There shouldn't be a 22oz difference between the OS160 and the ZDZ if they are both optimized, that seems way too much to me. Do you have a breakdown of where the weight is?

Yes, the 22 oz is about correct. In the engine deparment alone we have:

ZDZ 40 OS 160

Engines 52.4 oz 33.2 The ZDZ 40 includes the igniton
Pipe 4.4 4
Mount 5.5 4.4
Prop 4.7 4.3
Ig. Batt 4.0 Includes the switch
Headers 4.7 2.3
Total 75.7 48.2

Therefore, the difference is actually around 27.5 oz. The glow version is really 9lbs 12oz so the numbers appear to be correct. Remember that this is NOT the ZDZ-F3A version. From the specs. the F3A version is around 7 oz lighter so the gas engine penalty is reduced to around 20.5 oz. You should be able to make the weight assuming that the plane is as light as the Abbra.

In regard the soft mount, that is your choice. I just reporting what happened. The Abbra is composite construction. If you do all wood structure it will dampen a little better. However, if I were you I won't take the risk.

Regards,

Vicente "Vince" Bortone