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On 4 Jan 2005 at 22:21, Hal Sullivan wrote: > Maybe SCAT is just pickier when it comes to measurement precision. I've seen some "76mm" cranks > that actually measure out to 76.4mm ..maybe the Scat 78.8mm crank is another instance of that. Not > that the "extra" 0.8mm makes much difference in the scheme of things.. While I totally agree that the difference is negligible, I can't believe this is just a matter of tolerances. Crank journals are ground to tolerances of about 0.0002". I'm sure the tolerance on the crank throw is larger, but It can't be much more than 10 times larger. 0.2 mm is 0.008" which is 16 times larger. Seems like way too much to me. [And if you're looking at this as a slip- up of 0.8 mm, then multiply this error by another factor of 4.] I work with someone who used to regrind cranks for a living, so I'll ask him how hard this is to do, and how difficult it is to adjust the grinder to the right throw. -- Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~