Hello Jack,
I remember 50 years ago. Tires had not yet become radial. Many were not
perfectly round. The wealthier fanatics had their tires "shaved" to
round. I personally took the claims of reduced vibration & longer tire
life as snake oil. In good part because I couldn't afford the
considerable extra cost. I also reasoned that it was just cutting
perfectly good tread off & making worn tires out of new tires.
Belted tires came along & then radials. It was thought by many that this
new belted design eliminated the need for expensive tire truing & the
practice pretty much fell by the wayside. Fairly good results were
achieved as balancing equipment became more sophisticated. The so called
"road roller" balancing machines brought a whole new idea into the
picture in that they simulated actual tire to road contact. This method
may or may not compensate for out of round tires.
In the final picture, tires that are not perfectly round, some are
close, some are not, will benefit by shaving/truing that cannot be
accomplished in another way. The final touches for a perfect balance
job. If new tires are shaved, a really bad one can be detected &
substituted before it ever goes out the door. Few sellers are willing to
go to this trouble & even fewer buyers are willing to go to the
additional expense of truing tires.
For another reason, street tires used in competition are often shaved to
reduce tread depth & give more stability to the tread which results in
better traction/handling. I know from experience that there is no down
side to shaving/truing except the extra cost.
Dave Russell
BN2
P.J.Aeckerlin wrote:
> Well, in the 70's electronics were very expensive gimmicks. Remember the
> prices for the first desk top electronic calculators? Nowadays
> electronics are not only cheap, they give far more possibilities which
> is demonstrated by the latest balancing machines. Also the aligning
> machines (or what their name in the US may be) of the old days cannot be
> compared with the present ones. The 'tendency for a wheel to turn in or
> out' is now measured by one revolution of a wheel and is automatically
> compensated for in the measuring sequence that follows. And putting two
> weights on a wheel, opposite each other, to compensate is a method of
> the past as well.
> I would like to add, however, that 'shaving' a tire, like mentioned by
> one of the listers, is another possibility to do away with vibrations.
> It is sometimes surprising to see that brand new, modern tires slip
> through the factory inspection and are put on the market with over 100
> thou throw - I had it with a Michelin tire. And as you don't expect such
> a manufacturing error it takes a hell of a time before you find out!
> Jack Aeckerlin, The Netherlands
> 1964 BJ8 29432
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