KCNC Expander Plug Issue

Discuss light weight issues concerning road bikes & parts.
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KH1
Posts: 1327
Joined: Thu Feb 19, 2009 3:40 am
Location: Mornington Peninsula

by KH1

My KCNC expander plug on the CAAD9 has been regularly coming loose causing play in the steerer. Has anyone else experienced the same or similar issues with this part?
What if any solutions might there be other than just going with something else?
Don't let the truth get in the way of a good story......
Argon
CAAD9 6.78Kg
Supersix 6.78Kg

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devinci
Posts: 3039
Joined: Sat Jan 03, 2009 9:43 pm
Location: Canada

by devinci

extralite ultrastar 2, does the job perfectly and is light as hell

by Weenie


em3
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Joined: Tue Dec 23, 2008 2:57 pm
Location: NYC

by em3

devinci wrote:extralite ultrastar 2, does the job perfectly and is light as hell



+1
______________

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djconnel
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by djconnel

+1

Sent from my ADR6300 using Tapatalk

lechat
Posts: 260
Joined: Thu Sep 30, 2010 3:32 pm
Location: S.E. TN

by lechat

The plug only loads the bearings. The stem keeps everything tight. If the stem is tightened correctly, you should be able to remove the plug. If you wish.

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djconnel
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by djconnel

But then if your stem comes loose on a ride, it's SOL. Never happened to me yet, but....

lechat
Posts: 260
Joined: Thu Sep 30, 2010 3:32 pm
Location: S.E. TN

by lechat

Yeah, i know. Wouldn't remove mine. Just saying that it's not his bung that's to blame. (or maybe it is).

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theremery
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Location: New Zealand

by theremery

carbon build paste between the stem and steerer. Use a torque wrench and a tiny amount of LOW STRENGTH (the yellow one???) loctite on the thread of the expander. Job done.
Some steerers MUST be run with the expander in place.......I'm not sure about your one tho.
Updated: Racing again! Thought this was unlikely! Eventually, I may even have a decent race!
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prendrefeu
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by prendrefeu

Not all steerer tubes accommodate the Extralite Ultrastar 2 though.

This past weekend 4 (FOUR!) forks I had on hand did not have an ID large enough to even fit the ultrastar in snuggly (before tightening).
Exp001 || Other projects in the works.

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KH1
Posts: 1327
Joined: Thu Feb 19, 2009 3:40 am
Location: Mornington Peninsula

by KH1

I might revisit the stem bolt tension. It could be that. Just never had this problem before mounting the KCNC. It has a weird tightening mechanism that requires the expansion part of the part to be adjusted before locking the whole thing in place - it seems to work okay during install but none of my other expanders have used this design. :noidea:
Don't let the truth get in the way of a good story......
Argon
CAAD9 6.78Kg
Supersix 6.78Kg

trikobe
Posts: 163
Joined: Tue Dec 16, 2008 9:16 pm
Location: Las Vegas, NV

by trikobe

Is the OD of the ultrastar vs the ultrastar 2 the same? Or is it just a modification of how it tightens that differs? Only reason I ask is because I couldn't use version 1 with my colnago C59 and for my caad10 I had to bring the dremel out to reduce the OD to get it to work

Ypsylon
Posts: 1403
Joined: Wed May 24, 2006 6:25 pm

by Ypsylon

I've used various KCNC expanders on different bikes and I can't remember one rattling lose, neither in carbon steerers nor in an aluminium one. I've always used dynamic paste when using it with cf.

Is the expander coming lose, or the bolt holding the top cap?
"Nothing compares to the simple pleasures of a bike ride," said John F. Kennedy, a man who had the pleasure of Marilyn Monroe.

bikejunkie
Posts: 157
Joined: Tue Jun 22, 2010 8:43 pm
Location: UK

by bikejunkie

I had the Kcnc one, it too kept coming loose so I ordered a Extralite Ultrastar 2 and haven't touched it once since It was fitted 7 months ago. very light yet stays in. soild. :D

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KH1
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Joined: Thu Feb 19, 2009 3:40 am
Location: Mornington Peninsula

by KH1

Ypsylon wrote:I've used various KCNC expanders on different bikes and I can't remember one rattling lose, neither in carbon steerers nor in an aluminium one. I've always used dynamic paste when using it with cf.

Is the expander coming lose, or the bolt holding the top cap?


To be honest I'm not sure. But every 5 or 6 rides I need to undo everything and re-tighten to stop the rattle in the steerer.
Don't let the truth get in the way of a good story......
Argon
CAAD9 6.78Kg
Supersix 6.78Kg

Ypsylon
Posts: 1403
Joined: Wed May 24, 2006 6:25 pm

by Ypsylon

I find that very strange.

Do you use carbon paste? How large is the gap between the spacer and the steerer?
"Nothing compares to the simple pleasures of a bike ride," said John F. Kennedy, a man who had the pleasure of Marilyn Monroe.

by Weenie


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