Since the YS 4 strokes are rear induction, the motors tend to be really long front to back and I don't think they would fit in a Fury without a serious modification of the bottom plate. On the SE and Pro with the stacked frames that wasn't a problem but the Fury needs the plate for rigidity. It could be redesigned to fit around the motor but it would be unique for each brand of motor and since YS is not making the 91 heli anymore, it make take several tries to find a motor that would work.
I just happen to have a new YS 91 ACH in the box that probably would work with a little effort . (Just kidding, it's for sale with an SE 4 stroke conversion)
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