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eminence grease
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Discussion Starter · #1 ·
I have 4 Campy seat posts, two CF and two Ti. Three of the four use the traditional aluminum plates while the fourth uses the "upgraded" CF and black anodized plates. The latter also has the smaller .5mm pitch between knurls.

The CF plates slip. Plain and simple, I go over a speed bump, they ratchet one knurl backwards. Long ride, multiple bumps, completely changed angle by the time I get home.

I've tired a few things - roughing up the surface, hair spray to make them stickier, etc. I even broke down and read the instructions and torqued the thing (with a torque wrench) to the proper setting. And that lasted the longest, but again - slip, slip, slip.

Anyone else seen this? If so, did you find a magic fix? I was about to order the replacement plates in aluminum, but the combined cost for the three parts is $90, in which case I may as well buy a new post that doesn't slip.

Any ideas - greatly appreciated.
 

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Greased threads?

terry b said:
I even broke down and read the instructions and torqued the thing (with a torque wrench) to the proper setting. And that lasted the longest, but again - slip, slip, slip.
By chance, have you greased the threads on the clamp bolt? Without grease, you are not getting the full torque specified.
 

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Kant phuckin sphell
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Just ride one of your other bikes! :)

Seriously, I do not own one of those posts (so I am not sure of the design), but is it possible that if it was not torqued right the first time and then slipped it has worn the "ratchet" surface so it will not grab effectively now that it is properly torqued?
 

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eminence grease
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Discussion Starter · #4 ·
Kerry Irons said:
By chance, have you greased the threads on the clamp bolt? Without grease, you are not getting the full torque specified.
No grease. And 22NM takes a bit of cranking on the wrench. It certainly could be that I'm not hitting the correct torque, but I'm pushing far further than I would normally go on my other 1 bolt posts, including the other Campys.
 

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eminence grease
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Discussion Starter · #5 ·
the bull said:
Just ride one of your other bikes! :)

Seriously, I do not own one of those posts (so I am not sure of the design), but is it possible that if it was not torqued right the first time and then slipped it has worn the "ratchet" surface so it will not grab effectively now that it is properly torqued?
Is certainly possible. I think they did a dumb thing going from 1mm pitch on the knurls to .5mm. They are darn small. Might very well have worn what little there was off with a couple of slips.
 

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Every little counts...
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I've used Chorus Carbon in .5mm pitch. No problems at all. Just order the bottom plate in Al from the Chorus line to replace.

Also, take a wire brush and clean the knurling so that there isn't any dust or grime in the grooves. Degrease the contact areas with alcohol.

I have an older Chorus Ti post, it is nice too. But I really like the .5mm pitch. Alas, new bike has a Selcof Monocoque Carbon...this is a VERY nice unit.
 

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eminence grease
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Discussion Starter · #7 ·
Spunout said:
I've used Chorus Carbon in .5mm pitch. No problems at all. Just order the bottom plate in Al from the Chorus line to replace.

Also, take a wire brush and clean the knurling so that there isn't any dust or grime in the grooves. Degrease the contact areas with alcohol.

I have an older Chorus Ti post, it is nice too. But I really like the .5mm pitch. Alas, new bike has a Selcof Monocoque Carbon...this is a VERY nice unit.
Thx. I'll try the wire brush and if it doesn't do it - the bottom plate alone.
 

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you might try turning the top plate 180 and retorque...
fwiw, since i went to a "micro adjust" two bolt post, no prob in this dept..


terry b said:
I have 4 Campy seat posts, two CF and two Ti. Three of the four use the traditional aluminum plates while the fourth uses the "upgraded" CF and black anodized plates. The latter also has the smaller .5mm pitch between knurls.

The CF plates slip. Plain and simple, I go over a speed bump, they ratchet one knurl backwards. Long ride, multiple bumps, completely changed angle by the time I get home.


Any ideas - greatly appreciated.
 

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It may be too late...

once you allow a seatpost to slip, especially for an extended period of time, it will round off the peaks of the knurled portion of the seatmast. This allows the angle of the saddle to change more easily.
 

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eminence grease
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Discussion Starter · #12 ·
nocwrench said:
once you allow a seatpost to slip, especially for an extended period of time, it will round off the peaks of the knurled portion of the seatmast. This allows the angle of the saddle to change more easily.

Kinda hoping that's not the case, it's only slipped a couple of times. But consistently. The bike doesn't get ridden that frequently, so it's not as though I've allowed this to happen interminably over the past year. But, we'll see. I cleaned it up and torqued it to the max Campy recommends and now we wait.

Thanks to all for the suggestions.
 

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terry b said:
Of course, that's the first place my mind went - but what seatpost would I use? ;)

Get one of those Time frames that come with the seatpost... ;)

Seriously though, I've used that same post before with my saddle slammed all the way back and I never had that problem. Unfortunately I don't have any great insight to offer on this I'm inclined to think you just might not be hitting the right amount of torque like I've noticed others mention.

**** luck.
 

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nocwrench said:
once you allow a seatpost to slip, especially for an extended period of time, it will round off the peaks of the knurled portion of the seatmast. This allows the angle of the saddle to change more easily.

I'm thinking the same possibility. I'm sure a replacement plate must be available and if terry wants to be conservative I'm sure the alloy Chorus plate would work fine.
 

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terry b said:
Of course, that's the first place my mind went - but what seatpost would I use? ;)
I'm glad you asked, and, yes, I'd be glad to help you spec your next frame for a reasonable fee. Below are some distinctive seatposts guaranteed to compliment your next frame. Not only are they attractive, but they also perform as well as they look. You'll note that a couple of them have very positive saddle mounting systems that insure your saddle does does not slip.
 

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uni seats are back!

www.bergdesign.net/uni_seats.htm

devoid of problematic adjustment, these rock!
at 140 g. i do not know how the weight weenies can resist.

alienator said:
I'm glad you asked, they look. You'll note that a couple of them have very positive saddle mounting systems that insure your saddle does does not slip.
 

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alienator said:
I'm glad you asked, and, yes, I'd be glad to help you spec your next frame for a reasonable fee. Below are some distinctive seatposts guaranteed to compliment your next frame. Not only are they attractive, but they also perform as well as they look. You'll note that a couple of them have very positive saddle mounting systems that insure your saddle does does not slip.

Wow! Those are beauties...
 
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