What was the time compared to smaller tires?

You should toss some 32mm on those babies. Of course this comes from a guy who 5 years ago was doing group rides on commuter bike with baskets, rear rack, and 42mm slow rolling commuter tires. I do think everyone would have a more enjoyable (and safer) experience if we stopped having an arms race and just rode more comfortable, albeit sometimes slower equipment.

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Just wait until you put a nice 32 on there, like the Hutchinson Sector, and ride em at 50 psi. 32s are the new 28s.

How much do you weigh and what pressure did you put in them? Real benefit to the large tires is really depressurizing them. I'm normally 165ish lbs and run 28mm at 60psi on enve's for training. Sooooooo smooth.

Not sure what you mean by 'thinner' tire here. The GP 5000s are a race-level tire with one of the lowest Crrs out there. The tread thickness is largely irrelevant, but typically thinner tread will have lower Crr.

The only way 28s become slower than narrower tires in terms of Crr (23mm or 25mm - which I believe is what you mean here) is by lowering the pressure down to 80psi or below. When the pressure is equalized between tires then 28mm tires are actually faster (lower Crr) than narrower (23, 25) tires.

FYI GP5000 28mm tires are equivalent to GP4000 25mm tires (and probably any other 25mm tire)

Not quite, they are just closer to their stated size than 4000s are. GP 5000 28s measures about 29mm on an Enve 7 wheel, whereas the GP 4000 25s measures 27.6mm on the same rim.

I found similar. GP4000 28s hardly gave me any clearance, but GP5000 28s give me loads! I reckon there is a good 2mm difference at least.

I'm usually in the 82-84kg range (180-185lb) and I ride 25mm GP4000 on narrow wheels (15mm I think) at 80-85psi front, 90-95psi rear. On my wider rimmed Swiss Side Hadrons (19mm internal) I use the same tyres at about 75psi front and 80-85psi rear. I've done so for about 3 years now and have never had a pinch puncture. 25mm GP4000 may be a bit oversized but nevertheless 90psi on 28mm tyres is unnecessarily high.

Yes I've found the same to be true. GP 4000 28s measure almost 31mm mounted, whereas the 5000 28s are about 29mm. I can run the 5000 28s in my QR PR6 on Enve wheels, no way with the 4000 28s.

I'm not sure exactly how much taller they measure, but wider typically means taller as well.

THANK YOU for sharing, I've been trying to figure out if I'd be able to stuff a 28mm 5k on my PR3. I'm assuming rim brake? Is it tight or...?

Rim Brake. You'll need to use the horizontal dropout on the rear in order to get enough rear tire clearance (vertical is too close), but I would say its not even that tight. I've got a few mm clearance both front and rear on the PR6 with GP 5000 28s.

I run tires measuring a full 33 on my Madone SLR. My teammate rides and races gravel with his. He runs a 35 front / 33 rear.

For me the GP4000 in 28 measured 33. GP5000 in 32 measures 32. I'm not sure these huge tires don't give up a fuzz bit of speed, but if they do it's not much. I've ridden mine in the 50 and less PSI range at 145#. No problems at all.

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If running 32/33 on gravel 30 to 35 psi is ideal for me at about 155 when kitted up and 2 bottles on bike. Of course this is tubeless but it really does make it easier rolling over fresh aggregate.

Before I got my gravel bike, I put a set of 28mm Kenda Karvs on my road bike to do a couple of mixed-surface rides and was very pleasantly surprised at how well they rolled on the road portions, and it was noticeably smoother too. Left them on for a 100% road ride (winter, so I figured they'd be good for potholes, debris etc) with some training buddies and was able to keep up with them without any problems.

28 is the old 25 which was the new 23. It is all pressure and size. I have noticed more and more bikes are fitting 28s than they were 5 years ago.

Be careful. Once you start going bigger it is a slippery slope. I went to 38s and then 42s and now I really love running the 47mm WTB Byway up front and the 50mm G-One Speed on the rear. I can pretty much ride any terrain on those tires and don't feel slower on the road. I'm not a crazy corner shredder so I can go as fast as I want offroad and the tire volume eats up bumps and road imperfections. I think Conti acknowledged the desire to go bigger with their 32mm tire and it won't be long IMO before they start making larger and larger tires with those casings. In my experience, there is no downside.

While everybody is bragging about how wide their tires are, I think they are forgetting to mention how much lower you can (and should) be running the pressure. I have 10 lbs on you and rode those 28's in the 50-60 psi range on pavement since they measured ~ 31 mm on my rims. I ran them in the 40's for rides that saw some mixed surfaces. No 'gravel' since I don't trust the thin sidewalls.

The general consensus it that the lower pressures result in a faster setup. The tire under lower pressure can deform more than one at a higher pressure, thus it 'rolls' over bumps/cracks instead of 'bouncing' over them. The rolling results in less energy loss than the bouncing, thus a faster setup. At least that's my understanding

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the world's still turning? >>>>>>> the world's still turning

I can't tell you how you felt they rode. To me, it would feel too hard. They do grip better at lower pressures. *Hopefully* they beat you up less on long rides. If we take guesses about rolling resistance out of the equation, better grip braking and turning is about the only for-sure thing.

It's not worth much, but I tried chung testing to tease out difference in rolling resistance in real-world riding with my race tires a couple of years ago. They were 23 front 25 rear being ridden in a nice paved loop in a newer construction neighborhood. I didn't test lower than 85, but 85 was the fastest for me based on that single test of a,b,c,d,d,c,b,a.

If you're mostly riding on decent pavement, there's going to be a big range that works well. If you want to geek out more, check out Flo Cycling's Blog entries from 2014 or just about anything from Silca. They have one where the 'summary' section speaks pretty specifically to this conversation.