Consenus Expander Plug Recommendation

Discuss light weight issues concerning road bikes & parts.
drainyoo
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by drainyoo

sugarkane wrote:3. Carbon paste should always be used as should Ti prep or good quality grease.


Where do you apply the carbon paste, to the inner walls of the steerer? Also, does Ti prep have any advantages over grease?

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sugarkane
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by sugarkane

on the contact points of the expander or the wall of the fork steerer with the carbon paste it doesn't mater which and personally i will always use Ti prep over grease on Ti or alloy bolts as my bike has no steel bolts and alloy is only mildly less reactive to galvanic corrosion than Ti so yea if you got it use the Ti prep, it holds the threads better and prevents more problems in the long run than straight up grease..

drainyoo
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by drainyoo

Thanks. So Ti bolts get Ti prep, all other bolts get grease. Check. Do you recommend a certain Ti prep.

Sorry for derailing the thread.

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sugarkane
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by sugarkane

Finish line ti prep is pretty darn good.
Awesome company's like ee cycle works give you Ti prep with your brakes..

And no all bolts should get ti prep if you have it.
Especially alloy bolts as when used In high salt environments like costal Australia they are just as bad as Ti bolts with galvanic corrosion.
If the bolt ain't steel, carbon or nylon then ti prep is your friend

drainyoo
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by drainyoo

Got it. I appreciate all the info.

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Stolichnaya
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by Stolichnaya

Nice assumption, Sugarkane, but, no, you would be wrong.
I used Extralite alu paste and it siezed anyway.
But your sarcasm is appreciated...

Wingnut
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by Wingnut

sugarkane wrote:And no all bolts should get ti prep if you have it.
Especially alloy bolts as when used In high salt environments like costal Australia they are just as bad as Ti bolts with galvanic corrosion.


Sorry?

Am I reading this correct...are you claiming Ti bolts get galvanic corrosion?

My understanding is that Calfee (head tube, BB and dropouts) and Colnago (BB) used Ti inserts due to the lack of expansion and galvanic corrosion?

Calfee Design - If metal must be used it should be titanium. Titanium, unlike steel and aluminum, is not susceptible to corrosion. Although a metal, it also has thermal expansion characteristics fairly similar to carbon fiber while aluminum and steel are quite different.

r_mutt
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by r_mutt

For some reason, 2 different mechanics whom have extensive knowledge, have moved my cannondale expander plug to 2 new bikes I've had lit up. Their explanation was that it was better. I left it at that.

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FIJIGabe
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by FIJIGabe

Actually, this thread has provided quite a bit of helpful insight. Other than Fairwheel, any other vendors sell the Ultrastar 2's in the US?

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rmerka
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by rmerka

Galvanic corrosion is caused by mixing metals, it's not the same as just oxidation (like rust). One type of metal becomes a cathode and the other the anode. If you mix Ti and Al then the Ti becomes a cathode and the Al the anode (which corrodes quickly) in the presence of an electrolyte (say...sweat or other salty water). Ti by itself is very resistant to corrosion but mixing is bad unless you put some prep on it and create a barrier between the two metals and to keep out a potential electrolyte. For reference here's a chart, the further apart the metals are, the more prone they are to galvanic corrosion.

Image

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sugarkane
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by sugarkane

Sorry wingnut I should have used the term dissimilar metal galvanic corrosion but yea.. Ti bolts and and alloy stem = trouble with out ti prep.. ;)

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sugarkane
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by sugarkane

And Stolichnaya have you used your bike a lot on a trainer or have a habit of sweating Heavy over the stem? Sorry for the sarcasm but unless the unit is exposed to a lot of salt given it's internal use seizing it would be pretty impressive.. Mines Ben in 4 diffenernt bikes and I once cut the steerer down with out removing it and nearly cut the thing in half

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Stolichnaya
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by Stolichnaya

Sugarkane, you are on the same thought I have.

The bike that had the Extralite compression plug is the same that now has the MCFK. It was used on the trainer but also outdoors as well in damp conditions. It was about three weeks after installation when I went to adjust the stem and realized the plug would not come out.
My only three guesses are:
- Sweat (and I sweat a lot)
- Manufacturing tolerances between the top and bottom portions of the plug
- small burr or shavings that I did not see when preparing the threads that stuck
Although having many parts from Extralite, I cannot imagine the last two being an issue.

I switched over to the MCFK and have used it with the same Extralite alu grease and for a longer period in similar conditions (with the same top cap and bolt - both Extralite) and it has not siezed - checked it last night to make sure.

Would I use the Extralite plug again, sure. I like Extralite stuff and Sergio is a great guy with a fine sense of style, customer service and design excellence. In all honesty though, the design of the Carbon Ti and the McFK plugs appeal to me more because of the bigger and grooved surface of the part. Seems like the surface is less invasive when tightening inside a carbon tube.

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