Nope, you are correct. A larger blade(larger diameter disc) has a faster tip speed(edge) for the same RPM. I had both saws and the TS 55 does not have a better cut quality at all. Actually, I personally could not tell the difference in the cut, only the power when the wood got thicker.
I am not positive, but I think: RPM X Pi X Diameter / 60 equal tip speed. That's from memory we need to look it up.
Which means at max rpm the tip speeds are virtually identical(well very close). This can not be by accident.
Someone not so many years out of school can maybe verify or someone that still works in a science field.
TS 75 : 3550 *3.14*4.25 / 60 = 789.58 oops I used the radius you guys are supposed to be watching me!
TS 55 : 5000*3.14*3.125 / 60 = 817.70 oops I used the radius I guess the nub will just double then
I think this is better:
3550 *3.14*8.5 / 60 = 1579
5000*3.14*6.25 / 60 = 1635
If this is true I do not think this difference is nearly big enough make any noticeable difference at all in cut quality.
If I am way off base here just let me know and fix it, I'll change the calculations to make them correct.
As a side note that big 8 1/4 blade moving at 5500 RPM produces a tip speed that is most likely dangerous. 5500 * 3.14 * 8.5 / 60 = 2446!
Think about it, the larger the circular disks diameter the faster the outer edge speed will be because it is covering more distance during the same amount of time. So Rpm is only a good comparison for diameters of the same size.
Maybe Rick Christopherson can take a look at this and make corrections or correct the theory behind it if needed.