And yup again DuTch, 'tis very true!
There is quite a lot of stuff that's a real pain on some of the classic 'Metric Machines' too, especially a tendency to use 7mm and 9mm, often at 1mm pitch. Your average supplier won't have any of that, is for sure. Not always that easy to find threading tackle for some of the different pitches they used down in the 2.5 to 4.5mm area either.
But . . . at least metric spanners fit all metric bolts, even if the heads are often a size smaller than you'd expect for the shank.
It's not just 'continental' makes either - I cursed for hours when I broke the heads off a couple of undersized 12mm AF (but M8 shanked) seized exhaust header pipe retainer bolts on my XJR Yam a while back. Absolute nightmare to sort out with the engine in the frame, and I ended up making new studs and brass nuts at 13mm AF, which will be a lot easier to get off next time. (Bit like the ongoing sump plate discussion on here . . . Why the heck do people use bolts & setscrews in places where they are almost guaranteed to cause trouble down the line?!) Little Things that can Cause Big Grief, when the manufacturer's consideration only extends to the initial assembly of a new part in a clean factory environment.
