Nice!
its really deceiving, cause its so smooth and quiet,
but once leaning near to get a tach read, i found myself frozen for a moment,,, suddenly realizing where my hands were,,, you could see no sign of a prop! guess it was spinning so fast lol

my no load (prop-disc) is basically a failure, it just sucks current.
and since my optical tach is only marginally reliable (indoors) anyway,
i'll be discontinuing it and relying solely on the Eagletree for rpm.
Note: ive still no Rm measuring device.
im annoyed, but... all this testing was largely for fun anyway so,
also, i didnt record any Io without the disc attached this round, so
all i really have is the 3s/gws8040 data from my gear.

aside from Rm, accurate Io, and my scale reads (which ive long suspected to be an oz. or so off) i'd say we're in the same ballpark.
Im gonna Have to build sumthin fer diz baby!

gws8040D 3s610 20C Rhino (wattmeter/globee/scale)
8.8A, 10.4v, 9960rpm ? 459g/17.901 oz.
8.3A, 10.1v, (rpm n/a) 407g/15.873 oz.

EagletreeV3 recorder file transcription
(3s610 w/gws8040)
02:25.00 10.28v, 8.90A, 10302rpm
02:28.00 10.18v, 8.71A, 10204rpm
02:32.00 10.08v, 8.53A, 10013rpm
02:35.00 10.00v, 8.40A, 10107rpm
02:39.00 9.95v, 8.40A, 10013rpm
02:43.00 9.90v, 8.34A, 9920rpm
02:48.00 9.88v, 8.28A, 9920rpm
02:48.00 9.88v, 8.28A, 9920rpm

Daves data
Tgy 2730 13T 24g dLRK Wye (V2)
Kv 1434 (17212r/12.08v) Io = 0.49 Rm = 0.168
Kv 1441 (11701r/8.12v) Io = 0.36 Rm = 0.168

GWS 8040 HD Hex 620 3S
10311 rpm @ 10.31v/8.42a 544 grams 19.2 oz/thrust 80.8% Efficient
GWS 8040 HD Hex 1050 3S
11290 rpm @ 11.76v/10.06a 656 grams 23.1 oz/thrust 78.6% Efficient

ive initiated this thread before having started in any way on the actual build,, in an attempt/the hopes of maybe gathering some interest and/or assistance in pre-determining the expected/potential increase/differential in performance.

the 'concept' is to take the stock 257 and basically add to it a bit....

stock : (upgrade)
22x4mm stator: (increase to 22x5mm = +1mm (25% stator increase)
4x4x1.5mm mags: (increase to 5x5x1.5mm mags, another 25%?? in area/volume?)

...which by my current thinking should drop Kv (by an equivalent 25% perhaps??)(also of course adding weight, the % which is as yet undetermined) and thus might allow for winding compensation:
IE: dropping a couple turns to retain original Kv, allowing for heavier gauge wire, reducing resistance.... etc etc

this of course will require alteration to the hardware, but i think it within my means.

build #2, still trying to get more comfortable with: dLRK, sharp teeny stators, mag placement, measurement accuracy,,,

i have to confess, much as i luv Don and the 'concept'
of the Magnet-Spacer,, in hindsight, ive had very little real success with em.

ive subsequently been using the 'bits-of-wire' method which Da V
had posted in the KH278 thread .
Its fairly tedious, but once you find the proper diameter wire,, very
effective oddly enough.
btw Roto-calc is a great tool for this as well, tho ive usually had to
over-gauge its recommendation for 'Gap between
magnets' somewhat.

my ponderance Now is:
should i just leave these bits-o-wire in there??

i had been prying them back out, and then filling the gaps with an
(15min) epoxy/micro-baloon mix, somewhat painstakingly applied
with earbud (q-tip) stems, and then the excess continually dabbed
off with another earbud dipped in acetone as it starts to set,,,
fairly 'frenzied' work w/15 min i tell ya!
..but in the end, fairly decent results so far.