The 661 was a friend who uses it nearly every day and has multiple bars..I think it was on a lighter than standard bar .He did tell me that these populars were so hugeI have a 3120xp with a 42" bar I use for milling, would be a horrible thing to use for felling and even cross cutting would be a fairly unpleasant experience with it. Much better with a 661 or 395xp. A 36" bar must be on the upper limit or even over the limit of being balanced on a 661?
I have a 30" bar on my 395xp and a 25" bar on my 288XP and the 288XP feels about right balance wise.
that he felt safer using that size bar.He took the tension out of the middle of the trees first before placing them but said it was still interesting.
I run a husq390 on 24" and a stihl 460 on 20" for general farm use and find them
both well balanced.