How can you tell how narrow your BB should be on fixed gears?
10-09-07, 08:42 PM
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How can you tell how narrow your BB should be on fixed gears?
I have a converted Panasonic and I think the mechanic put in something like a 68x119 - it just seems like the Q factor is kind of wide (my heels are about 1 1/4 from hitting the rear chain stays).
The chainline is OK, but it good be better. How narrow can I go? I see 69x103 is the narrowest. Would something like 68x107 68x109 be a safe bet? I use 175mm cranks and hav size 12 feet. I want a better chainline, but don't want to start slamming the chainstays.
The chainline is OK, but it good be better. How narrow can I go? I see 69x103 is the narrowest. Would something like 68x107 68x109 be a safe bet? I use 175mm cranks and hav size 12 feet. I want a better chainline, but don't want to start slamming the chainstays.
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10-09-07, 09:34 PM
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I have a converted Panasonic and I think the mechanic put in something like a 68x119 - it just seems like the Q factor is kind of wide (my heels are about 1 1/4 from hitting the rear chain stays).
The chainline is OK, but it good be better. How narrow can I go? I see 69x103 is the narrowest. Would something like 68x107 68x109 be a safe bet? I use 175mm cranks and hav size 12 feet. I want a better chainline, but don't want to start slamming the chainstays.
The chainline is OK, but it good be better. How narrow can I go? I see 69x103 is the narrowest. Would something like 68x107 68x109 be a safe bet? I use 175mm cranks and hav size 12 feet. I want a better chainline, but don't want to start slamming the chainstays.
See: https://sheldonbrown.com/chainline and https://sheldonbrown.com/bbsize
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10-10-07, 05:52 AM
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Is your ring in the inner or outer position? If it's on the inner then you could move it to the outer with a shorter spindle. But the most important issue is the chainline. If you're using a standard flip/flop or track hub you need 42mm.
10-10-07, 06:26 AM
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a) have not provided any information whatsoever
b) really have to measure stuff out for yourself
10-10-07, 02:27 PM
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Inner. 120mm hub spacing. I am using a Mavic CXP Track wheel.
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10-10-07, 03:46 PM
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You can't generalize about BB spindle length, because it varies with the configuration of the specific make/model of crank you are using.
See: https://sheldonbrown.com/chainline and https://sheldonbrown.com/bbsize
Sheldon "It Depends" Brown
See: https://sheldonbrown.com/chainline and https://sheldonbrown.com/bbsize
Sheldon "It Depends" Brown
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+---------------------------------+ | Is ambivalence a bad thing? | | Well, yes and no. | | -- Garrison Keillor | +---------------------------------+
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10-11-07, 02:07 PM
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10-11-07, 02:50 PM
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10-11-07, 03:18 PM
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Wasn't aware of this. Why wouldn't the spindles be equidistant?
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10-12-07, 02:04 PM
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