I'm fitting a clincher tire that's usually 2-4mm wider than the original tire. It's usually the largest tire that will fit with reasonable chainstay clearance.

I had a Miyata 615 and used 700x32 with good results. I'd recommend a 28 or 32.

1971 Peugeot PX10: 28x23 originally, 700x32 Compass Stampede Pass currently, measure 31.5mm wide

1972 Schwinn Paramount: 28x23 originally, 700x28 Vittoria Corsa currently, measure 28mm wide

1977 Motobecane Grand Record: 27x1 1/8 originally, 700x28 Panaracer Gravelking currently, 28mm wide

1984 De Rosa Professional: 28x23 originally, 700x25 Vittoria Corsa currently, measure 27mm wide

1985 Serotta Nova Special X: 700x23 originally, 700x27 Vittoria Pave currently, measure 27mm wide

1986 Eddy Merckx Corsa Extra: 28x23 originally, 700x25 Vittoria Pave currently, measure 26mm wide

1995ish Pinarello Gavia: 700x23 originally, 700x25 Vittoria Rubino Pro currently, measure 25.5mm wide

1995ish Simoncini Cyclocross Special: 700x28 originally, 700x27 Challenge Parigi-Roubaix currently, these measure 30mm wide

I most often ride 700x28 on my road bike. I find it a good compromise. They do well on the rougher roads I often ride on, and can handle occasional gravel riding. (if it isn't too loose) Sometimes I'll ride 700x25 Conti GP4000's, though in reality they measure 28mm mounted on A23 rims. I actually toured a bit on 700x28 Fairweathers this summer, including some gravel roads. Sometimes you just want to get to where the gravel road goes...

Then again 32 would be good for that bike. It was designed for that size. It used to be that if you went up from 28 to 32+ widths, tires got really sluggish feeling. It wasn't because of the width, it's because manufacturers figured if you wanted 32, you wanted heavy duty, not fast. With the light fat tires available nowadays, I don't know that you'd pay much of a fun penalty if going with a 32c or 35c if you got one of these nice modern tires.

I have a pair of bikes running 28-622 Schwalbe Delta Cruiser gumwalls and my daily city bike is running 42-622 Marathon Surpreme tyres.

I could probably easily run 37mm tyres on both the other bikes. Maybe I should try one of the faster models like the G-One once I have worn down the Delta Cruisers. But at €11 a piece they are hard to beat and look nice on older bikes.

I have two 25s (Pasela PT and GP4000IIS) and two 28s (Pasela and Corsa G+). I had some 32 Pasela PTs but they just seemed large and slow so I replaced them with 28s. Have ridden those tires before but haven't ridden that bike with them as of yet.

Start with 28's- good, supple ones- at low-ish pressure and see how they work on your local version of chipseal. Around here, 25's are fine on chipseal but out in farm country the raods may not be as smooth to begin with.

Pretty much everything in the stable wears 25's with the exception of a new yet-to-be-shown all day rider that's wearing Continental 28's. And Schwinderella, which has Compass 650b 42's.

Ride 700 X 25's and 650 X 42's back to back and you'll discover how much slower the 650b's are. Cushy cushy and a lovely ride, but slower to accelerate, at least in my experience.

+1

Well, I think I want a bit more clearance than 1-2mm, 4mm min to keep me from worrying. I tend to choose my frames to fit wider tires.

To be fair he didn't mention anything about the tires, just the rims. 35mm at 90psi is too high but not dangerous, although it will definitely shorten the life of the rim, spokes, hub and tire itself.

700x23 Schwalbe One folders on the road bike's Araya CTL-370 622x14 rims. Usually 90 psi front/100 psi rear for rural chipseal, 100/110 for smooth pavement. That's a bit wider than the 700x18 tires originally on the bike. I'll probably try 700x25 tires next go 'round to ease the ride on chipseal. I doubt the bike would clear 700x28.

