The thread is not M6 1.0mm pitch - unless you force it

Wot is it, anyone know ? M6 with 1.25 pitch or some awful imperial stuff inflicted upon the radiator world - a throw back from copying the Germans , or worse still - Whitworth !! ??
Didn't even claim them to be thought of as M6 or even flippin' metric, but some odd thread that is so close that M6 will work if forced, and 20 years later make some believe it is M6. The factory bolts do not have that odd spiral thread that is a mechanical fastening method. The factory bolts fit nice, but other bolts from other points on the Subes do not fit nicely like finger tight, do not look like they have been forced t convert and is found on too many to be butchered in same way. To run a clean or even new M6 1.0mm pitch bolt through nuts cuts new thread on bolt !RSR 555 wrote:They are M6 coarse thread which is 1.0mm pitch. The only other M6 is fine which is 0.75mm pitch but this is too fine for these radiator bolts. I would say that someone has cross threaded these bolts.