[F500] Balancing

[Dan Morency]

I don't know what the intent was with allowing lighter pistons... As you
know these are pressed, roller bearing cranks. They were originally aligned
and balanced when manufactured, that is why it should be allowed. Typically
the SCCA does NOT allow lighter than stock parts in "stock" classes...
Allowing lighter parts does muck things up a bit. I would assume that the
only balancing allowed would entail drilled holes to balance the assembly as
done in stock ANY machining outside of that would be "bending" the rules and
should cause DSQ! Therefore it is NOT a legitimate excuse to machine the
crank. :-) Since these are 8-9000 rpm rotating masses balancing should
always be done to maximize life. Any out of balance condition can yield
dramatic increases in stress, shortening component life with sometimes
catastrophic failures. (My mechanical engineering background again...) Stock
parts would vary very little in mass, not much "adjustment" up or down for
balance should be expected.

Dan
----- Original Message -----
From: <dphaneu at attglobal.net>
To: <f500 at www.f500.org>
Sent: Thursday, January 16, 2003 12:47 PM
Subject: [F500] Balancing


> Dan
> So I can take my rotating assm. to a machine
> shop and have it dynamically balanced adding
> or removing weight as needed??
> The sorta newly approved wiesco pistons
> are somewhat lighter than stock Kaw pistons,
> is this a legitimate "excuse" to machine the
> crank??
> Two strokes need to have the crank pressed
> back together in correct alignment  ( an occasional
> hammer tap!) but not always necessary to do a
> balance job.
> Dave
>
>