Hi Ice, thanks for the welcome, will do.
To take the thread a little further, the half worn tyre that came with the cb400/4 wheel (its the early 1970s model) is 4.00 x 18 the circumference of this is 230mm and that of the C5 is 210mm the width of both is much the same.
This in itself raises the gearing and will be tried before putting the smaller sprocket on. Also because the rim is narrower it would appear there will be a little more sidewall flexing. This may or may not affect the weaving characteristic of the C5.
I have reduced this somewhat by increasing the the front tyre pressure to 26psi, one of the pressures recommended on the iron barrel and the AVLs, with 28psi in the rear. I intend to experiment with these a little more. As I don't do much highway mileage I'm not too affected by it.
I bought the C5 to ride slowly with dignity, not to tear arse about. As it happens it does now keep up with my BSA mounted riding partners.
Thats it for now, Shappers