700x42 Conti Speed Rides (nominal, actually closer to 700x38) on the Univega Via Carisma's Araya PX-45 622x19 rims. The frame would clear larger tires but the front derailleur won't -- the cable clamp bolt protrudes too far. Usually around 50 psi front/60 rear, a bit lower on chipseal and gravel. Sweet tires for all around riding. I'll keep riding 'em as long as they're available.

If ur using a road bike, there’s a study saying that 25 width tires and 23 has exactly the same rolling resistance

https://www.planetx.co.uk/i/q/TYVIVO...r-folding-tyre

$25 per tire- 35mm. Folding 120tpi tire thats under 400g and extremely low resistance comparatively speaking. https://www.bicyclerollingresistance...ger-hyper-2016

I love em.

I'm sold on the "bigger is better" principle (with all the necessary caveats about tire casing construction). For a bicycle intended to be ridden on the road, up to 35 (or 1-1/2") seems good enough. I have 54's on one bike, and it's like riding on magic marshmallows, but I don't really want or need that on all my bikes. I just checked my two bikes with the tightest clearance, and it look like they'll both take 28s. For me, the challenge is dealing with the 4 or 5 that have tubular rims. I think they all have 23s or smaller. (suggestions welcomed)

This is my long-winded way of eventually coming around to saying that the 28 - 35 range is what I aim for.

I've been on 25c Gatorskins for about 5 or 6 years. For last year's Eroica I put 28c Gators on my '64 Legnano for the 12 miles on dirt and gravel. They did fine. I just put on a set of Pasela 28s on the Raleigh Super Course for next year's Eroica ( better hill gears than the Legnano), and they ride very well. I don't own a mountain bike, so 28s are the most bigIy I ride.

This is an interesting and timely (for me anyway) thread. After a summer recovering from a broken foot, I have been trying to cycle (get it?) every bike in the stable through my daily rider. This has meant two of my zippier road bikes which sport 23 mm 100 psi tires got some road time. The first thing I noticed was "wow, these road tires feel fast," but then thought about the BG article about speed perception vs actual speed (that we're hard wired to feel faster if there's a high speed vibration like one feels with road tires). Sure enough I got to work at the same exact time even though I would have sworn I was doing a higher avg speed.

I run 28mm Parigi Roubaix on my Colnago and use fairly low pressures of 60 - 70 psi, and over a set distance my times are the same as on a road bike with skinnies. I am, however, much less tired and sore (upper body mostly) on the Colnago.

I bought a C'Dale Slate this summer to celebrate my return to biking, and it rocks 650bX40mm tires, definitely not high pressure or narrow. I run them down around 35 psi and don't bother inflating them harder for road sections. My completely unscientific result is that my splits on hill intervals and times to work (a 42 min ride) don't vary between any of my bikes. I don't run a computer or use any phone app things, so my speed perception is all subjective, but my time splits are not. The one major difference I can quantify is that after 2-3 hours in the saddle I am much less fatigued on the wider tires, and the wider the tire the more I notice this effect.

Now, I fully admit all these factors can be attributed to many things other than tires. I am not interested enough to try multiple tires ont he same bike and record times or use a bike computer, I'm happy just accepting the differences but tend to relegate the race/road bikes with 23mm tires to shorter rides of 3 hours or less. Also I notice I get a lot more flats with skinnies, and I think I am pretty light on bumps and potholes. I flatted 3 times last weekend on one ride, my first 3 flats of the year. Three completely different mechanisms of flat too, one puncture, one center cut, and one pinch flat. Anecdotal again, to be sure, but I can't recall a flat on a tire 32 mm or bigger...ever.

So now this weekend on the Slate I'll flat FOUR times.

Having only a few bikes, I splurge on good tires (“Life’s too short to spend it on cheap tires”) and like the extra comfort with no weight penalty of the widest that fit. Much more comfortable on the rough concrete and chip seal found on PNW roads.

