Why are M9 SS 1.25 pitch a 20/30 mm flanged bolts so hard to find

[McCabe-Thiele (Ted)]

If I have worked the size out correctly the captive headlamp earth nuts on the 400 & 500 are M9 presumably 1.25 pitch thread can anyone point me in the direction of a supplier for some SS bolts?

I had some SS hex headed flange bolts in my stock & could do with a couple more.

[K2-K6]

Sure it's M9 Ted ?

I dont know, but highly unusual to come across one....there's one in the cylinder head of XL 500 engine I recall.

[McCabe-Thiele (Ted)]

Not good with threads K2-K6  but my calipers show the diameter as 9.06mm on the unthreaded section with a 14mm flanged head.

[Matt_Harrington]

Ted, measure the thread section rather than the unthreaded part. The 'outer' dim of the threads is what you want.....

[McCabe-Thiele (Ted)]

Mystery is over they must be M10 bolts not M9  as I found a couple of NOS bolts in my stock of 400 bits that came with the bike p/n 93101-100320B - nice shiney chrome.

Looking at the part number using Kens information/logic  on part number construction they must be M10 x 32mm long B stands for chrome.

[Bryanj]

Probably "rolled" threads rather than die cut, supposed to be stronger