Greetings Budd.

I'm driving on Yoko 370's and I use the spare regularly in my rotation.
I made a little chart to keep track of the mileage wear on the spare so
it is just as worn as the rest. Just in case I need to use it, I won't
worry about the VC.
To answer your question, I don't know how critical it is, but I have
read a fair bit in the archives that suggests to me that it is not a bad
idea to keep all the rubber as close to the same diameter as possible.

R.Feuerriegel
88 syncro

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