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Old 10-28-2015, 12:58 PM
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ZAGNUT
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general rule is to go over size by 1/1000 of your bore diameter...1 micron per mm or 0.001" per inch.

so about 0.02mm should be good. heating your hub to 150C over ambient will make it around 0.05mm too large which should be a nice slide on fit. removal will be the hard part as you are now heating the steel as well which has half the thermal expansion as alum....so better to err on the loose side. if your hub has gotten a good heat soak at the above temp and it's not a drop on fit you might want to polish the mandrel a hair and then try again.

also, make sure the bore size you go with will accommodate the socket needed to tighten the crank nut. i chose 19mm out of convenience and then had to shave a socket down to fit....