Not simply a matter of momentum, nor personal preferences. The amount of pressure will dictate both the size of the contact patch and how elastic a deformation is, both of which affect how the tire will respond to surface irregularities.

Love it...

So now here is the second thought. If you make your ride in a loop and return to the same point how much of your ride is either up or down hill?

Elevation gain/loss will be same, but a early short 25%section and a long gradual downhill I suspect would be faster going down the gradual. Time wise for the loop I mean. I dunno..

If there are no apexes in this story then it's no fun, so there.

I'm sure tire choice would make a difference as well

Depends on Crr.

The good thing about being a product of the West Virginia school system is I don't understand a word of this. I can't get upset or argue with anyone.

i've found that cornering on a descent with a Sears & Roebuck wheelbarrow full of horse manure works best when running about 15PSI in the tire.

If it was pig poop, would you, could you, corner faster?

I have an orange bike....it goes down faster. That's a proven fact.

Just a few weeks ago I had to do my Saturday morning ride alone, because my usual friends were busy doing yard work, and when I got to the top of one of my favorite hills (used to be able to call them climbs before San Francisco) and a ...big... guy had arrived at the top some time before. We both started descending together and I had to put my face in my stem bolts peddling at 100 cadence to keep up with him riding down with elbows locked on the tops looking around casually. He had stock alu wheels and I was sporting by Boyd 60s. My jersey fits nicely and his was on its way to a parachute.

I don't need equations to tell me that weight on the descent makes a substantial difference.

that has happened to me so many times, face in the bolts, elbows in, everything and still spinning away just to keep up with guys just coasting.......but then on climbs heavier folks are sweating buckets and I can talk on the way up, so its a ying yang thing.

This made me laugh, as CRR are my son's initials. It made me wonder what he was tampering with now.

Yeah, I dig the karma of the uphill. Sometimes though, I end up next to Very large guys at 50+ miles of riding and I am somehow only then passing them on the 4th big climb

This thread is really going downhill.

Bicycle Quarterly did wind tunnel tests and at 22 mph going to full aero tuck with no pedaling and the knees tucked into the top tube created a 7 % reduction in drag coefficient. Meaning if your downhill will take you above 22 on coasting alone than don't waste a lot of time and energy spinning a high gear; get small and let mother earth pull you in.

This is so wrong it makes my head hurt.

Neither right nor wrong, just a perspective.

FWIW reducing wind drag by 7% at 22mph is worth about 1 more mph. Someone who can turn his cranks effectively should be able to do better than that. (if he wants)

More like .5 mph, or the equivalent of about 17 extra watts at that speed so I can understand where Rchung is coming from.

Time trialing and optimizing power, it might be a waste to push your speed downhill. But that would imply that you're time trialing with a 22mph top end ...

Seems like a full tuck would be worth more than 7% drag.