So I'm going to cut my carbon steerer 0.5mm below the top of the clamp.
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So I'm going to cut my carbon steerer 0.5mm below the top of the clamp.
Give me your predictions of doom.
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The issue is the potential of crushing the top of the steerer tube with clamp pressure.
Assuming that doesn't happen, what do you hope to achieve by cutting it there?
Assuming that doesn't happen, what do you hope to achieve by cutting it there?
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If he was cutting it below the pinch bolt, there may be cause for concern, but he asked about cutting below the top of the clamp. I'm assuming the pinch bolt is well clear of that.
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What type of pressure plug will be used? I would be more comfy if a bonded in place type was used. Andy.
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Why?
Why not just spacer it to fit.
Then when you sell it-you can sell it with a longer steerer tube-meaning it is worth more
and folks who want a more upright posture can get it without using other tricks
Yeah-don't see any advantage
some disadvantages
Why not just spacer it to fit.
Then when you sell it-you can sell it with a longer steerer tube-meaning it is worth more
and folks who want a more upright posture can get it without using other tricks
Yeah-don't see any advantage
some disadvantages
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But as for crushing the tube, it's pretty hard to envision with an expander plug wedged in there.
I'm not a big guy, so I'm confident I can totally get away with this. It's purely for aesthetics' sake, so call me a nutjob if you will...
My SOP has always been to see how much I can get away with, and IME the sky's the limit.
I almost certainly won't sell it. Cost me $0 anyway; a 2009 Specialized Tarmac Elite frameset with a slight bit of damage a few inches above the FD hanger.
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Last edited by Kimmo; 10-17-13 at 08:13 AM.
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+1, no pun, but you're cutting it too close. However is it's flush or marginally sub flush you won't be able to add a spacer above. Better to cut it sub flush by 2mm or so, so you have more compression room.
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I followed FSA instructions. I figured that they know more about it than I do.
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That will be fine, until its not fine, then just make sure you (or the guy you sell the bike to) has really good dental insurance. But worth it to save the 4 grams I guess...
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It's not for the sake of 4 grams or whatever, it's for the sake of aesthetics. I have no need for spacers under the stem, and I'm pretty sure I don't need one above it.
What's the worst you can see happening? Is the top of my steerer going to become cone-shaped and my stem going to fly off despite the compression plug and preload bolt? Sounds pretty far-fetched to me; I could maybe see it if there was a star nut instead of a compression plug.
All my life, I've had a similar response to much cautionary advice; so much of it sounds twice shy to my ears. I'm in the habit of proving that many such rules just don't apply to me, if they're not altogether unnecessary.
So yeah, I'll bet my smile on this, no worries. The fact it's just for the mere sake of aesthetics shows you my degree of confidence.
As for bearing preload, any gap has to be enough, when it's snug. I'm thinking I'll dremel off the 0.6mm step under the top cap to maximise the steerer length, since its purpose is redundant; the preload bolt holds it centered. While I'm at it, I'll put an internal chamfer on the top of the steerer and trim the upper bit of the compression plug so it sits flush.
This will totally be NBD, at least as far as a guy my size is concerned. And as for selling the bike, we're talking about a damaged carbon frameset that cost me $0 here...
(Supposedly) risking my own neck is one thing, but geez - what do you take me for, some kind of greedy arsehole?
What's the worst you can see happening? Is the top of my steerer going to become cone-shaped and my stem going to fly off despite the compression plug and preload bolt? Sounds pretty far-fetched to me; I could maybe see it if there was a star nut instead of a compression plug.
All my life, I've had a similar response to much cautionary advice; so much of it sounds twice shy to my ears. I'm in the habit of proving that many such rules just don't apply to me, if they're not altogether unnecessary.
So yeah, I'll bet my smile on this, no worries. The fact it's just for the mere sake of aesthetics shows you my degree of confidence.
As for bearing preload, any gap has to be enough, when it's snug. I'm thinking I'll dremel off the 0.6mm step under the top cap to maximise the steerer length, since its purpose is redundant; the preload bolt holds it centered. While I'm at it, I'll put an internal chamfer on the top of the steerer and trim the upper bit of the compression plug so it sits flush.
