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Old 04-21-12 | 09:25 PM
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dddd
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From: Northern California

Bikes: Cheltenham-Pedersen racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.

I just wrote down the exact dimensions of three popular standards.

Do you need any others?

I would "X" out that page in my Sutherlands book.
I've had to correct dozens of automotive repair manuals over the years.
Even the $120 factory manuals for Japanese cars have errors.

I should also mention that some of this same sort of bb spindle dimension data found in past Phil catalogs is unreliable, at least to the extent that it is applied to anything other that selecting from the choices that Phil offered. Sutherlands may have made un-verified conclusions based on that, or on other data intended for the application of perhaps other manufacturers limited product offerings.

EDIT:

I also will note that the JIS standard as applied by manufacturers has been the most consistent in accuracy by far.
You can find several hundredths of a millimeter variation in all other standards.

The 12.91mm shown would read 12.90 if I had used my normal two-handed method, but my other hand was taking the picture.

JIS is solid.

Dura-Ace 7400 is JIS.

Sutherlands published data was no good. Perhaps it has been corrected, but it's a little late in the game.
I would like for Sutherlands to at least specify an exact method of measurement for determining spindle taper dimension. They would then be able to re-write their chart if they just had a Harbor caliper handy on their desktop.
I couldn't more than guess as to where they got their data info, but they trusted an unreliable source or two, that much is plain to see.

The Harbor-sourced caliper replaced a good dial caliper here because of it's observed consistency.
It is an unbelieveably good instrument for the money.
I bought a spare 10 years ago and have never needed it.
You can use a JIS spindle to calibrate a lesser caliper!

Last edited by dddd; 04-22-12 at 11:19 AM.
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