Anton M

I'm a bit late to the party, but you may compare different motors by entering your data into this online calculator. https://rcplanes.online/calc_motor.htm You may open separate windows for different motors and put them side by side to compare the results. Then click "Print Screen" on keyboard to copy the results into "Word" or "Paint" if you want to save and/or print them.

If you know or measure the plane's wingspan and then measure it on the drawing you've posted, you may find how much percent smaller the drawing is compared to the actual model and then calculate how much 140mm corresponds on the drawing. Hope it made sense.

This site might also be of help: https://rcplanes.online/setup_guidelines.htm

Transformed for the better or for the worse? Could you please provide more details, such as the plane's weight, props size, how many Lipos (voltage), motors' type, power, and KV? Thanks.

As already mentioned, the KV means how fast the motor will try to spin the prop at a given supply voltage. Lower KV means the motor turns slower for the same voltage. For the same motor size, prop and cell count (voltage), the motor with the lower KV would draw less current than a motor with higher KV. The power and current drawn are proportional to Kv³.

Here’s my two cents: The motor Kv is chosen depending on certain factors, such as the number of cells in series you’ve access to or are willing to use and the max prop diameter that fits your plane to produce the power needed to enable the plane flying the way you want. For a chosen power & prop, you may need higher Kv if only using 2S or 3S cell pack compared to using 4S or more. Or for a chosen power & cell count, you may need higher Kv if using a small diameter high pitch prop compared to a large diameter small pitch prop. You may find this link useful: https://rcplanes.online/setup_guidelines.htm

Here's another motor prop combo calculator (estimator) free to use online: https://rcplanes.online/calc_motor.htm

The Giggler: since your plane has a relatively long tail moment, the CG would be more aft than conventional. So, maybe the calculated CG is not far off.