[Shotimes] (3) Detailed On -The- Car Spin Balancing (Extremely Long)

[George Fourchy]

Part 3

If your tire passes the static test, which means it does not shake up to about 45 or
50 actual road mph, half that on the speedo, but shakes when you get up to 70 or 80
actual, you probably have a dynamic problem.  This is easier tackled with two
people, because one will need to mark the tire with the crayon as it spins.  Study
the sidewall first to find a totally smooth area, one with no writing or serrations
or other marks that will 1. quickly wear out the crayon, and 2. cause false
markings.  Then spin the tire....have the other person do the spinning while you sit
and mark it,because you will know what to look for after reading this....looking for
a sudden side to side vibration of the sidewall and tread.  When this happens, hold
the crayon extremely steady, with both hands, next to the clear portion of the
sidewall, and carefully move the tip of the crayon in towards the tire, finally
letting it just barely touch it, marking only the high part of the sidewall.  Then
stop the tire, and study the markings.  Depending on the severity of the imbalance,
you will have a lot of marks on just one small slice of the sidewall, or perhaps
almost 
half way around it.  Weight amounts to correct this are just a guess to start.  Try 
using 1/2 ounce for the small mark, and 3/4 ounce for the large one.  Cut off two
equal sized pieces from the stickon strip of the proper size, and go ahead and apply
them permanently to 1. the rim, as close to the front side as you can, but behind
the
spokes, aligned with the center of the marks you made on the sidewall, and 2.
EXACTLY opposite this point on the backside of the rim, but on the flat part above
the bead.  If you don't get it exactly opposite, you will induce static imbalance,
and have to do the first part over again.  Now try spinning up the wheel again, and
see if the dynamic shake is better than it was before.  If it is still there, but
less, apply 1/2 the amount of weight to both places again, making sure they are
exactly opposite each other, irrespective of  the first pair of weights.  You can
apply stickons on top of each other if necessary.   See why they are better than
clip ons??  If the dynamic problem moves, as per another crayon test, try removing
part of the weight you put on the first time, moving the removed portions closer to
where the second dynamic imbalance showed itself to be, by reading the marks on the
sidewall.  Clean the sidewalls off with cleaner every time you stop the wheel,
otherwise you will confuse yourself with lots and lots of marks.  

You may or may not be able to get all the dynamic balance problems out of your
tires, but you will make them much better and not so noticable above the rest of the
road noise your tires pick up.  By far, most of the problems with balance are
static, not dynamic.  What happens when tires are balanced improperly, by putting
too much weight in one place to get rid of a static problem, is that a dynamic
problem is created.  When you spin balance tires on a car, you USUALLY can solve
both problems by the strategic placement of only one or two weights.

The Rear Tires

If you don't have, like most non fanatics, (me not included!!), a wheel balancer in
your garage, you will need to either borrow one, or do the rear tires on the front
of the car, as described above.  You will induce two problems into your
balancing....the inherent imbalance of the rotor in the front hub, and the inherent
imbalance of the rotor in the rear hub.  If you could convince yourself not to apply
the brakes while you are doing this....almost impossible.....you could remove the
rotor from the front hub while doing the rear wheel on the front.  But then you
wouldn't be able to stop the wheel from rotating when you wanted to.  I have found
that the error from front to rear is not usually...not on the Lowrider
anyway....noticable enough to be felt on the road.  There might be a quarter ounce
or less difference between perfect and what you get, but that wouldn't be noticed,
even with Tokikos or Konis, because you are not actually connected to the rear
wheels like you are the fronts with the steering wheel.  Really badly balanced or
totally unbalanced rears are felt through the car seat and seat of your pants, while
the fronts are felt and seen through the wheel and dash.  You do need to make an
effort to do the rears, because that throbbing through the but really gets tiring,
and it will also wear them out quickly...we all know that.

If you do have access to a spin balancer, do them the same way as you did the
fronts.  Start at the valve stem and narrow the choices for the light spot down to
your best choice, and apply the weight.  My Hunter balancer will take them up to
about 80 mph, if I manually (with a screwdriver) open the caliper a little bit.  

Over time, and also, naturally, when you rotate tires, the balance will shift and
change.  If you rebalance the tires periodically, you will want to remove the old
weights and start over.  A big screwdriver or putty knife will take them off, and
then you can clean up the adhesive with brake or carb cleaner, and you start from
scratch all over again.  But you did it yourself, and you did it for nothing, other
than the weights themselves, and you got a better balance than you can buy anywhere.

Be careful.....Enjoy!!