Thanks for that Swirly. Yes, the distance is fixed by the rails; what I meant is, on the bars, themselves, what is the minimum distance achieveable between the clamps; if this is greater than that of the rails then obviously will not work. If it is significantly less, then there's enough scope for adjustment. Your rail clamps seem to be very "deep" relative to the bars - from the front-on photo it looks like there's around 60-65% of the bar length between the ends of the 2 clamps, which would probably lead to the groove not being sufficiently deep on the 127s.
I measure the rails inner surfaces being 91cm apart at the narrowest (rear) and 97cm at the widest (front).
I've an old pair of 108s from previous car lying around and their 'clamp groove' is about 20cm each side. Assuming that all bars have 20cm groove each side, then the
- 118s have 78cm minimum spacing
- 127s have 87cm minumum spacing - which only leaves 2cm each side for the clamp to extend past the inside of the rails which is a bit tight.
Might just have to bite the bullet for 118s.Now to decide do I fork out for the blacks or settle for silver......