I asked if anybody knew what were the valve stem diameters used in Formula One...?

May be...

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Bunch of daffodil stems. 5.3mm on average.

$4 dollars a bunch...who'da thought that eh? $4 a bunch...I think they may have been forced though as traditionally they flower at Easter.

NB. Bad Bus Driving Wolf was probably drunk at the time mate, something that you may wanna take up as alcohol will lighten you up.
Aum...ding

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...and you would not believe the moron answers I got. This one fom Bad Bus Driving Wolf takes the cake: "I'm not familiar with F1 engines, but I do know two things: 1) the engines are "homoglated" which means the manufacturer is bearly able to change it; and 2) the engines are inspected by the stewards (especially if you are first). This means that a copy of the engine blueprints are held by the stewards so they can check the engine hasn't been changed. If the valve stem had a minimum diameter (and I cannot imagine why), then it would be plainly obvious to the stewards.
As I said, I cannot imagine why a valve stem of this diameter or that diameter is legal or illegal. That is like saying you have to have a particular diameter gauges in the car. While it is arguable this is a safety issue because the head of the exhaust valve could break and be ejected and hit someone (I did see a valve head come out at one race in 1983, but it didn't hit anyone and the engine failed), I think the probability of this happening is pretty small and there is more chance of person being killed refueling a car." Hey buddy, trim your mullet, you aint no Harry Weslake.
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