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Kicker of Elves
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427 Posts
Discussion Starter · #1 ·
Hey Gang,

Sorry if this shouldn't be posted in here and mods please move it if needed but I think you folks will be the most knowledgeable on this situation.

I have a Carver Carbon fork with an aluminum steertube, 1 1/8". It is butted at the bottom (not tapered, just thicker internally and externally) which gives a very tight tolerance in the lower headset cup.

The first fork was installed in a new frame that I didn't ream / face prior to installing and the lower cup gouged the steerer before I could get it back out. Shame on me, lesson learned, bought a new fork (Carver REALLY helped me out, thanks to Davis!).

I just back from a ride, unloaded the bike and noticed the headset wasn't spinning properly. Shear panic sets in, drop the fork out, and sure enough, another gouged steerer. I think the headset must have come loose, but I didn't notice it on the ride.

Anyway, sorry for the long story but is there any way I can mitigate the damage done to these steerers? I know the obvious answer (another fork) but dang, this thing only has a handful of rides on it.

Here's the first one:




Here's the second one, doesn't look as bad:




Thanks guys...be glad to hear your thoughts.
 

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Nemophilist
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1,873 Posts
Huh?

I'm not sure what is going on there at all. Never seen anything like that. If there is nothing sticking out inside the HT the race and bearing is seated, the star nut snugged, and the stem is tight, what can be the issue? Unless... You've got a frame gremlin. He lives in your DT and when you are riding he climbs up and holds a sharp metal object through the vent hole against your steerer, scoring it as you turn this way and that. When you take it apart to check, he escapes to the BB housing and has a wiz to rust your bearings.

Makes as much sense as anything else I can think of. Nobody can be THAT bad at installing a head set... can they?
 

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RCP Fabrication
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389 Posts
Cane creek head set? It's only happened to me once, and it was a cane creek head set, with a Ritchy carbon fork that the bottom inch of the aluminum steerer was butted larger.

You can see here, the "lip" on the cup. I don't know why it's there, but it caused the issue for me. I replaced the fork and put a king headset in.

 

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Kicker of Elves
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427 Posts
Discussion Starter · #5 ·
YES, in fact it is a Cane Creek. Just like that one! ^^^^

Thanks all for the replies, hopefully I'm on the right track now.
 

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Registered
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2,459 Posts
Clearly, Walt and Trailmaker, you guys aren't dumbasses like me (and possibly the OP). I did that about 4 years back and it was caused by a loose headset. The lower cup was quite thick where it pressed into the HT, so a little movement did exacty what the poor OP shows. Fortunately for me, I got Marzocchi to press in a new steerer.

Drew
 

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RCP Fabrication
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389 Posts
Just to throw it out there, when it happened to me the bike wasnt even ridden. I put the fork on, twisted the bars and could feel the slightest bit of rub. Pulled it apart and the fork was already ruined. While it *is* possible for a loose head set to cause the issue, I feel that you must have the worst case scenario already set up, a slightly oversized steerer AND a headset with a thick or "lipped" cup, or for the headset to be EXTREMELY loose.

IMO toss the cane creek.
 

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Nemophilist
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1,873 Posts
Wow...

I've never run across that. Never would have occurred to me even. Thanks for putting it out there. It's something we all need to be aware of. I for one don't have the cash to go replacing forks every week!

The next dumbass moment is only a breath away!
 

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Nemophilist
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1,873 Posts
To be Clear...

I've never paid attention to steerers before... really. You just set the crown race, put the bearing on, and slap it in the HT, right? What's to think about?

I'm sitting here thinking, what could be causing this? Couldn't be flex... could it? The steerer isn't bigger than others, is it?

So... the upper lip of that bearing cup is a smaller ID than the rest of it? (shakes head) Really? Even then... how can it be that close? ANY... ANY play at all in the bearing, and yur screwed?

Sheeesh.... :crazy:
 

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Registered
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689 Posts
It looks more like a case of the lower bearing cup being misaligned ever so slightly. The clearances from the steer tube to the race are probably idealized to a perfectly perpendicular mounting face. If you have some precise calipers available(or a shop close by) have the face measurements checked or faced.
 

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Registered
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439 Posts
Is it a new or freshly repainted frame?

I had an issue a couple of years back when a frame that had just been resprayed still had some blast media rattling around in it, and that got stuck between the headset cup and the steerer and did very similar damage. The cause was fairly obvious in my case because the headset was full of rusty iron filings, and the only other steel in the vicinity was the (new) stainless headset bearing (ally frame, ally steerer).

The company that did the paintwork (well respected frame builder/modifier) stepped up and sorted me out a new CSU.
 

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Registered
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2,459 Posts
JSYN, the headset I was using was a Cane Creek Tank II. Steel bottom cup, and very thick walled at that. There was ony a few mm clearance between it and the steerer. With those big ball bearing being loose, there was lots of play and consequently, scoring.

Drew
 
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