Steer-tube expander plug
#1
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Steer-tube expander plug
Can someone direct me to where I might find an extended expander plug for the '21-22 Trek Emonda? I contacted Trek and they said they don't produce such an item, and I haven't found any aftermarket options. This model of Emonda seems to have a proprietary expander plug shape, due to the inner shape of the steer tube.
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According to these instructions:
https://trek.scene7.com/is/content/T...L_SLR_USEN.pdf
You need one of these ordinary round expander plugs:
https://trek.scene7.com/is/image/TrekBicycleProducts/BontragerHeadsetExpanderPlugandTopCap_26266_A_Primary?$responsive-pjpg$&cache=on,on&wid=1440&hei=1080
As shown in this photo:
https://trek.scene7.com/is/content/T...L_SLR_USEN.pdf
You need one of these ordinary round expander plugs:
https://trek.scene7.com/is/image/TrekBicycleProducts/BontragerHeadsetExpanderPlugandTopCap_26266_A_Primary?$responsive-pjpg$&cache=on,on&wid=1440&hei=1080
As shown in this photo:

#5
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Thanks, but I I found that diagram previously. I don't see where in the instructions that it says a regular expander plug can be used. The internal shape of the steer tube is not round; it's more like a rounded triangle. It comes with a propriety plug; it's unique to this specific bike.
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Wait, what? Trek does not produce a compression plug that's not round and that they put factory on their bikes and were unable to help? 
How the hell does it end up in there then? Trek:

How the hell does it end up in there then? Trek:

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Thanks, but I I found that diagram previously. I don't see where in the instructions that it says a regular expander plug can be used. The internal shape of the steer tube is not round; it's more like a rounded triangle. It comes with a propriety plug; it's unique to this specific bike.
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Thanks, but I I found that diagram previously. I don't see where in the instructions that it says a regular expander plug can be used. The internal shape of the steer tube is not round; it's more like a rounded triangle. It comes with a propriety plug; it's unique to this specific bike.
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FYI, I found on weightweenies what looks like the Emonda with its expander plug:

Sure enough, it's not round.
Why make a not-round steer tube, Trek?

Sure enough, it's not round.
Why make a not-round steer tube, Trek?
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FYI, I found on weightweenies what looks like the Emonda with its expander plug:

Sure enough, it's not round.
Why make a not-round steer tube, Trek?

Sure enough, it's not round.
Why make a not-round steer tube, Trek?
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#13
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I decided to cut the steer-tube since no such extended plug exists. Trek also requires the use of their proprietary stem- or so I found out. I brought my bike in to have the steer tube cut and they saw my zipp sl speed stem (cf). They told me I have to use a Bontrager stem, otherwise I risk the possibility of sheering it off. The Bontrager stem bolts at an angle. According to them it spreads the clamping load. They told me a story about a co-worker that it happened to, and that Trek has issued a notice concerning the matter.
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I decided to cut the steer-tube since no such extended plug exists. Trek also requires the use of their proprietary stem- or so I found out. I brought my bike in to have the steer tube cut and they saw my zipp sl speed stem (cf). They told me I have to use a Bontrager stem, otherwise I risk the possibility of sheering it off. The Bontrager stem bolts at an angle. According to them it spreads the clamping load. They told me a story about a co-worker that it happened to, and that Trek has issued a notice concerning the matter.
Welcome to proprietary design.
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I decided to cut the steer-tube since no such extended plug exists. Trek also requires the use of their proprietary stem- or so I found out. I brought my bike in to have the steer tube cut and they saw my zipp sl speed stem (cf). They told me I have to use a Bontrager stem, otherwise I risk the possibility of sheering it off. The Bontrager stem bolts at an angle. According to them it spreads the clamping load. They told me a story about a co-worker that it happened to, and that Trek has issued a notice concerning the matter.

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