This will totally be NBD, at least as far as a guy my size is concerned. And as for selling the bike, we're talking about a damaged carbon frameset that cost me $0 here...
(Supposedly) risking my own neck is one thing, but geez - what do you take me for, some kind of greedy arsehole?
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Absolutely nothing untoward will happen. The risks of not having the fork extend beyond the top of the stem are greatly exaggerated.
What's important is the depth of overlap of the steerer in the stem. I suspect (no basis, just a suspicion) that some makers started insisting on the spacer above to counter fudging when folks wanted the stem higher than correct, and having the form end well more than the 2-3mm guideline.
What's important is the depth of overlap of the steerer in the stem. I suspect (no basis, just a suspicion) that some makers started insisting on the spacer above to counter fudging when folks wanted the stem higher than correct, and having the form end well more than the 2-3mm guideline.
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If you cut it exactly .5mm below the top of the stem and your top cap has exactly a .6mm lip you'll always be .1xxmm away from being able to adjust the play out of your headset. Put a thin (1.0-2.0mm) spacer on top and it'll be perfect.
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Modifications will be performed, metal will be removed, no warranties will apply.
Doubtless the following will ensue
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Follow the rules:
https://www.velominati.com/the-rules/
Rule #45 A maximum stack height of 2cm is allowed below the stem and a single 5mm spacer must always – always – be stacked above. A “slammed down” stack height is preferable; meaning that the stem is positioned directly on the top race of the headset.
https://www.velominati.com/the-rules/
Rule #45 A maximum stack height of 2cm is allowed below the stem and a single 5mm spacer must always – always – be stacked above. A “slammed down” stack height is preferable; meaning that the stem is positioned directly on the top race of the headset.
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Rules are for blind obedience by fools, and guidance of the wise.
Any rule that contains a term like 'always' or 'never' is likely to be viewed with the deepest suspicion by me...
And that list of rules is pretty tongue-in-cheek... or at least I hope it is.
Any rule that contains a term like 'always' or 'never' is likely to be viewed with the deepest suspicion by me...
And that list of rules is pretty tongue-in-cheek... or at least I hope it is.
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#19
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Get a nice CF spacer to go under the top cap. a Kevlar/Carbon blend-weave can be dyed in a color.
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Rules are OK for folks who blindly follow them.
For those of us who think, it's not the rule, but the reasoning behind it that counts.
I have yet to hear a good experienced (or solid theory) based justification for the spacer above rule.
For those of us who think, it's not the rule, but the reasoning behind it that counts.
I have yet to hear a good experienced (or solid theory) based justification for the spacer above rule.
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All I can think is that minus the compression plug (and perhaps even a bit with it), the steerer would be compressed into a taper, causing maybe extra load on the preload bolt or something?
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Sheldon Brown's bike info ~~~ Park Tools repair help
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Sheldon Brown's bike info ~~~ Park Tools repair help
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Before you get righteous, please take the time to read the "rules." I provided the link. They are completely tongue in cheek.
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Had a bit of trouble with the headset, sorted it by converting the drop-fit to a press-fit with stretched electrical tape, now the bike rides like a dream.
Blows my mind how it can ride so soft yet squirt so hard when I stand on it, broken seat tube notwithstanding (pun intended). I haven't had a plastic bike in fifteen years; they've come a long way.
The short steerer (countersunk with tapered expander plug lid):
And with the lip removed from the bottom of the top cap, that gap is plenty.
I had a bit of trouble with the expander plug slipping (the knurling was only 0.1mm proud) so that prompted me to go a bit nuts... I almost promised a masterpiece of removed metal in an earlier post but deleted the passage.
Blows my mind how it can ride so soft yet squirt so hard when I stand on it, broken seat tube notwithstanding (pun intended). I haven't had a plastic bike in fifteen years; they've come a long way.
The short steerer (countersunk with tapered expander plug lid):
And with the lip removed from the bottom of the top cap, that gap is plenty.
I had a bit of trouble with the expander plug slipping (the knurling was only 0.1mm proud) so that prompted me to go a bit nuts... I almost promised a masterpiece of removed metal in an earlier post but deleted the passage.
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Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list