Dave, I don't know for certain but I suspect that the clamp is used because it provides a degree of adjustment to take up the erm...dimensional inexactitudes of Commando frames. Depending on state of iso rubbers and final position of the motor, there is a danger of the assembly sitting under tension.
I'm also not sure that the original fixing points are in the ideal place as the plate on the head then needs to be larger and less rigid than otherwise.
In practice, the clamp does not seem to be a weak point. The clamp does not seem to have any tendency to loosen.
Coco, I suspect that if you have an imperial dimensioned frame tube then the wretched powder coat is the problem. Does the clamp measure 1" ID ? What is your frame tube OD ?
I'm also not sure that the original fixing points are in the ideal place as the plate on the head then needs to be larger and less rigid than otherwise.
In practice, the clamp does not seem to be a weak point. The clamp does not seem to have any tendency to loosen.
Coco, I suspect that if you have an imperial dimensioned frame tube then the wretched powder coat is the problem. Does the clamp measure 1" ID ? What is your frame tube OD ?