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Fork steerer lengths Do mfrs measure above or below crown?

Trail-blazerTrail-blazer Posts: 129
edited March 2010 in MTB general
Right had a bit of mare? Bought some forks on eBay listed as having a 255mm steerer. I've got a retro GT that has a 160mm head tube so I need a usable steerer length that is 250 long.

Only one problem. The guy measured from below the crown so I've only got 225mm of steerer which is 20mm too short. I assumed everyone selling forks measured from above the crown - how else would you know if they'd fit your bike?

The manufacturers state this fork has a 255mm steerer. :?

So what's the craic - do fork manufactures measure steerer length from above the crown or below?
I had my sig deleted and all I got was this snide replacement. Not happy. :(

Posts

  • nicklousenicklouse Posts: 50,675 Lives Here
    looked in the FAQs the answer is there.

    it is from where the crown sits. any other measurement is useless.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • nicklouse wrote:
    looked in the FAQs the answer is there.

    it is from where the crown sits. any other measurement is useless.

    My thoughts exactly but the eBayer seller is saying that the forks are 255mm long and uncut and the factory website says the forks have a 255mm steerer so either they've had 30mm lopped off them or that's how the factory measures them. :?
    I had my sig deleted and all I got was this snide replacement. Not happy. :(
  • nicklousenicklouse Posts: 50,675 Lives Here
    he is bullshitiing you.

    what is the fork?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • NorthwindNorthwind Posts: 14,675
    You are being fibbed to. But...

    "I've got a retro GT that has a 160mm head tube so I need a usable steerer length that is 250 long. "

    How does that work? 40-45mm stack height for a typical stem, 30mm for a headset...
    Uncompromising extremist
  • If it helps, Crank Brothers do a range of headsets that have an 11mm stack height and you can get good stems that have a 35mm stack height, which I think would solve your problems.

    I'm running the Crank Brothers Cobalt headset with a Pro FRS stem as I was in a similar, but self-inflicted, situation to you.
  • Northwind wrote:
    You are being fibbed to. But...

    "I've got a retro GT that has a 160mm head tube so I need a usable steerer length that is 250 long. "

    How does that work? 40-45mm stack height for a typical stem, 30mm for a headset...

    That figure was me being uber-cautious and allowing for 20mm worth of spacers. If the spacers weren't needed, I could always have trimmed the extra 20mm from the fork as it's easy enough to shorten a steerer but not so easy to lengthen one. :lol:
    I had my sig deleted and all I got was this snide replacement. Not happy. :(
  • If it helps, Crank Brothers do a range of headsets that have an 11mm stack height and you can get good stems that have a 35mm stack height, which I think would solve your problems.

    I'm running the Crank Brothers Cobalt headset with a Pro FRS stem as I was in a similar, but self-inflicted, situation to you.

    I think I can get away with using a 35 - 40mm stem with my current headset with no spacers (or one 5mm spacer if I find a 35mm stem) and a stem with a bit of rise and a riser bar if the front end seemed a bit low . I know FSA do 35mm stack height stems but they all seem to be from the OS range.

    Anyone know of a 35mm stack height stem for standard bars?
    I had my sig deleted and all I got was this snide replacement. Not happy. :(
  • nicklousenicklouse Posts: 50,675 Lives Here
    lots out there or use shims.

    might be worth giving a clue as to the length you may have been looking at.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
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