My piggy was boiling today coolant reserve tank blewn up

Have been on test today with my bike.
The auditor let in run for about 20 minutes on idle for measuring the "co" (exhaust).
Then the water started boiling and the coolant reserve tank blew up  
I was warning him but he did't follow my afford to stop the engine when not moving the bike. It has no fan as u know, men I'm "eaten up" as we use to say in Austria  

Use big fan , they do boil fast when stationary .  

send the auditor (inspector?) the bill!!!

Remove the thermostat and operate the bike with out one. I bet your thermostat is bent.

Look here how the overflow connection looks like  



And here a pic from the blewn tank:




Does Your overflow connection (it is inside on top of the tank) look like mine ??? Or is it open?

Never mind the blown tank, your engine is fooked!
If it boils for that long that the tank melts.... then the engine is toast!
Next time when you need (read: MUST) idle it for long run a hosepipe over a radiator, this works well when doing work on it with a running engine.

Besides, an expansion tank (and this one for sure!) is not supposed to blow up - like yours did by the looks of it!
The cap on it must have sealed, and it is not supposed to, so check that when you get a new one. The cap must ventilate to the atmosphere, better know it. This then also will tell you that the engine is way too hot, it will leak coolant which you will notice.

Oh, and lastly, the testing the idiot did is invalid as the engine was WAAYYYY too warm - but I suppose you could not care less?

I hope, the engine has no damage in case of boiling water! I suddenly pressed the kill switch when the tank blew up. Maybe at lot of the 65oigers had boiling water, but when the reserve tank is open maybe many did not recognice - I guess? Why some give a 1.6 or even a 1.8 radiator cap instead of the 1.1 which also is built on mine?
As I wrote in a posting before, I told the inspector after a 10 minutes about that there is no fan - he did not hear to my words. If the engine is harmed I'll send him the bill!

The pressure in the cooling system stops at the rad-cap, the tank is at normal atmospheric pressure - or supposed to be. Yours clearly blew up hence my remark regarding the cap, it did seal instead of vent like it is supposed to do.

That inspector must be an idiot , if i was you i would take the top end apart to give it a good check , you might be lucky and all is fine but its best to be sure .