<span style="font-size: small">Just a thought:
</span>The 69" QQ Yak 54; weighs 8.5lb =3.86kg;-was suggested for: 91-1.20 2/4 stroke glow http://www.fusionmodels.co.uk/69inch.html
-So appears to be rated at between 90-size and 120-size-perhaps can be called a 110-size plane ? -QQ planes were always built lightly ...

<span style="font-size: small">I wonder -does the 69" QQ Yak really need a motor as large and heavy as an E-Flite 110 ?
</span>However, I do note that Reza -who used to work at QQ Models -used an E-Flite 110 to convert his own QQ 69" plane ...
http://www.flyinggiants.com/forums/s...ad.php?t=30906 (missing bit in link is "FG" -RCUautomatically removes their name ...)</p>

Others have used a Scorpion 4025-12 motor for the 69" QQ Yak: see http://www.teamflyingcircus.com/foru...74/index2.html
-This Scorpion 4025-12 is a 347g motor with 440 Kv,is quoted to have max power of 2000W (has a 4025 stator)
http://www.scorpionsystem.com/catalo...s40/S-4025-12/
-At least as far as size, weight and Kv are concerned, it is similar to: Hacker A50-14 S V2, Kv 424 (345g) -which also has a 4025 stator.
However, the Hacker A50-14 S motor is typically used for 50-size planes like Sebart Angel 50, 3DHS Osiris 62" etc
-so (in my opinion) a Hacker A50-14 S -type motor would <u><span style="font-size: small">NOT</span></u> be large enough or powerful enough for the larger and heavier 69" QQ Yak -and anyway, the Hacker is rated for a max power of 1250W (not 2000W like the Scorpion) (-It is indeed quite surprising in the above team-flying-circus thread, they DID find the Scorpion 4025-12 motor large enough for the 69" QQ Yak ... )</p>

Many 110- and 120-size electric planes (-like the 69" QQ Yak) use a motor that is the size of Hacker A50-14 L V2, (430g), Kv 300
This is exactly the same motor as: HYPERION Z4035 14T 299 KV; LiPolice / Foxy 4035 /14T-310KVetc etc
See: http://www.rcuniverse.com/forum/fb.asp?m=11429728</p>

So it may be worth looking at some of these motors .... and other similar size motors.
<span style="font-size: small">It may well be unnecessary to use a motor as large and as heavy as the E-Flite 110, in the 69" QQ Yak ... -especially in these modern times with very high discharge 40C and 60C LiPo's available ...?</span></p>