What is 47.5\50mm chainline FD?
05-23-23, 08:19 AM
#1
we be rollin'
Thread Starter
What is 47.5\50mm chainline FD?
I think my vernier caliper reads 48.8mm for the chainline on the bike. But are some front derailleur either 47.5mm or 50mm OR 47.5mm to 50mm?
oops, mod can you move to bike mechanics
oops, mod can you move to bike mechanics
05-23-23, 11:06 AM
#2
Junior Member
"Standard" road double chainline is 43.5 mm and basically as narrow as it gets. Things get wider as you move to triple front chainrings, mountain doubles, or touring/trekking cranksets.
How are you measuring your chainline and what type of cankset and bicycle do you have?
How are you measuring your chainline and what type of cankset and bicycle do you have?
05-23-23, 01:06 PM
#3
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The chain line your bike requires is set by the width of your rear dropout spacing and the number of cogs on the rear. So knowing how to measure it on the front doesn't really tell you what you should use.
Depending on whether you use the smaller rear cogs or the larger rear cogs the most, you can probably deal with a few millimeters one way or the other for your cranks chain line selection. It's not a will work or won't work, it's just a one will work better and the other not quite as well.
Depending on whether you use the smaller rear cogs or the larger rear cogs the most, you can probably deal with a few millimeters one way or the other for your cranks chain line selection. It's not a will work or won't work, it's just a one will work better and the other not quite as well.
Last edited by Iride01; 05-23-23 at 01:13 PM.
05-23-23, 01:11 PM
#4
we be rollin'
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I meant I think my chainline is 48.8mm. But I want to change the front derailleur to an Altus that says 47.5mm and 50mm. I don't know if this means FROM 47.5mm to 50mm or EITHER 47.5mm or 50mm.
05-23-23, 05:17 PM
#5
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I see this for an Altus 2X9 "One spec for 48.8 mm & 51.8 mm chainline." So works for either. Maybe link your specific model to be sure.
05-23-23, 06:09 PM
#6
we be rollin'
Thread Starter
OK, either. Well it's an Altus FD-M310. Not the typical type but how do you say again, the one that looks higher.
EDIT: I meant a top swing rather than a downswing.
EDIT: I meant a top swing rather than a downswing.
Last edited by hybridbkrdr; 05-24-23 at 04:54 AM.
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