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Old 07-28-05, 02:37 PM   #1
bkennedype
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Cannondale fork replacement...advice needed.

I am replacing the fork on my Cannondale road bike - headshok suspension and busted fork. Found a cane creek reducer for headtube that is a reducer and a headset - thank you freeranger for the advice on this - very nice actually - so now I can use 1 1/8 carbon fork and everything seems like it will fit nicely together. The measurements on the bike are as follows...7 inch head tube, 2 inches where suspension extends below the headtube, total 9 inches from top of headtube to top of fork. After I remove the headshok suspension it looks like I will be losing the 2 inches where the suspension will no longer exist...should I increase the steerer tube length above the headtube to compensate for this, and if so by how much. Or is another solution like an adjustable stem a better choice to get proper handlebar height. Thanks.
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Old 07-28-05, 02:51 PM   #2
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Quote:
Originally Posted by bkennedype
After I remove the headshok suspension it looks like I will be losing the 2 inches where the suspension will no longer exist...should I increase the steerer tube length above the headtube to compensate for this, ..............
That won't gain you anything where you need it. If you have a CF steerer it wouldn't be advisable either.
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Old 07-28-05, 03:08 PM   #3
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I'm no expert, but it seems like if you want to retain proper geometry you need to make up for the missing headshock with fork length between the axle and the head tube.
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Old 07-29-05, 03:15 PM   #4
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I only saw one Cannondale road bike with a headshok on their site, and it didn't seem to have any extra length above the headtube? Seems that below the headtube is where you would have to make up extra space. I'd watch that whatever fork I had, had the same distance from the bottom of the headtube to the axle as it did when the headshok was on. Otherwise, you'll be lowering the front end. I'm not familiar with the Cannondale line, but I'd bet that one of the online shops specializing in road bikes could offer some pretty good advice-like harriscyclery.com (Sheldon Brown).
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Old 07-30-05, 08:49 AM   #5
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I'm curious about this too, I've got a T800 Silk Tour, has the headshok suspension. I'm contempating switching it over to a standard fork, but am concerned about the fact that looks like it would drop the front end down a couple of inches, with a resulting steepening of the head angle.

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Old 08-01-05, 12:44 PM   #6
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Quote:
Originally Posted by bkennedype
I am replacing the fork on my Cannondale road bike - headshok suspension and busted fork. Found a cane creek reducer for headtube that is a reducer and a headset - thank you freeranger for the advice on this - very nice actually - so now I can use 1 1/8 carbon fork and everything seems like it will fit nicely together. The measurements on the bike are as follows...7 inch head tube, 2 inches where suspension extends below the headtube, total 9 inches from top of headtube to top of fork. After I remove the headshok suspension it looks like I will be losing the 2 inches where the suspension will no longer exist...should I increase the steerer tube length above the headtube to compensate for this, and if so by how much. Or is another solution like an adjustable stem a better choice to get proper handlebar height. Thanks.
Those are not the only relevant dimensions. The key dimension you need to match is the distance from the fork's crown race to the dropouts. In the case of your headshock fork, you'll need to imagine where the equivalent of the crown race would be (somewhere under the boot, near the top) and measure from there.

It is not practical to build up a fork along the steerer to compensate for this, you need a "suspension compatible" model with longer blades. I'm not sure if such a thing exists that would be long enough, but it might be that some fork designated as a "29er" will have long enough blades, or possibly a cyclocross fork.

If you use a fork that's too short, it'll royally screw up the frame's geometry.

I would be nervous using a plastic fork for this even if you could find one with the workable geometry.

Sheldon "Good Luck!" Brown
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Old 08-01-05, 09:47 PM   #7
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Yea, Sheldon, as usual, managed to express clearly what I was trying to stumble out about the change in geometry. My hat's off to the man with an even better beard than mine.

Steve W.
WHO caught one of his cats killing a roll of handlebar tape today.
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