Back in the mid '90s, I had a customer who rode a Kestrel KM40. 650c x 23mm tires would rub on the underside of the fork crown…
Too bad you can’t run the goldilocks tire on the wheels we’re debating here…
New video:
Here’s the LinkedIn post/comments that were referenced: Hookless rims and heat: a safety concern for cyclists | Peter Appleton posted on the topic | LinkedIn
It’s interesting to see some of the comments and the companies those are tied to.
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It would be good to run a popular tire not on their preferred list.
Like a Conti 5000 TT
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What are you testing? blowoff pressures?
Is that a $6.00 Zoro pressure gauge?
You denied any help in the process remember …. So you can stay in the corner on this one 
18 thousand views in one day - you have to love it!!
Sounds like a “yes”.
a kind rider-by stopped to help me on one of my recent rides, he too was laughing at my 25s… I said, but these are my wide tires. he said, times have changed…
still racing on tubular 22s, that Cervelo Dual frame won’t fit even 25s. Not up for spending lots of money on a new bike to race old man slow speeds…
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It’s like crossing the streams! Stop man! You’ll kill us all!
thank you for the paper, had not seen any previous attempts to quantify the losses from rough roads.
There was a 48 watt decrease in power required between 90 psi (6.12 bar) and 30 psi (2.04 bar). While this graph indicates that tire pressures at or below 30psi (2.04bar) with a 28mm tire are the most efficient over a surface of equivalent roughness, other factors such as tire, wheel, and handling integrity limit the feasibility of using such low pressures. The data is from our RollingRoad™ testing and captures power losses from rolling resistance, vibration loss, and drivetrain while traveling 32kph over a simulated poor-condition asphalt (green line in the dynamic response plot of Figure 4 above).
that is a much bigger number than I was expecting…
I wish it was only $6 bucks
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Hey, that’s not six bucks !!
It’s 6.49 !!
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Hey, we’re cool with 7.6% error, right?
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Silca also published some data here:
Fascinating info.
More interesting is that, if one is using 25mm tires and riding average (i.e., not super smooth) asphalt, it appears that the break point for the lowest possible rolling resistance is still around 100 psi, or just over.
Remember that the test is 10+ years old on older narrower wheels (zipp 404 firecrest). I believe those were 16 mm internal width wheels. On today’s modern wheels (wider), the breakpoint pressure would be lower on a 25mm tire.
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