tate65

I have been running 700X28s all year at 85 psi. But I have had 3 pinch flats over the past month. Every since pothole season has come around. One road I ride has so many you can't avoid them all, and I had another one today. I was thinking of going to a 32 or 34 both of which my bike will handle. What's the down side? I used to commute on a MTB and never had one pinch flat.

JeffS

How much do you weigh?

I'm around 200 lbs and always keep my 28s well over 100. The only downside to the wider tires that I can think of is rotating mass.

dynaryder

What tires? 85 psi may be too soft,check your sidewalls to see what the inflation range is listed as.

Also,have you checked to make sure it's not your rim tape? 3 pinch flats in a month sounds excessive.

tate65

85 is the max on the side wall. I run my raod tires at 120, I am just over 200#.

savethekudzu

I run 700x35s at 80psi; this doesn't sound right.

JeffS

Does anyone else ignore these numbers, or is it just me? 85psi is too low for your weight and these tires. If you're not comfortable overinflating them you should probably look into changing tires.

greenstork

I run 28mm Conti Grand Prix 4-seasons on my bike, always at or over 100 psi. I agree that 85 psi seems to be on the low end of what a 28mm tire is capable of, pressure wise. Before abandoning the tire, check the inside of the rim for inconsistencies, and the rim tape as well. The last time that I was having repeated flats, old rim tape was to blame.

Banzai

All the 28s I've seen have consistently been in the 100 PSI range for max. My 32s run at 95 PSI. What kind of tire is it?

Oh, and ditto on checking the rim tape and sidewalls.

ilikebikes

guilty I ride what feels right to me....which is usually the recomended amount

mynameisphunk

My 700x28 Kendas on the Redline 925 I just picked up say 90 max on the sidewall, and the ride feels pillow-soft compared to what I'm used to. A lot of that may be the steel frame, but even compared to my rigid steel MTB it just beats me up WAY less, despite the tires being so much smaller than the MTB.

I'm also right around 200lbs, and hope I don't encounter the flats you are with tires right around that pressure.

idcruiserman

I weigh 205 and ride my 25mm Ultra Gatorskins at 95 to 100psi. I think 90psi in a 28mm would be reasonable.

option.iv

I believe you should move to thinner tires, like 25 or 23. The heavier you are, the more pressure you need to support yourself. I weigh roughly around 200, maybe more since I haven't weighed myself in a while and I run 25s currently (I have a set of 23s to put on whenever my tires need replacing). I check to make sure they are always at least between 90-100 psi. Any lower and I'm asking for pinch flats. Also being "light" or posting on your bike can help reduce pinch flats. Before I would hit uneven juts in the ground and for sure I would get flats as a result of taking the bumps with my butt and most of my weight. But ever since I learned how to post and be lighter on my bike, it helped reduce the pinch flats to zero.

I generally don't ignore the numbers because I went over the psi on an older tire and could see it slowly destroying the sidewalls and tread. I usually go for max psi since I really don't care about the "ride" and would much rather prevent flats instead.

edit: Since you're riding a road bike, you don't have the luxury of shock absorbers as you did with the MTB, so posting (using legs as the shock absorbers and slightly unweighting the saddle) would probably critical if you want to reduce flats.

JeffS

I'm not following the logic of going thinner.

Don't get me wrong, I have 23's on my fixed-gear, but it's more I tend to think that you need a certain volume of air to support your weight. A wider tire with lower pressure will support you just as well, if not better than a thin tire with really high pressure.

I forgot to mention tire quality in my original post. I bought a used bike once with 23's that kept pinch flatting even at higher pressures. I switched to a higher quality tire and at the same pressure never had another pinch flat.

greenstork

I was about to say much the same thing. Width has no bearing here, other than that width is usually inversely correlated with max tire pressure. Any two tires at the same pressure will basically have the exact same contact patch on the road. That said, for the OP's problem, a little higher tire pressure (max psi) could be the culprit here and as others have pointed out, this can be solved with other/different 28mm tires, and even wider tires in some cases can be inflated to more than 100 psi.

In Absentia

When it's not winter, I run 700x28 Gatorskins at 120 psi, though the recommended max is 116. I weigh almost 300 lbs and have had almost no flats in more than a year with these tires. You should probably look into different tires, either wider tires to maintain the lower pressure or 28 mm tires with a higher maximum pressure.

SDRider

How much do you weigh? If you're getting pinch flats I'd suggest you increase the pressure in your tires.

I've never had pinch flats on my road bike running 700x23 tires but I run a bit more pressure in them than you do.

RadioFlyer

airfreetires.com

dynaryder

The Vittoria Randonneurs that came on my Big Buzz were 85psi max,as were the older model Specialized All Conditions that came on both my old Sirrus Sport Discs.

I'm 180 and have never pinch flatted a tire. If the OP is running his tires at the max on the sidewall,then I'd say he either needs better tires,or something else is amiss. Could be the rim tape,the bead of the rim,or maybe the bead on the tire is screwed up.

al-wagner

I weight 200 lbs. and on my 23 I run 90 lbs on my 32 I run 70. And I NEVER had a flat.

tarwheel 

If you're having pinch flats, most likely it's because your tire pressure is too low. With colder weather, the pressure in your tires goes down, and it's probably less than the 85 you may have pumped them to. Also, potholes are more common in winter, and they are notorious for causing pinch flats. I've got Panaracer Pasela TGs in size 700x28 on my commuter bike, and the recommended max pressure is 105. I usually pump the rear tire to 100-105 and the front tire to 95. I usually repump the tires every 3 days or so, so the pressure probably drops during that time to 95 rear, 90 front. My recommendation is to increase your tire pressure, refill more frequently, and try harder to avoid potholes.

BTW, I don't I don't get flats very often, and I think a lot of that is due to refilling my tires often. I commute on my bike with the Paselas about 4 days a week, and I haven't had a single flat since putting them on in July, riding about 1,300 miles during that period.

tate65

I checked the pressure that morning right before I pulled out of the garage 85psi, and that may be part of the problem. It was 64 deg in he garage and 26 deg on the rode. Yea potholes are bad this week after a week of cold rain, that section of road is one big pothole after another. I hit that hole total not ready so all of my weight was on the seat so the rear took a hard hit. I also travel a lot of bad road to avoid cars, I cut through 2 strip club parking lots many days and the glass is horrid, but it saves me getting on I35 access road for 1/2 mile or so and that may contribute to the high amount of flats. I also have about 1/3 of a mile on a dirt path, and that's the second reason for the fatter tires.