ORIGINAL: beppeVRCS
12,600 with an 11x7 is not LOW THRUST. It's a very repectable figura for a non-piped .60, and an exceptional one for a 52.
I can understand a high revving 12x4 does not provide too much speed, but a lot of thrust for verticals...
I suggest to redo the readings...
Beppe
Good post! My thoughts entirely. That's a very good figure for a .52 on an 11 x 7 and should shoot a 2.5 Kilo model skywards very quickly.
If you can buy APC props locally, try the 12 x 4 or the 12.25 x 3.75. With these two props, your .52 should do over 14,000 rpm and about 13,200 rpm respectively and deliver lots of static thrust.
Asmund's right - the ASP .52 is very tolerant of a wide range of props and will put out class leading power at anything from 12K to 16K and beyond. For peace of mind, put high quality bearings in the engine if you use sustained rpm over about 14K.