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Re: Dashpot Oil

To: Larry.E.Quirk@gov.ab.ca
Subject: Re: Dashpot Oil
From: James <james.carpenter@ukaea.org.uk>
Date: Tue, 7 Apr 1998 08:00:21 +0000
According to the Workshop Manual you should use the same oil as you have
in the engin.  Provided you have the correct oil in your engin, the
dashpots should behave them selves.  I have a feeling multigrate oild
may not be the right thing to put in the dash pots, so if you have a
multigrate 5W40 for example in you engin, then you should put the oil
Triumph recomends for your temperature range in the dash pots.

The damper acts in almost exactly the same way as the shock adsorber in
your car, and you should never use any abrasives on it.  Like any
working part of your carbs.  It presents a strong force to a light push
up, slowing the rise of the damper, but if you push it up quick i.e.
when you accelerate, the piston goes up fast the force presented will be
less than when the piston goes up slowly.  All thanks to the chap who
invented fluid dynamics.  When the piston goes down the damper moves
about increesing the hole through which the oil travels.  This meens it
presents a lot less resistance going down, because there is no way to
force the damper down, and if is acted a shock it would never go down.  

BTW the piston goes up and down, moving the tapered needel up and down,
the needel is graded for about 8 thicknesses along it's length, the
diference of the area of this thickness - the area of the jet hole give
you the effective jet diamiter for a given road condition.  So
effectivly you have a carb that responds to road conditions by varying
the thickness of the jet.  
 
The Haynes Carburetter or SU manual is grate for this info. 
The SU is cheaper, but it don't cover all the carburetters. 

-- 
James Carpenter
Yellow '79 spit wired by a trained marmot

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