khutch

There are advantages to thinner, lighter tires, especially to racers. They may or may not outweigh the potential advantages (lower rolling resistance primarily) of wider tires, even for racers. Professional racers cannot get tires wider than 23 mm made to the specs needed for racing so they do not know if such tires would be better. I think they can get some second tier racing tires as wide as, oooh, 25 mm. The Michelin Pro3 Race and Continental GP4000s for example. But they won't run on second tier tires, can you blame them? The wide tires they use for rough courses are decent tires for those widths but not in the same league as their smooth road narrow tires. Like I said, I do not know if the super efficient tire materials are unable to run at the same pressures in wider widths or if they are unavailable in wide models simply because the manufacturers do not perceive a market for them. Tire engineers swear that when everything else is equal wide tires have less rolling resistance than narrow tires. In the real world, at present, it is impossible to find a wide tire equal in every respect to a narrow world class racing tire. And the converse is generally true too, you cannot find 23 mm tires made like 38 mm tires. So almost any real world comparisons folks like us would try to make between tire widths are hampered not only by our lack of instrumentation which forces us to rely on anecdotal results, but also by the fact that any comparison of a 38 to a 23 is of necessity an apples to oranges comparison.

The only thing we know for certain is that among the tires we can actually buy at the LBS and online the narrow ones are the most efficient. If you feel you need the most efficient tire for some reason, running a century perhaps, then you need to look at 25 mm and smaller. That is not a proof of the fundamental principles involved, just a fact dictated by what is on the market today.

The real advantage of currently available wide tires to a hybrid rider is that they are more suited to the terrain that hybrid riders tend to tackle and sometimes better suited on road bike terrain too. Penny Road in suburban Cook and Kane counties in Illinois is certainly a road. It is paved, listed on maps, and well traveled. If you want to bike it your road bike will be fine, your road bike tires will give you heartburn. Even on "roads" wider tires can be the weapon of choice. So I am looking at the most efficient 38 mm tires I can find. There is pretty much no independent data on them, the people motivated to take such data using lab equipment think that 25 mm is as wide a tire as exists. You have to rely on the manufacturer's catalog copy and while it is sufficient, most of the time, to let you determine which 38 mm Vittoria is likely to be the most efficient, it is completely useless at ranking Vittoria vs Continental vs Michelin vs Schwalbe vs .... They all make the world's absolute best tires, it says so right there in their catalogs!

Ken

common man

yes but do both tires of different sizes that you are comparing have the same tread?

big_al

to sum it up NO. The new tires have thread on the edges only the stock tires had regular thread.