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PostPosted: Sun Nov 04, 2007 4:21 pm 
Old School Grand Master
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Hi,
Im no bike mechanic :oops: :roll:

I need a 68mm BB for one of my projects, will this fit?
(I did email the seller but they never replied)

Also how would I know for sure the Axle width is correct?

http://cgi.ebay.co.uk/Retro-Syncros-Titanium-bottom-bracket-BB-Fat-Chance-90s_W0QQitemZ300167503197QQcmdZViewItem?hash=item300167503197


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PostPosted: Sun Nov 04, 2007 5:00 pm 
Concours Judge
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Neil,

It looks pretty much like my Cook Bros bb, what means that you can slide the axle to allow both 68 and 73mm

118mm is a bit wide for a low profile crankset and a bit small for standard


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PostPosted: Sun Nov 04, 2007 5:19 pm 
Old School Grand Master
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http://www.bikepro.com/products/bottom_ ... able.shtml


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PostPosted: Sun Nov 04, 2007 5:38 pm 
Old School Grand Master
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Elev12k wrote:
118mm is a bit wide for a low profile crankset and a bit small for standard


Thanks, would you mind explaining that in laymans terms?

sorry to be a dumbass..

Im planning to use it with a 732 XT chainset and either 732 or Grafton cranks...will it fit with this setup???


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PostPosted: Sun Nov 04, 2007 7:01 pm 
Gold Trader
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neilll wrote:
Elev12k wrote:
118mm is a bit wide for a low profile crankset and a bit small for standard


Thanks, would you mind explaining that in laymans terms?

sorry to be a dumbass..

Im planning to use it with a 732 XT chainset and either 732 or Grafton cranks...will it fit with this setup???


hmmm...If I'm right what may happen is that if you use standard cranks you may take nice big chunks out of your drive side chainstay, and if they're low profile your gearing may spaz up a bit... all learnt from bitter experience :oops: Think the XT cranks are prob standard as may be the graftons but to be sure measure the diameter of the bolt holes from one side to the other (i.e the BCD). 110mm and you've standard, 94 and that's low profile. Tada! :)


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PostPosted: Sun Nov 04, 2007 9:04 pm 
Retro Guru
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I got one in 122mm if your interested?
J


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PostPosted: Sun Nov 04, 2007 10:12 pm 
retrobike rider / Gold Trader
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Quote:(110mm and you've standard, 94 and that's low profile.)

Low profile is the Q factor elimination.
Older cranks tended to run between 120mm and 130mm apart, which has a higher Q factor than the lower profile cranks that run a narrower bottom bracket. For example M900 cranks tend to run around 110mm and later offerings from various manufacturers can run even lower bottom bracket axles widths. Lower profile cranks run closer together in layman's talk.
It is a technical term for crank efficiency.

The terms 'compact' or 'micro' drive refer to the chainring pitch circle diameter (PCD), not the crank profile and can often be confused with one another. Indeed, 110 and 94 are the outer and middle ring diameters.

Hope this clears a few things up!


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