geni wrote:wouldn't it be simpler and more precise by a drawing of assembly and tightening of the 4 wheels!
it will help a lot to better understand all these contradicting explanations
finally an opinion that we share
I use google translation" !
Geni,
As with most things, there is a lot of nonsense posted on the web on this subject. I am no expert, but I do have an engineering background, and I have done some research on this subject for my own edification.
From the best I can tell, the dominant effect that comes into play is 'mechanical precession' which I linked to earlier. All of the postings on the web about inertia of the the spinner, the wheel moving under braking and acceleration are written by people who don't really understand what is going on.
The direction of precession is driven by the relative diameters of the two fittings - in our case the male spinner has a smaller diameter than the wheel, in the case of the Rudge-Whitworth spinner, the female spinner is bigger than the wheel.
For the spinner to self tighten, fit the right hand threaded fittings on the right hand side of the car for the Elan and any other car with a male spinner. For cars with a female Rudge-Whitworth spinner (pretty much the rest of the world) the opposite is true, fit right hand threads to the left hand side of the car.
I think the 26R sheet linked to above was written by someone who didn't understand how the effect works. There are stories about Chapman having to educate his design team as they didn't understand it properly.
I am more than happy to be corrected - so please feel free to put me right.