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Old 07-20-10, 08:07 PM   #1
chico1st
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How do i measure...?

Hi there how do you measure stem length? Like the forward extension.
From the centre of the allen bolt to the centre of the handle bars?
How do you account for stem angle? If a stem isnt parrallel to the ground is the given length parrallel to the ground or along the actual stem?

I have a number of bike fit numbers which use the nose of the seat as a point of reference. Ie. nose to handlebar length but dont saddle nose lengths vary between different saddle makes? How can it say my nose should be X inches from the bottom bracket (horizontally) isnt that completley dependant on nose length?

Last edited by chico1st; 07-20-10 at 08:47 PM.
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Old 07-20-10, 08:12 PM   #2
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center line of the handle bar (1/2 D) and the center line of the fork ,
typically the center of the Bolt hex socket.
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Old 07-20-10, 09:04 PM   #3
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I had thought the measurement was simply taken along the length of the stem, from center-to-center.

Then a forum member informed me that the stem length is the distance from the center of the handlebar mount to the center of the steerer tube (or quill in the case of threaded stem) at a right angle to the steerer tube.
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Old 07-20-10, 09:11 PM   #4
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Nope. only if it's a 90 degree stem .. its thru the extension shaft from the line thru fork axis to bar center line ..


even if its a 40 degree up angle. thats what the manufacturers stock them as.

there is an effective length calculation to compensate..
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Old 07-21-10, 10:53 AM   #5
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Any idea about the use of the saddle nose position? Is there a typical seat length? Or just this just sound crazy to you?
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