What is the KV of your motor.  If it is the 610 KV it should be OK on 5S (18 V), with an RPM of 10980.  If it is 870 KV RPM would be high at 15660.  With the right prop the motor should be safe.

Hi Guil,
I'm afraid not. A Kv near 750 is most apprpriate for 5S.
Regards,
 Dean P.

I have had the power 25 and the G 25 side by side. It is NOT a copy of the power 25 as some are lead to believe. I have also heard, though not confirmed, that they are 10 pole motors which make them less than ideal for our use. If you are one of the few running obne with a 2.4 gig throttle system then it does not matter.

I have both an Eflite Power 25 and a Turnigy G 25 on my bench. I bought a G 25 on the rumor that they were the same motor as the Eflite. As Will has stated they are not the same. The physical shape and dimensions are slightly different. I visually counted the magnets in both. The Eflite has 14 magnets, the G 25 only 10. The difference is easily felt when rolling them over by hand. The cogging is much rougher on the G 25.

I’ve run them both for very short runs on a test stand. I used a KR timer set and tached at 9300 rpm on the Eflite on an APC 8-6 prop cut down from a 12-6. With the same prop and timer setting the G 25 ran at much higher rpm. I don’t remember the number right now but it was well over 12,000. I shut it down after 15 seconds, put it back in the box and set it aside.

I’m assuming that the KR timer is looking for a certain motor pulse count that equates with 9300 rpm on the 14 pole motor and to get that same pulse count from 10 poles the rpm has to be considerably higher. I suppose the rpm could be dialed back down but whether it’s safe to run that way, I don’t know.

Jack

To clarify, 14 pole motors work best for our use. Motors like the power 25, Scorpions, Cobra's, Axi, some Turnigy but not all , some Exceed but not all are 14 pole motors. Castle speed controllers seem to be the most compatible with 14 pole motors. This does not mean that Castles controllers cant be used with 10 pole motors as some people are doing. Like Jose says Howard is doing it very successfully. Since you already have the G25 I would try it but with a 4 cell pack and see how it works out. You can also get the G 25 in a 710kv version that you can use your 5 cell with. http://hobbyking.com/hobbyking/store/__19024__Turnigy_G25_Brushless_Outrunner_710kv.html
If you are looking for a budget motor an emax or aerowind might work well for you as long as you are willing to buy somewhere other than Hobby King The Emax/Aerowind 2826-06 is similar to a power 25 and will use a 4 cell battery. The Emax/Aerowind  Emax BL3526/05 is similar in size to a power 32 but will work with a 5 cell battery