Originally Posted by
Redbullet
25 mm tires are still used – see for example Canyon Ultimate CFR DI2, 10+ KEUR, with 6.3 kg weight. I think 28mm is overall better in aero setups (expensive aero wheels). But when producers force you to buy 28mm tires on common aluminum wheels, the losses from lower aerodynamics and higher weight might be bigger than gains in rolling resistance.
The same applies to weight increase: The very expensive bikes compensated for the extra weight of disk brakes and electronic group set by reducing weight elsewhere. But for lower tier bikes, this extra weight was only added to the bike.
The above might explain why a very expensive bike (say a “pro bike”) might perform today marginally better than its older equivalent, whilst a lower tier bike (say “casual rider bike”) performs today lower than its older (skinnier and lighter) equivalent.
That Canyon is an example of using 25 mm front and 28 mm rear tyres that I mentioned.
I would tend to agree that 28 mm tyres on narrow rims are not ideal (mushroom profile), but I think they are still better on rougher roads. IME they are definitely better on modern wider rims.
Whether or not a lower tier bike “performs” better or worse than an older equivalent depends entirely on your riding terrain and priorities. If it involves a lot of steep climbing then weight is inevitably a penalty for the newer bike. I think for everything else the newer bike is an improvement.
For me personally, the big difference is the higher volume tyres for long, hard century events on mixed roads. They reduce fatigue and are at least as fast rolling, probably faster on some surfaces. On a second tier bike I’m carrying 0.7 kg of extra weight, which I don’t notice (unlike the tyres, disc brakes and electronic shifting which I do notice).
Maybe for your riding conditions you are marginally losing out with a new, lower tier bike or maybe it’s just all in your head? Either way you may as well ride an older bike if you perceive it to be faster, better. You can fit narrower tyres on your new bike too if you really think they are faster.