Pinch Flats
 

Are there any tire/tube/rim combinations that are particularly resistant to pinch flats? Any that are prone to same?

I'm currently running Vittoria Open Corsa Evo CX's with light weight butyl tubes on Panceti SL23 V1 rims, and each of my last 2 rides was interrupted by pinch flats despite making sure the tires were properly inflated. Both of these happened when riding over small (< 1") bumps at moderate speeds (< 17 mph).

Thanks

Tubulars.

What's your bike+rider weight?

What pressure were you running?

How wide are your tires?

How wide is that rim?

In my experience, a narrow tire on a wide rim is more likely to pinch flat since it's shorter in cross section than the same tire on a narrower rim. I've spent a lot of time on 24mm wide rims with 25/26mm wide tires and have had quite a few pinch flats due to gravel and "golden-bb" type rocks. I've even had two pinch flats on the same tube at the same time. I try to keep my tire pressure to the point that I get 15% sag under load but sometimes it's a little over or under.

It's generally a combination of tire pressure, rider+bike weight and terrain. Your best bet it to up the pressure or increase the tire size.

Or you could always go 650bx42.

Even better, tubeless.

This is the best option, though it doesn't help you out any.

I find it odd that your pinch flatting with the description your providing. As asked previously, what's your weight and tire pressure?

This /\ or you could try some Tufo tubular clinchers. Or simply pump up your tires to 100 or more psi. What is your body weight?

+1. I flat in over 2 years of riding tubeless and that was on a tire that was way beyond its useful life.

Plenty cyclists, including myself, have never pinch flatted running regular clinchers and tubes. I might run higher pressure than some charts spec, but I don't like flatting and my pressure seems to be working. I also get very few puncture flats but I probably ride further from the edge of the road than most cyclists do.

Does this mean that solid rubber tires would be better than better? I hear the ride quality is stupendous!
Bicycle Tires

Once I started inflating my tires properly and getting out of the saddle when I came to big (more than 4 inch bumps) I've not gotten a pinched flat.

The SL23's are 24mm from outside edge to outside edge. My tires are rated as 23mm, but are actually a shade over 25mm when fully inflated. I'm running 105 psi in front and 110 - 115 on the rear. The bike weights ~17.5 lbs, and I tip the scales at 200 (and dropping :)).

I do have a set of tubulars, and I'm well acquainted with their relative immunity to pinch flats, but I prefer to save those for special events, especially rides that will include a bunch of climbing.

I've considered going tubeless, but don't know that much about them. How do they ride compared to more conventional set ups? Do they add much weight? Is there a decent selection of tires that can be used in a tubeless configuration?

Thanks!

But we are addressing the OP, not plenty of cyclists. Plus, the tubeless ride is great.

If you're considering going tubeless, I would wait for the new Vittorias to come out. Seems like they will be the real deal, although I fear they might turn out to be extremely expensive.

OP, it sounds to me like you need to learn to un-weight the bike when coming to things that might cause a pinch flat. Get yer butt outta the saddle man!;)

I'm your weight, and I put ~8k miles on a set of Pacenti SL23 V1 rims with tires inflated to 90psi rear and 80psi front without any snake bite problems. To answer your original question, I rode 23mm Michelin P4 Endurance tires.

You might also want to loose those lightweight tubes and save them for race day...

I just did a bit of googling about tubeless, and what I was able to find was less than compelling. Most of the comparisons I found of tubeless vs tube found rolling resistance to be a wash between the 2. They all agreed that the tubeless set up rode smoothly but were felt rather dead. Since I don't race, that's probably no cause for concern. There was also a consensus that puncture resistance was far better and that pinch flats were essentially eliminated. However, these benefits seem to come at the cost of more difficult repair if you do get a significant puncture and a set up that is a bit fussier to maintain. To me at least, pros don't overwhelm the cons enough to justify the added expense.

That said, I think my best bet is to 1) continue to shed the body ballast, 2) be more careful to get out of the saddle at the first sign of any incontinuity in the pavement, and 3) go to more robust tubes. As a last resort, I might try a 25mm tire.

Sound reasonable?

Yes, reasonable.

But if you want to virtually eliminate pinch flats, tubeless is certainly the best choice.

Use "advanced search" to look at the ten thousand threads on this topic. Most people who have gone tubeless are pleased with the results. I think it's too much hassle, but then again I get like 1 pinch flat a year so not motivated to change my setup.

The OP's high rate of pinch flats is unusual. If "plenty of cyclists" manage to avoid them, then. just maybe, it's something unusual (and correctable) specific to the OP.

A bit higher pressure or 25mm instead of 23 (at around the same pressure) if they fit.

Your rate of pinch flats is oddly high (or, maybe, you are unlucky). There isn't, IMO, much point to extra light tubes. 25 mm tires should help significantly and they aren't really slower.

njkayaker,

Let me try to put my situation in better perspective. I've been running tubulars (mostly Vittora Corsa Elites) for years with very few flats up until returning to riding after a lengthy hiatus back in May of this year. I'm not sure what changed, but there's been a noticeable increase in the amount of roadside debris around here, and I started getting an unacceptable number of punctures. Hence the change to clinchers about 2 months ago.

Things were going just fine with the described set up until this last weekend. I got one pinch flat while on a club ride. I believe it was a ~1" step up in the pavement at a bridge crossing that got me. The next day, a similar discontinuity at another bridge crossing, this one hit a higher speed while planted in the saddle, got me the second time.

I don't know that this constitutes a trend, but I can think of several factors that might contribute. First, I had been riding very little for two years prior to getting back to cycling seriously at the beginning of this summer. During that time, I put on a bunch of weight (one of the motivating factors in my return to the sport). Secondly, as a long time tubular user, I'd gotten pretty lazy about un-weighting the bike when confronted with these sorts of relatively small bumps. And finally, in an attempt to preserve the tubular "feel" as much as possible, I've been using light weight inner tubes.

As you said, all of these are things are fixable. It's just taken discussing the issue out in the open to help me think clearly about it. Thanks for everyone's help.

I don't think there is anything inherently wrong with your setup, though I would try 25s next time. With shoes, helmet, water bottles and so forth, I'm probably not far below your weight. I run 25mm GP4000sII on SL23s, 75 and 90 psi, and I've yet to have a pinch flat. Jinxed myself?

There's your problem. Those bridge crossings.

I don't think your pinch flats have anything to do with tubes/tyres/weights/pressures (although the latex tubes probably aren't helping).

I always try to bunnyhop bridge crossings/changes in pavement because you never know exactly what sort of surprise is in store for you at those suckers. And if I'm not going fast enough to bunnyhop I get out of the saddle, pop the front wheel over first and then bunnyhop the tail wheel over.

If your bike+rider weight is 217 pounds you should definitely use 25mm tires and most likely would be better served by 28mm or 30mm tires. Are you racing or riding in fast group rides? There's no speed loss from moving 23->25 and very little when going from 25->28.

But as mentioned above, the specific cause of your pinch flats is due to rider error while encountering road furniture. I've double flatted both tubes on a square-edged railroad cross plate that I'd ridden over dozens of times at a slower speed.

In fact, there's some evidence that there is a decrease in rolling resistance going from 23 to 25. So add me to the cacophony of monkeys suggesting that you try 25s.

I think my bike (the one listed in "My Bikes") will accept a 25mm tire, but rather than spend the money on tires, I'll try the measures I've outlined above first. But I certainly will keep the 25mm option in mind.