BikeTechReview

hey, I just wanted to share an experience I had by using power.

Y'know all that tire pressure stuff I was doing a month or two ago???

Well, I figured I'd give what I learned from that exercise, i.e, that 140 psi tire pressure more than likely leads to lower rolling resistance for the conditions tested , a go "in the real world" and promptly set a PB time record on my local 20MP hill...all this despite having lower power and higher mass than I've had in the past.

an interesting takeaway, eh?! FWIW, I haven't had any real luck doing this sort of fine resolution testing using the WLB method of field testing by power when it comes to small aerodynamic changes...it just doesn't seem to work out, it seems...and I don't have much more patience after doing all those tire psi runs...what was that...probably hundreds of laps!?! yikes!

as an aside, the beauty of buying cheap ass tires in bulk (for me, anyways), is that at least the tires remain relatively the same over a span of a few years...so, I feel no shame in setting and claiming this PB up couser canyon road here in SoCal -y'know, it wasn't because I swapped out my tires/tubes or cheated and put on my race wheels!

...but alas, I'm on my last set of zaffiros, and will soon have to start some new pb's up couser once I find a suitable 20-23mm tire for less than $15 each delivered. Any leads?

I should be getting some panaracer stradius sports in at the end of the week, that just barely meet these criteria. I hope they aren't faster than my Zaffiro's!!!

Al, have you tested these?

kraig wrote:


Nope - but if they fit on your bike the Bontrager Sport 25 (measured ~ 24 mm) or the Bontrager Select 23, 25, 28 all roll very well. The Sport 23 was a real dog for some reason. The sport runs ~ $11 and the select ~ $16 last time I checked.

kraig wrote:


Tailwind?

I'm in favor of high pressures for hillclimbs also... vibration is less of an issue at low speeds and high pressure may reduce losses due to squirm.

Ron Ruff wrote:


I'd say the wind was typical. Somewhere on the forum, Dan scraped some of the data I posted WRT a regression I did for w/kg and time for a bunch of times up that climb -> not controlling for wind...I want to say off the top of my head, the W/Kg using just my stopwatch was +/- 2-3W...so, that's my long way of saying wind doesn't play much of a role up that climb, it seems.