaracer T-Servs are usually between 40 and 60 PSI, and they only get down to 40 because I’m lazy about filling them. And what’s more, I AM a bird-boned climber, or I would be if my life were not too sucked dry by other things to find time to ride. I’ll probably let ‘em drop nice and low when winter gets here and we get snow and slippery stuff on the road. 20 psi ought to do me just fine. Low pressure gets the rubber on the road!
October 18th, 2007 at 1:14 pm Hi, Jim–glad to hear the leg’s OK and you’re getting out again.