Has anybody used a Cobra 3515-18, 740 KV on 5 cells? I'm putting together a Brodak P-40 ARF profile converting to electric and have the 3518-740 in my box already. I usually run a 820 to 840 KV setup on 5 cells.
Hi Jim,
When my
Circulas 46 IIe (56.25” wingspan at 65.75 oz.) was first completed I used a Cobra 3515/18 740 Kv motor and Thunder Power 5S 2800 mAh battery with a 2-blade APC 11x5.5e prop. My battery capacity was between 20%-23%. This worked well.
The APC prop is a heavy prop at .84 oz. and suffered from the blades flexing is most maneuvers, especially square turns. I was told that this can be hard on the motor bearings. I found that the 2-blade Xoar 11x6e wood prop was lighter at .45 oz. and did not flex. My battery capacity rose to 22%-26% with this prop. With 80 flights using the Cobra motor and Xoar prop, this combination worked extremely well.
However when I started to experiment with 3-blade props, my battery capacity dropped down to 7%-10%, which was too low and so I ended up changing to Thunder Power 6S 2800 mAh batteries.
I have since changed to a Bad Ass 3515/18 710 Kv motor and a Igor 12x5N 3-blade carbon fiber prop with Thunder Power 6S 2800 mAh batteries and have almost 300 flights with this combination and haven’t look back.
Hope that helps.
Dennis