Campag4life

That is...riding on broken or rough road surfaces on 23's pumped up pretty high?. Yes we like to ride fast but most of us don't race all the time and the very skinny tires we ride do exact a cost.

Hope everybody is enjoying their summer riding season as much as I have.

Not riding as much as I would like but a fair amount of 30 milers at a decent pace on sometimes bone jarring surfaces which has caused me to experiment with my air pressure of late. I am just under 190 lbs and last night for my 30 miles I decreased my pressure to 105 in front and 110 rear...figured I was close to the margin of pinch flatting but luckily dodged that bullet or snake bite if you will.
A noticably better ride resulted and could keep up with my friends fine who are pretty strong riders as we set a fair pace in ideal weather conditions. I have just ordered 25's and believe that will be the ticket. I have ridden 23's for years but if can ride 25's with pressure about 95 front and 105 psi rear, I believe that will be all I need in terms of ride quality with only modest reduction in speed. I was getting to the point of looking into a cross frame so I could run 28mm slicks which would compromise speed further for even a plusher ride but I believe 25's with my carbon fiber Look 555 frame even on the crappy roads we ride, will be just fine.

Please relate any similar experiences if you would.
Cheers.

Creakyknees

I lol'd, seriously, when I read that you _lowered_ your pressure to 105/110. I weigh about 180/185 most days, I ride 23's, and I rarely pump either tire above 95. I don't pump 'em before every ride, usually just do a thumb squish test, hop on and go.

After a few days they'll get soft enough that the feel bugs me on the road, and I'll pump 'em next time. From looking at the pump gauge, that's usually about 80-85 psi before I get to that point.

Oh yeah, this includes racing, cat 4 and masters.

Rich_W

Riding high pressure on 23's or any road tire for that matter is clearly a noob thing. 100/105, 95/100, etc is far more comfortable, and greatly reduces the chances for cuts and punctures as the tire is more prone to conform to a piece of debris rather than burst/cut.

Take it one step further... get yourself a pair of Vittoria Corsa CX 320s in a 25... run 95/110 and you are a grip monster and total comfort.

heavyMetal

I weigh about the same as the OP; I used to pump my 23's up to the rated capacity - 145 psi, but after reading Psimet's tips I used his formula to get

Rear Pressure = 115
Front Pressure = 104

That felt a little on the low side so I went up to 130 rear, 120 front and still got a noticably less-jarring ride but just as fast as the 145 psi tires. Pressure is actually a little lowerr, since some air escapes when I remove the pump head. It's probably closer to 125/115.

calamarichris

I went to 28's @ 95-100 for a while, then accidentally learned that 23's do just fine at that PSI for my 185 pounds.
Less PSI = more comfort = longer rides = weight loss = less PSI =...

By the end of the season, I should be down to 65-70 PSI.

DaveSSS 

It's a common misconception to think that rock hard tires always have less rolling resistance than those with less pressure. That may be true on very smooth surfaces, like an indoor track, but on rougher pavement, the bouncing that feels fast actually has a slowing effect.

At 135 lbs, I use 100 psi in rear and 90 in the front. I need all the traction I can get on mountains descents.

Those who weigh 180+ should consider 25mm tires.

Brian Ratliff

175lbs: 105/110 front/rear for my 23c tires. For 25c tires I go 95/100.

noisebeam

At 185lbs I've used 25c 110/120 front/rear with fine comfort for several years. I just switched to 23c and at same pressure find equal comfort. In both cases I still feel a certain squishiness. I let them go down 10-15psi over a few days (weeks in winter) and can feel it and it does not feel better.

tadawdy

I ride 1 3/8" on my old roadie, not pumped rock hard. I agree that having a bit of compliance actually feels more comfortable and faster on bumpy roads.

banerjek

I find all the talk about comfort somewhat amusing -- that is not exactly what road bikes are built for. Also, if I'm out all day, very little of the discomfort I feel has any relationship to tire pressures.

I typically put my pressures in the 115-120 range which isn't exactly rock hard. Riding any lower makes the tires feel flat. Besides, having a little extra air can be nice since it buys you time to slow down properly when you puncture it.

I'll ride pressures below 110psi less the day I put one of those huge Brooks saddles on a racing bike.

couleeman

Recently switched to Vittoria diamante pro light 25's from rubino pro 23s: Although I have nothing negative to say about the rubinos, the difference is UNREAL. I am right about 200#, can run far less pressure and the 25s seemingly have less rolling resistance (cannot be absolutely certain of this however). Either way, I am not switching back to 23's anytime soon.

clausen

At first it does feel weird but you get used to it. Try lowering a few PSI every other ride. That air escaping is just from the head and not the tire.

Road Fan

I ride 28 mm clinchers at around 75/85 (front/rear), 21 mm tubulars around 100/110, 23 mm tubulars at around 95/100, 32 mm tubulars at 55/65 (Vittoria XN diamond tread), and I weigh around 180. I had 65/75 in the 28 Gatorskins, but got a small rim bash on a popular road, so I upped the pressure. These choioces are all loosely based on the Berto/Heine tire pressrue chart from Bicycling Quarterly.

thump55

A twinkie over two bills here riding 23's at 105/100. Never had a pinch flat....Vittoria something or others...

noisebeam

I've found that a 10-15psi drop in tire pressure results in about a .5% decrease in effective loaded tire circumference.

Doesn't seem like much and it isn't, but it does means that what previously was reported by a wheel sensor type speedometer as 20.0mph will now read as 20.1mph. Not a difference to worry about in practice, but you may end up thinking you are a (very tiny) bit faster if you don't also adjust cyclocomputer calibration.

caloso

When I go from my CF bike with 23mm tires to my steelie with 25's, it feels smooth and supple. Like an old man's bike.

Unfortunately, it's actually true.

thirdin77

You forgot to continue with a diatribe about how any road bike can be a comfort bike with wider tires, a riser stem, a triple and "a pizza cutter cassette".

ricohman

158lbs.
100 back 90 front. Seems to roll easier over the rough stuff at this pressure (for me).
It sure doesn't seem any slower.

LesterOfPuppets

25s are a nice ride and only a little more difficult to get past brake pads than 23s. I used to have a road bike that fit 28s, but deflating them to get wheels on and off the bike was a bummer.

urbanknight

The best thing I ever did for my riding was to lower my tire pressure to 95 front, 105 rear. I generally weigh around 150.

brian416

I really can't feel the difference between 23s and 25s, to me, tire pressure makes the biggest difference in ride quality

Campag4life

Truth be told, that is the purpose behind 25's....to lower pressure. General rule of thumb is almost a 10 psi reduction in pressure when running 25's versus 23's with the same probability of pinch flatting. This measurably increases comfort.
Thanks for all the comments. I know there are many that ride that pump their 23's up to 120 or so front and back.
By contrast, many that responded get it that to improve ride comfort, lower pressures are preferred. There is a Michelin calculator that gibes with Psimet's formula that puts me at 116 psi for my weight of 190. My tires feel pretty hard at this pressure. Further, the Michelin calculator doesn't account for the a reduction in loading of the front tire due to typical front rear weigh distribution of 45/55. For me running 105 front and 110 rear makes a substantial difference in ride comfort with no noticable loss in speed. If racing, I would likely pump up a bit more but for training, I prefer a bit more cushion. I believe for crummy road surfaces, 25's at 95/100 will be the sweet spot.

mazdaspeed

Why even use 23's on the street? Kinda like driving your car around with racing slicks IMO.

urbanknight

Not really. When I ride, speed is one of my goals. Not so much when I drive.

Drag

I'm about the same weight. 95 front / 100 rear on 23s.