I hate flats. My tires are 700×35, with 30 TPI, weighing around 500 Grams, and using Shrader valves, PSI range around 50 to 60 PSI. I first used Mr Tuffy tire liners, but had more frequent flats. I didn’t cut it to size, it was longer than necessary, so I thought it wouldn’t hurt, it turned out like some Amazon reviewers said that Mr Tuffy sticks to itself sometimes, or sticks to the tire, and when you go over a rock/broken pavement/uneven sidewalk, part of the tire wants to go one way, and the tire liner and tube want to go another way, so the tire liner makes an impression on the tube, and after a while this causes slow leaks. I guess that the same thing would happen with patches to a smaller extent, so I prefer to replace the tube if possible.
I then replaced the stock tube and Mr Tuffy with Forte puncture resistant tube on the back tire only, the new tube weighs 436 Grams, but I felt that someone replaced my wheel with a car wheel, or even an eighteen wheeler as a joke.
Finally, I realized that like others said, it’s better to have the puncture resistance on the tire rather than the tube, so I upgraded both tires to Continental Grand Prix 4000S II 700cx25 Road Tires, which have 330 TPI, divided into 3 layers, 110 TPI each. The difference in rolling resistance was substantial, I could accelerate faster, and even go uphill faster, but this could be due to me cleaning the hubs and re-grease the bearings. When going south on the W&OD from Hunter Mill RD to Vienna, which is slow steady uphill, I went from a steady speed of 8 MPH(original tires, wrong fit), to 10 MPH(original tires, proper fit, just lifting the seat one inch as all I did to gain 2 MPH), to 12 MPH(new lighter tires, 25mm wide instead of the stock 35mm, and cleaner hubs). All this speed increase was in the span of two months(March to May), so it’s unlikely because I have become more fit, in fact during these two months I didn’t push myself as hard as usual.
I have had two flats with the new tires, and they were my fault. I used two new regular Forte tubes. Flat#1 was slow, and was caused by me not paying attention when I was installing the tube. I dragged the tube around and it must have made contact with “invisible” sharp edges of my tools and the stuff I had laying around while replacing the tires. When I put the tube in water, I saw a string of shallow cuts along the side of the tube, like a series of pearls, but with no holes in them, except one which had a tiny hole.
Flat#2 has yet to be fixed, but I was getting very slow leaks and I think it’s a pinch flat when I went over an edge of a sidewalk harder than I should.
If you are using Presta valves, I highly recommend watching this video despite the poor quality and what seems that the video is ending in the middle. It covers common mistakes when working with road tires, particularly high pressure tires.
http://www.youtube.com/watch?v=Mpk6hRAV–Q
In summary, from the video and other sources:
- Throw away the nut that goes to the bottom of the valve, it causes flats at the stem.
- Inflate a new tube first outside the tire, then deflate it and put it in.
- Make sure that you keep the new tube at a clean place, without contact with any tools or components that may have sharp edges.
- Inspect both sides of the rim, and make sure that they don’t have sharp edges, otherwise they may cut the tube.
- Inspect the rim tape to make sure that it’s not damaged and that it covers all spokes.
- After putting the tire in, don’t inflate to the full PSI, only to a small number, like 30 PSI, and massage the tire so if part of the tube was not properly in place, it may cause flats later. See time index 6:15 in the video above for pictures that illustrate what happens. Wide tires, which usually use Shrader valves are more forgiving of these mistakes, because of the higher width and low PSI.
- Inflate to the recommended PSI.
- Checking the tire visually after inflation without spinning it is not enough, because it may not be obvious if the tube is properly seated. See time index 4:00 in the video above for details.
