Not quite the same at all. Disc wheels distribute their mass evenly across the wheel rather than concentrate it at the rim. So while there would be an increase in mass near the rim it would not be the same as actually putting the total mass increase right on the rim or using especially heavy tires. Still, it would be nice to hear from someone that has ridden such wheels and then ridden the same bike with lightweight wheels and get their account on this. Or even from some racers that have sets of both and what they found in terms of accelleration for both the light box section rims and far heavier deep aero section rims.

In the meantime WHY, in real world terms, is my fishing sinker experiment so poor again? Yes there would be aerodynamic drag. But I'm not suggesting to ride a few kms with them, just to accellerate from a standing start a few times or from a slow roll up to speed and then back down. Aerodynamics would at most only play a minor part near the end of the accelleration. And if the SPLIT WEIGHTS (a standard fishing weight style) were crimped solidly to the spokes out at the nipples, or even over the nipples, why would they produce any friction? I wasn't suggesting that they be left loose on the spokes to slide up and down like kid's bike wheel beads

Oh, and see your bolded part? Thankyou for treating this discussion in SUCH an adult manner.

You've been quick to push our noses into the physics related to accelerating the bike and rider up to speed but then you flip off your hand at the question of how much energy is needed to bring the rims and tires up to speed during the same accelleration. And that is the crux of all this. When a wheeled vehicle accelerates the wheels accelerate twice. Once in the normal linear manner just to get the wheel up to velocity. The second manner is the angular acceleration needed to spin the two wheels up to a matching peripheral speed. In effect we're accellerating the wheel masses twice.

Those of us that have felt this effect don't need to look further, and frankly I'm not that great with the super fancy math that apparently involves "variable or selected constants" based on what ASI wrote. But obviously someone needs to run some numbers for what it takes to get some typical rim and tire masses rolling and then to match that up to what it takes to get the overall bike and rider up to speed. That would provide us with the complete picture since your often mentioned "wheels are at most only 2 to 3% of the total mass" only applies to the linear portion of the total accelleration issue.

Oh, Asi? While it's not possible to trackstand a motorcycle in the true manner as used by someone on a track bike it is very practical and common to come to a dead stop and "hover" in balance for as much as 3 to 5 seconds in extreme cases. When on my motorcycles I am often able to come to a full stop in a fine enough balance that I can remain feet up on the pegs for 2 to 3 seconds before I feel it start to go one way or the other. For a simple balancing act of this sort the weight actually AIDS the rider since it takes longer for any unbalanced but small force to actually accellerate the bike and rider towards the fall. What's missing is some way to kick the bike back and forth like a true trackstand to adjust the balance. On that front trials motorcycle riders have an easier time of it and by kicking the bike one way or the other can easily match a bicyclist doing a trackstand. The style of motorcycle seems to also make a difference. On the taller sport bikes and dual sports that I like it seems a lot easier to do this than on the lower and "feet forward" cruiser style. I'm thinking that it's the higher center of gravity but likely the rider's body position also aids in finding just the right balance point.