ORIGINAL: pauldo
The Zenoah 80 twin is not the ideal motor for this plane. It is very heavy, and down on power when compared to the 80cc singles. (It does make a great scale aircraft power plant, but not ideal for aerobatic aircraft where power to weight is a big consideration) Apart from the DA 85, the ZDZ 80 and MVVS / Evolution 80's are ideal choices for this plane. The early DA 85's had big vibration problems, but I understand that they have rectified this now. The ZDZ runs fairly smooth. The MVVS / Evolution, however, has 4 crank bearings. 1 rear, and 3 in the front. This is done to reduce crankshaft flex and deliver smooth operation (As smooth as possible for a big single)
The MVVS 80 has no rear bearing. It does have three front bearings though. The front bearing in a 3D plane is extremely heavily loaded by alternating gyroscopic forces on the propeller.