The Z2s ran wide in tread width (wider than the RS-RRs I have) @ 8.0" (vs. the 7.7" tread width of the RS-RRs).
The Z3s are right about the same tread width as the RS-RRs, and I wish that they were still wider, or even wider yet than the old Z2s, because I would get them next after the RS-RRs are toast, if they were.
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