Fork size
02-27-11 | 02:12 PM
#1
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From: California
Bikes: Trek 7.2 FX, Custom Vintage FG
Fork size
I measured my forks outer diameter to be 28.5 mm. Forks come in 1 inch (25.4 mm) and 1.125 inch (28.58 mm). Which size is appropriate as a replacement for my current fork?
02-27-11 | 03:33 PM
#4
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From: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
HUH???!!!
His fork measured 28.5mm which = 1.122", or 1-1/8"
To the OP, Forks are measured by the OD and as you noted, the standards are inch sizes. I don't get you, you measured your fork yourself and came up to 28.5mm or just under 1-1/8" and yet you so readily accept 1" (25.4) as the correct fork. You were better off before you asked.
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FB
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
Last edited by FBinNY; 02-27-11 at 03:43 PM.
02-27-11 | 06:22 PM
#7
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From: California
Bikes: Trek 7.2 FX, Custom Vintage FG
HUH???!!!
His fork measured 28.5mm which = 1.122", or 1-1/8"
To the OP, Forks are measured by the OD and as you noted, the standards are inch sizes. I don't get you, you measured your fork yourself and came up to 28.5mm or just under 1-1/8" and yet you so readily accept 1" (25.4) as the correct fork. You were better off before you asked.
His fork measured 28.5mm which = 1.122", or 1-1/8"
To the OP, Forks are measured by the OD and as you noted, the standards are inch sizes. I don't get you, you measured your fork yourself and came up to 28.5mm or just under 1-1/8" and yet you so readily accept 1" (25.4) as the correct fork. You were better off before you asked.
02-27-11 | 07:24 PM
#8
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From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Since my current fork is just under 1-1/8, wouldn't exactly 1-1/8 be a touch to large? That was my main concern. It wasn't exactly either of the sizes, but it would make more sense to go with the smaller one, as a larger one potentially wouldn't fit at all. Get me now? I'll measure the inside diameter of the headset and go with that me thinks. Thank you all for confusing me.
02-27-11 | 08:30 PM
#9
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Joined: Apr 2009
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From: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Don't be confused. For practical purposes 1.122 = 1.125, and you need a 1-1/8" fork. If you buy a 1" fork you'll be off by 122/1000ths of an inch which is in a totally ballpark.
Look at it this way. If you wear size 10m shoes, which would you buy, a slightly oversize size 10, or a size 9?
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
02-27-11 | 10:03 PM
#10
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From: California
Bikes: Trek 7.2 FX, Custom Vintage FG
There are nominal sizes, which is what we call things, and there the actual sizes which are close but not always spot on, since nothing is truly perfect. 3/1000ths of an inch is a tiny amount and within the manufacturing tolerance for this kind of stuff. Ot possibly you pressed a bit hard with the caliper and got a low reading.
Don't be confused. For practical purposes 1.122 = 1.125, and you need a 1-1/8" fork. If you buy a 1" fork you'll be off by 122/1000ths of an inch which is in a totally ballpark.
Look at it this way. If you wear size 10m shoes, which would you buy, a slightly oversize size 10, or a size 9?
Don't be confused. For practical purposes 1.122 = 1.125, and you need a 1-1/8" fork. If you buy a 1" fork you'll be off by 122/1000ths of an inch which is in a totally ballpark.
Look at it this way. If you wear size 10m shoes, which would you buy, a slightly oversize size 10, or a size 9?
