I have a H-B C-Bow mount on my Stornello. Left side for reasons OP noted, i.e., high Arrow pipe on right.
For local day rides in staff & trailer reach -- code for "Kathi can come get me"
-- I often don't mount the (Orbit) bag. On overnighters or to places Kathi-&-trailer and AMA tow trucks won't go, I attach a H-B Orbit bag with tools, etc.
I have not noticed any handling effects with or without, but I am likely insensitive. Might be an issue if trying to Numero 46, but at my age, weight, and skillset, no issues.
I would think a single side bag is a better option than a top case high and on the rear. The latter are indubitably functional for storage and easy access, but one must be careful with cargo's weight. Panniers are mounted lower, thus lowering COG.
All of the above is for a Stornello, ridden like mine, which is never on the slab, rarely over 60 mph, and about 60/40 on/off pavement.
I miei due lire.
Bill
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