On Sun, 6 May 2012 12:32:16 -0400, "Jim Wilkins"
wrote:


wrote in message
.. .
...
Armstrong tire changer is fine - and a bubble balancer will do a
great job of "static" balancing a wheel. What it cannot do is a
"dynamic" ballance - which ballances the tire from inside to outside
as well. Great for rear tires, but sometimes you need dynamic on the
front to eliminate shimmy.

While I have no independent proof, I think my pinpoint balancer that
supports the wheel barely above its three-dimensional center of
gravity detects dynamic unbalance when the wheel is rotated. IIRC it
wobbled when spun by hand, after arranging the weights for static
balance.

Jim, do you already split the weight (using half inside and half
outside the rim) when you balance? That can fix quite a few of the
dynamic imbalances by itself. Another trick is to split large weights
(3+ ounces, more often found on older truck tires) into two different
lots set about 25 degrees apart, centered on either side of the
imbalance (or 4, 2in/2out.) Man, I haven't thought about doing that
for 30 years... Luckily, new tires seldom have very large imbalances.
But if someone stands on the brakes and doesn't have anti-skid, flat
spots really screw the balance...and roundness of the tire. =:0


While I was adjusting the balance I noticed the rusted-out shock
mount. I replaced the spring hanger and probably made the truck much
less sensitive to imbalance.

Yeah, most likely.

--
With every experience, you alone are painting your
own canvas, thought by thought, choice by choice.
-- Oprah Winfrey