OK Guys,
I am no fluid dynamics guru and am generally impressed with the general
wisdom of this list.
However, with regard to this thread about lever shock oil...
Someone touched on motorcycle fork/ shock oil recently, which works
along the same principle. Thicker (higher #) equalling firmer damping
characteristics.
To a point.
That point being the one of CAVITATION.
Fork/ shock oil is generally 5 wt. To firm it up, you can use 7.5 wt. If
you want it really firm, go to 10 or even...15 wt. But 20,30...50???
Remember, the oil is being passed through orifices between chambers,
dispersing energy at a conrolled rate (damping). If the oil is too
thick, the pumping action causes the oil have a hole pushed through it
(because it cannot move fast enough). Thus, it becomes an air pump.
What's the viscosity of air?
How much damping can it provide? The answer to both questions is the
same: Nothing.
Which coincides with at least one lister's experience with 90wt gear
oil...
I will be attacking this section of my car very soon and am interested
in making the stock set-up as good as it can be. Any and all additional
info is always appreciated.
Kind Regards,
Mike
'73 TR6
CF703U
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