I don't know if the design was changed after I left the company - I didn't keep in touch.
In the original concept, side-to-side movement of the engine/transmission cradle was supposed to be limited by the polyurethane spacers between the isolastics and the attachment points to the frame. One design flaw that was fixed was the tendency of the spacer tube between isos on the same spindle from going bell-mouth shaped if the spindle nuts were cinched down too hard. There was a specified clearance between the frame and the spacers, so that movement in the plane of the engine was relatively free-moving but rocking in the cross-frame direction was inhibited.
I found that particular glitch when doing some fairly fast motoring on regular roads on the first prototype and discovered that our much acclaimed handling had gone to hell in a handbasket. On the high-speed banked oval track, we hadn't noticed it. A tear-down back at base uncovered the distortion in the spacer tubes. I believe the final fix was a washer, welded to each end of the spacer tube to give a bearing surface that would resist over-tightening.
The isolastic engine mounting system was the prime reason for developing the Commando. You can get equivalent handling for a rigidly mounted engine in the older Featherbed frame. My recommendation would be, if you want a rigid engine installation, sell your Commandos to someone who wants the isolastic system and go out and buy an Atlas or 650SS (but buy some good medical insurance for kidney-related complaints and lay in a good supply of headlamp bulbs).
