View Full Version : ? about motor/battery choice

08-12-2005, 05:32 PM
Hi, New to EP flying. Was given an Aspire EP sailplane which after first flight was really underpowered with the stock 550 motor/7.2( 6 cell) Nicd battery and 8x4 folding prop. Really weak set-up!!!! I located the following to upgrade. An E-flite 600 motor with a 2.8:1 built in gearbox/ 11x8 Folding prop included and also a 30 amp ESC from E-flite. It came stock with a Maxx 25 esc which states that it is good up to a 550 speed motor. My question is with batteries. I located some 7 cell 8.4 1100mah NiMH batteries. Would these be a good choice. The motor is rated as per the website at 8.4 volts. I am looking at increasing the climb rate to reach altitude and shut off motor ....and glide with maybe 1 or2 more climbs per flight if needed. Any input would be gratly appreciated....thanks. Peter

08-12-2005, 05:40 PM
That setup will likely draw 20+ amps and unless those are GP1100 NiMh they will not be up to the task.

I would highly recommend that you go with some GP2200's or 1950 faup sanyo cells.

Try here for them:


08-12-2005, 06:06 PM
Thanks Mike...you have to bear with me as this battery thing has me confused. The batteries you recommended seem to be 9.6 volt batteries...dont I have to use an 8.4 set-up if thats what the motor is rated for????? Is the Eflite Maxx 25 esc ok to keep with the upgrade or should I still go with the upgraded 30 amp mini model......sorry but I have flown off a high start with my sailplanes for years and this electric stuff is all new...thanks for you help and patience

08-12-2005, 08:34 PM
You can do as many cells as you would like with them. 7 cells would work fine to keep you under 25 amps.....


08-12-2005, 10:49 PM
I agree a seven cell would have been a quick and low cost upgrade. Since all you are doing is getting up there it would be a short run. If I remember right that is the only weak point with the Aspire.
Gainesville fl

My hobby shops are 50 miles in all four directions. Fortunately they are close to the quilt and fabric shops.

08-13-2005, 12:29 AM
I was amazed at the difference in responses I got from all the places I called.....It ranged from " just use the 6 cell 7.2 Nicad battery it came with......" to "you need at least 10 cells to get performance" I talked to N.E. Sailplanes in Vermont who ran all the numbers for 600 speed 2.8:1 motor with an 11/8 prop and 30 amp esc and they came up with an 8 cell NiMH 1900mah battery pack that is roughly about the same size as the stock nicad and they said this would give me the desired performance to climb to soaring altitude. Does this sound like a good setup. They said that the battery was rated at 9.6 volts....I told them the specs on the motor said that it was an 8.4 volt ....they said that didnt matter....is this the case??? I hope to pick up more of the tech stuff as time goes on....then again I bet I could launch all this electric equipment pretty far into the lake with my high-start.Thanks for all the input....what do you think of this battery for the motor set-up I will be using...thanks, Peter