So three of the four have Compass EL. 700x32 Stampede Pass and 650x38 Loup Loup Pass on the Marinoni’s two sets of wheels, 700x32’s also on my wife’s Indy Fab, 700x28’s on the Miyata. I’m also using wider 23-25mm rims to gain extra tire volume. The 4th bike, which gets very few miles, has Panaracer 32mm GravelKings because that’s the best that I could find when I had to build this bike up very quickly.

BTW, I have been very pleased with the life of those Compass tires, and don’t notice any more flats (extremely few) then with previous tires. Hope I didn’t just jinx my tires!

How much do you weigh, Shawn? That's a good starting point for the discussion. Next would be road surfaces. Smooth? Rough? Hellish?

I average around 190, I mainly ride around 2 counties. One county has rough chip sealed surface, the other county has cracked concrete roads. My rides are out in farm country, I avoid cities and towns.

I've pretty much abandoned what many of us once considered to be the de facto 700 x 23 road bike tire. So several years ago I started going with the widest tires that I could comfortably fit on everything except for my very Italian Freschi. (That one has zero clearance for anything wider than a x23, and it would look pretty weird even if it would fit wider.) Hopefully I don't sound like I've been drinking the Kool-Aid, but the introduction of supple Compass tires - especially the EL versions - have simply been a revelation for me.

My data points include the following:

'66 Paramount - x28
'89 Paramount - x25 (no room to go wider)
'80's Freschi - x23 (same story - tightest seat tube clearance you'll ever see anywhere!)
'71 International - x38 - Compass tires sure made a difference over the bulletproof things I had on there for a while
'70's Carre - x32 - Compass tires
Boulder - x32 - also Compass tires
L'Avecaise - 650b x 42 (not sure this counts because it's purpose built for wide tires)
'46 Hobbs - x28

I really like x32 for the combination of sportiness and comfort.

My roadies have 23's, 25's or 28's (90 to 120psi). My commuter Trek has 32's (75psi). The 650b equipped bike has Gravelkings that measure out to a true 41 (45psi).
If I'm riding pavement, I'll take the 23/25's. Crushed limestone trails get the 28 or 32's. The 650b is almost entirely gravel bound. I weigh in at 220 these days.

Similar to many of the rural roads I ride. I use a 35mm Compass tire with EL casing. Works great. I was running 38mm but decided it was a bit too squishy. My bike will fit 42mm.

I'm running mostly tubular on roadies - 22mm Conti Sprinters (a few years old), 25 Veloflex, 26 Spesh Turbo, 28 Veloflex, 30mm Schwalbe. 23&25 for clinchers.

Schwalbe 35s on the tandem

2.0 X 26 on the old mtn bike (with a set of 1inch Richey slicks for back-up.)

All mine have 28s on back, and 25s on the front. Tim

On my Pro-Tour I am running Panaracers, a 700c x 42mm Tour Guard Plus up front at 55psi and a 35mm Tour in the back at 60 psi

I'm clearly in a minority here but ride around on 20c section tyres at 115psi. Only because I can't get any 19c tyres at a sensible price any more. Rolling resistance is minimal, but you need a decent saddle, proper shorts and time-limited running. If I spent all day in the saddle then I might have to venture to 23c balloons.

Z

I drank the wide/supple kool-aid, and find it works pretty well for me. I won't buy/keep frames that don't fit at least 28mm tires, and 32-35mm is probably my sweet spot----smoother and less fatiguing than 28mm, but still feels fast-ish. That's for pavement, which around here varies from smooth to pock-marked. If there's going to significant gravel, 32-33mm is the minimum, and 38mm/+ works best. But 35mm/+ overall feels a little sluggish on decent pavement.

And "feeling" does matter to me. Even if a 32mm-shod sport-tour bike isn't any slower over the same route than a racier frame crammed with 28s, and is even a little more comfy, sometimes I want to ride a hot rod. Don't care what the Garmin tells me, that extra little road buzz and the pedal snap lets me pretend I'm still in my '20s and feisty. But 23-25mm, at the pressures I'd need to prevent pinch flats, are a little too hot-rod for these old bones.