ornoth_cycling | Rolling Resistance

Back in June, on my third Bicycle House shop ride, I had a flat tire. Replacing my inner tube (plus a second tube and CO2 cartridge given to me by the ride leader) required a trip to the bike shop to replenish my parts inventory. In turn, that was an opportunity to finally try some changes to my wheel setup that I’d been considering for more than a year.

One change I made was simply making use of a new-ish tool that had been sitting in a drawer for months. I’ve struggled for years with how difficult it is to mount and dismount my tires, especially in a roadside repair. And recently moving to tighter-fitting “tubeless-ready” tires and wheels made that problem significantly worse.

The Tyre Glider is a little blue plastic device that makes both removing and installing tires considerably easier, replacing traditional tire levers and bulky tire jacks. After finally pulling mine out and putting it to the test, I can say it delivers on its promise. Not only can I get stubborn tires onto the rim, but I also don’t run the risk of puncturing brand-new inner tubes while mounting them. Two greasy thumbs-up!

Another item I’d been contemplating for years was a pocket-sized battery-powered inflator, which could replace both my frame pump and CO2 cartridges. These innovative little devices have become commoditized, and I used Amazon Prime Day to pick one up at 30% off. It’s the Fanttik X10 Ace Mini, from the same brand that makes the larger inflator I use for our car. While I haven’t used the Ace Mini a ton, my early results have been very positive.

Having struggled (as I said above) with mounting my tubeless-ready Continental GP5000 tires onto my rims, I’ve wanted to try a different brand, to see if they might go on easier. I’d heard positive things about Pirelli P-Zeros, and discovered that they still offered an expressly non-tubeless clincher version, which would be an easier fit. I picked up a pair of those and have been running them ever since. They feel great, and my only complaint is that they don’t seem quite as durable as other tires I’ve used.

At the same time, I also picked up some Pirelli TPU (plastic) inner tubes that I was eager to try. They are considerably lighter than traditional butyl rubber tubes, and are more manageable than the third alternative: latex tubes. A lot of riders keep TPU tubes as spares because they’re lighter and more compact, but I’d rather run TPUs all the time and have a reliable old butyl tube as my emergency backup.

Because I swapped tires and tubes at the same time, I can’t say whether the changes in my bike’s ride-feel were due to the P-Zeros or the TPU tubes… probably a combination. On top of that, the differences were pretty subtle, and I’m not the best at discerning minuscule differences in ride feel.

In comparison to my previous tires and tubes, it’s possible the new combination of P-Zeros and TPU tubes felt lighter, rode smoother, was a little quieter, held air a little better, and had a little less rolling resistance. But any difference was slight.

But there were two huge differences that were specific to the TPU tubes.

First was price. At around $30, each TPU tube cost three times as much as a butyl tube. We’re not talking huge dollars here, but for triple the price, I expected a vastly superior product.

And then there’s durability, which is where I’ve struggled to justify running TPU tubes at all, even though I really, really wanted to switch over to them. My first TPU tube lasted just 180 kilometers: 5 rides, or 8½ hours of ride time. The second went flat just 23 km into its first ride. The third didn’t survive 3 rides, or 86 km. That’s your three strikes; yer out.

So while running TPU tubes, I had 3 flats in 290 km; in contrast, my last butyl tube had served for more than 7,800 km! At that rate, I could run butyl tubes for $10 per year, or burn through $2,900 per year on TPU tubes!

The confounding thing is that those TPU flats were all on my rear tire, while the TPU tube I installed on the front has served flawlessly for more than 2,000 km! I guess the real test will be to move that tube to the rear wheel and see how much longer it lasts…

While I might prefer TPU tubes’ ride feel, they’re just not worth the cost, especially because TPU tubes just don’t work in real-life usage. End of experiment.

Before I close, I’ll share three other noteworthy purchases which don’t have anything to do with tires.

One was a set of plastic inserts from Risk that increase the size of the hidden buttons underneath Di2 shifter brake hoods. The stock buttons are really tiny, making them hard to activate. These simple inserts provide a larger active surface area, increasing the usability of those buttons. At $8 for four, they’re cheap, easy to install, and effective: just the kinda thing I like!

I also had to replace my big chainring, which was damaged during one of my many TPU flat repairs (long story). After I ordered the part, it took just 15 minutes for the Trek store to perform a while-you-wait installation. That’s a big improvement over the treatment I got at the Specialized shop earlier this year, which kept my bike for 15 days to do a simple tune-up!

And if you bike in Texas, you need to learn how to manage the copious amount of sweat you generate. So I’m currently testing the efficacy of double-width wrist sweatbands. So far, so good, but I’m afraid of getting even stupider (sic) tan lines, so we’ll see how that goes.

I might not have blogged much lately, but from an “equipment” perspective, it’s been an eventful summer!