My LBS suggested I try thorn resistant tubes after my latest flat. I picked up a nail in my back tire. I am not so sure it was a good idea. I was really enjoying being able to go a bit faster on my new Giant Escape vs. my Giant Cypress, but the new tubes in my bike tire may the bike feel so much slower. My ride this morning verified that as I rode almost a full mile per hour less than I had been doing. I will give it a week, and if I can't get used to it I will change back to the regular tubes. Anyone else use thorn resistant tubes?

I question the wisdom of the LBS suggestion. A thorn and an nail are pretty different unless it was a really small nail. Are these tubes self-sealing like with Slime? That might help for a while - maybe enough to get you home.

I'm more of a fan of puncture resistant tires. If the nail or thorn can't get to the tube, the tube doesn't have anything to do except its normal job of holding in air.

As far as the 1 mph difference, maybe you were just having a bad day.

I'm not surprised. The thick thorn-resistant tubes add a considerable amount of rolling resistance in addition to the increased weight. As the tire rolls you flex both the tire sidewall and the tube inside. The thicker tube takes significantly more energy to flex than a regular tube and slows you down.

Heavy But Effective .. the rolling resistance is not too bad when up to pressure But it lets you know when your Psi Drops

Made a 10 Month Tour of western Ireland and Scotland without a Flat tire in '97... It was Fine, I was Not in a Hurry.

They're in Both My Bike trailer wheels and My Bike Friday too ...

Though for air retention Im favorably Impressed with the Schwalbe A/V 4 tubes I Got for my Brompton.

How much time are you losing on commutes, or out of your pleasure riding time?

After four flats last month - three in one weekend - I was ready to sacrifice a little speed. Not that I was fast anyway. In particular I didn't want to be caught out again facing a long walk home with the bike on my shoulder - because the original tires rolled right off the rim when flat, so I couldn't simply walk the bike home.

First I tried some Nashbar self sealing tubes in my original tires (Specialized Hemispheres - regular, not Sport, Armadillo, etc.). The self sealing tubes felt heavier in my hands, but I can't say I felt any difference when riding. The Hemispheres felt great overall, on pavement and unpaved trails, grass, lumpy ground, etc. The Hemispheres can handle 75-100 psi and felt about right to me at 85-90 psi (I'm 5'11", 170 lbs).

But after picking out another half dozen grass burrs deeply embedded in the Hemispheres, I decided on new tires too - Michelin Protek Cross Max. They feel much heavier in the hands, at least 50% heavier than the Hemispheres. I'm doubtful about the manufacturer's specs. Specialized claims around 800 gr for the Hemispheres - I'd guess they're much lighter. Michelin claims around 1,000 gr for the Protek Cross Max - and they feel all of that.

But the Michelins feel only a little slower when riding. I can feel the weight on uphills. I can feel some difference off the pavement too, especially on wet grass over lumpy ground, but that may be resolved by tweaking the pressure. Around 80 psi feels right for pavement. Probably 50-60 psi for unpaved stuff.

Despite the weight, it feels a lot faster than being stuck on the side of the road fixing a flat. And the tires stay on the rim when flat, so I can roll the bike if necessary.

Wish we'd had these choices 30 years ago when I commuted almost daily. Back then one particular route I took in SoCal, the shortest to work, practically guaranteed one flat a week. I remember being thrilled to try the first folding tires. They were much easier to change than those thumb-buster Continental clinchers that I preferred for the speedier ride.

My thoughts exactly.

Look into some continental gator skins. They're more than worth the investment. I've pulled glass, staples, and all sorts of road debris out of tires and it didn't puncture the tube, nothing made it through the actual tire. There's a guy at my shop who is pushing 3000 miles on his current set and hasn't had a single flat.