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You be the judge: Tweaked or not?

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You be the judge: Tweaked or not?

Old 06-08-07, 12:07 PM
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You be the judge: Tweaked or not?

I just picked up these old Rock Shox Mags. Out of the box the hear tube angle didn't look parallel to the stancions, after instalation on the frame it was more pronounced.

I wrote the seller and this was his reply:

"Its called off set, or rake. Modern forks achieve the same effect by bringing the tubes forward at the crown, and then going down, where forks of this vintage 'raked' forward from the crown. The degree of which your headtube is set can exagerate this effect. A fork w/ a steeper head angle will make the fork more vertical, where if you have a relaxed headtube it will rake out. Another consideration is whether or not your have a suspension corrected frame. If you pur a suspension fork on a bike that never had one, the fork will rake more than it would have w/ the ridid fork. There are many factors to consider. Forks withstand substantial abuse, and a hard drop would have been absorbed by the suspension. Suspension forks dont bend out when experienced by a big hit, the frame will brake first. They are made to go up and down. It sounds like you have an early frame or a frame w/ obsolete geometry. Welcome to the world of planned obsolesence."


I've never heard of that being done. Offset at the axle or crown yeah, but not pitched out tubes!

Does he speak true and this fork is made differently or is he tring to feed me a line of bull?

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Old 06-08-07, 01:34 PM
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I don't think it's tweaked. That fork gets its offset from having the crown forward of the headtube and also by having the stanchions/lowers angled slightly forward relative to the steerer. The fork doesn't have its dropouts offset forward like most newer suspension forks, it needs the slight forward angle to gain offset...........I think the seller was telling you basically the same thing, but in a way that reeks of fluffy BS to me-
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Old 06-08-07, 01:39 PM
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I think if that fork had been damaged and bent like that, there would be evidence of it at the crown.
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Old 06-08-07, 01:42 PM
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Easy way is to measure the hole in the crown. If it's bored parallel to the steerer, then something's wrong with the fork tubes.

Excessive wear will allow the sliders to wiggle and rock over the stanchion tubes. Have someone hold front-end up and grab the fork sliders with your hands. Push back and forth, do you have any play?

Last edited by DannoXYZ; 06-08-07 at 08:54 PM.
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Old 06-08-07, 01:48 PM
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No slack in the bushings, the sliders are parallel with the stancions.

It's the head tube to stancion angle that gets me. Granted there is minimal offset between the steertuber bore and the stancion bore and there is no drop-out offset either. I guess it does make sense to kick angle there.
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Old 06-08-07, 03:23 PM
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From looking at the photo, there does appear to be a slight angle between the black line of the headset seal and top of the black cap on the stanchions... So about 15mm offset from the crown and another 30mm offset from the angled stanchions maybe?
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Old 06-08-07, 06:37 PM
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Thanks for the reassurance. I've never seen it done this way before.

Ya learn something new everyday.
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