> if you do the math you can quickly prove to yourself that reduced inertia isn’t doing anything for you.

This is exactly what I was talking about. People like to assume that a simple math equation tells the whole story, while ignoring the fact that bikers do more than just exist as rigid attachments to a bike that travels in straight lines.

I can do the math, but I can also swap wheels in a matter of minutes and feel the very obvious difference.

I'm talking about 29" mountain bike wheels, where the mass and moment of inertia is significantly more than what you see on 26" road bikes. It's palpable.

Maneuvering the bike in the air is another place where the mass difference is noticeable. Dropping 500g doesn't sound like much when you think about holding 500g in your hand, but it's a different story when that mass is on the ends of a 48" long wheelbase and you're trying to maneuver it in the 0.5s that you're in the air.

If you're just riding something like your tri bike in a straight line down a smooth asphalt road at a constant velocity then it obviously doesn't matter, though.

> I can do the math, but I can also swap wheels in a matter of minutes and feel the very obvious difference.

You’re not necessarily wrong, but I will point out that high end audiophiles will often say the same thing about their absurdly priced equipment, and then refuse to participate in a double blind test.

You meant 26 inch mtb bikes? 700c road wheels are also 29 inches

Done it. The place I most notice lightweight wheels are when climbing slowly on steep mountain bike stuff. Climbing like this is not a steady application of power like steady riding on the road; it's a series of small accelerations. When doing this lighter wheels are incredibly noticeable.

You also probably won't see this in your PM data unless you're getting data on partial pedal strokes.

More steady power stuff like on the road, climbing fast, etc? I agree that lower wheel weight just isn't something you'll notice. (Very good evidence for this is riding a fatbike on a fast rolling dirt road ride vs. climbing very steep fire roads.)

> if you do the math you can quickly prove to yourself that reduced inertia isn’t doing anything for you. you then either have to conclude that newtonian mechanics does not apply to bikes or perception can’t be trusted!

This is only true if you measure only along the forward/reverse axis.

Cyclists stand up, and rocking the bike sideways is easier with lighter wheels.

On mountain bikes there are even more cases.

If the pack accelerates out of a corner faster than me due to reduced inertia i will be off the back and can do the rest of the race on my own. That's something i have some experience with, unfortunately. If its a sprint i will lose the sprint. This is all normal mechanics. The only situation it doesn't do anything is in a flat time trial which starts with everyone already at the speed they will hold for the race, which doesn't have any change in road or wind conditions nor any corners. I doubt a race like that exists. maybe the triatlon comes closest because of the very long distances involved.