Hi
Wnet to take the bike out yesterday and the back wheel was flat so got the punture repair kit out and went looking for a punture couldn't see one on the tyre so I decided to pump it up and realised the valve stem had broken off the bike and was on the ground beside were it was parked pretty unusal so I just thought I'd ask has this happened to anyone else on a superduke or any other bikes you've owned in the past?

where is your bike stored? could vandals be responsible?

It doesn't look vandlised just looks like corrosion and then it got a knock was lucky it broke while the bike was parked up. It's the standard from factory valve stem so I don't really know it get it replaced in the next few days

I've seen it happen with rubber stems. Kinda scary knowing the metal could do the same.

will post up a pic of the stem tomorrow

Change the valve/Valve stem every time you fit a new tyre, I would not use right angle valves on a motorcycle again, You can also buy high pressure rated valves which are much stronger (what I use)
Check the valve / stem you fit meets the SAE 1205-1206 standard to and if you value your life not made in China

Its the factory original so hope its not a cheapy chinnesse one but who knows pictures as promised.

Looks like you had bit of luck the valve failed when the bike was parked

I wonder what the weather has been like in your area of late. If that lockdown nut was too tight is it possible that the heating and contraction of the wheel has caused a stress fracture (metal fatigue) ?