Loose seat stem housing on Trek Madone 9.2

[Bill S.]

Anyone know how to remove the plastic cover at the base of the seat stem housing on a Trek Madone 9.2? The housing piece for the seat stem wobbles a little and I'd iike to tighten it. Assuming there's a screw underneath the covers.

   
   

Thanks!
Bill

[Jesper]

(04-24-2021, 01:11 PM)Bill S. Wrote:  Anyone know how to remove the plastic cover at the base of the seat stem housing on a Trek Madone 9.2? The housing piece for the seat stem wobbles a little and I'd iike to tighten it. Assuming there's a screw underneath the covers.




Thanks!
Bill

Hello Bill and welcome,

That set-up is absolutely foreign to me. I thought those frames had the "iso" decoupler feature and that cover went over the works regarding that design. I know they made an adjustable "iso" version also. I would refer to your owners manual (or find a copy online) before making adjustments and trying to over-tighten something and cause damage. I'm sure Trek has torque specs for all of the hardware related to the frame itself. Quite often, plastic covers simply "snap" into place and are not held down by any hardware; they get loose from repeated removal due to stretching and wear. I have, in other situations, added a little rubber cement onto the cover where it engages and that usually eliminates any noise during use.
Regardless of what hardware that cover is hiding, I would only use a torque wrench for future tightening of same.

[ChaseCal]

Okay SO that part doesnt hide any harder where that would make the seat post loose in that sense, but it also adjusts that at the same time. So trek has this whole decoupler system called isoSpeed in the seat post and headtube to make the ride smoother. so focusing on the seat here, that cover is two parts. one is made of carbon and it is the outside piece, which just snaps off and on. after that, the rubber piece you are looking at has edges under it so it cant come up without taking that earlier carbon piece off. anyways, that loose feeling you have is the iso speed. the seat tube decouples from the top tube kind of. if you want to adjust it, take those two pieces off, unscrew the two screws under it with a 6mm and an 8mm, and then the other one or two crews maybe four or five inches under the seatpost, above the rear tire. you then have one screw left under the top tube where it looks like it holds two pieces together. unscrewing this allows you to freely move a slider on the piece that is attached to the seatpost. moving the slider closer to the headtube will make the ride softer and it decouples a bit more, which is usually where we put them when we build the bikes so they feel a bit better. if you want to stiffen this up you move the black slider towards the seat tube, and rescrew everything back together. if you need more info or a video that can actually show you instead of my rambling here is a pretty good link: https://pelotonmagazine.com/video/exploded-the-new-trek-madone-slr/

[Jesper]

(04-27-2021, 09:39 AM)ChaseCal Wrote:  if you need more info or a video that can actually show you instead of my rambling here is a pretty good link: https://pelotonmagazine.com/video/exploded-the-new-trek-madone-slr/

Thank you for that explanation. I was confusing that individual's problem anyways. I did not realize that the decoupler could make the seat post feel loose if not adjusted to a stiffer level. After riding standard steel frames all my life I might find it to be a bit disconcerting. I would think that the dealer would have made that apparent unless it was purchased used. I know I would tell a potential buyer about that feature and how to access and adjust if I were the seller.
Do you know of any examples where the decoupler has become 'loose' due to regular use wear or deterioration? I am also curious as to how those frames felt before the adjustable decouple was introduced.
Thanks again for taking time to set things right!

[Bill S.]

Thanks for that awesome response. I figured those two plastic pieces on each side just pop off, but they're on there pretty tight. They won't come off by hand and I'm hesitant to force them with a tool. Do they come straight off or should I pull them upward or toward the front or back? It'd be nice to see how they snapped on before getting too aggressive.

Thanks again!!!

Bill

(04-27-2021, 09:39 AM)ChaseCal Wrote:  Okay SO that part doesnt hide any harder where that would make the seat post loose in that sense, but it also adjusts that at the same time. So trek has this whole decoupler system called isoSpeed in the seat post and headtube to make the ride smoother. so focusing on the seat here, that cover is two parts. one is made of carbon and it is the outside piece, which just snaps off and on. after that, the rubber piece you are looking at has edges under it so it cant come up without taking that earlier carbon piece off. anyways, that loose feeling you have is the iso speed. the seat tube decouples from the top tube kind of. if you want to adjust it, take those two pieces off, unscrew the two screws under it with a 6mm and an 8mm, and then the other one or two crews maybe four or five inches under the seatpost, above the rear tire. you then have one screw left under the top tube where it looks like it holds two pieces together. unscrewing this allows you to freely move a slider on the piece that is attached to the seatpost. moving the slider closer to the headtube will make the ride softer and it decouples a bit more, which is usually where we put them when we build the bikes so they feel a bit better. if you want to stiffen this up you move the black slider towards the seat tube, and rescrew everything back together. if you need more info or a video that can actually show you instead of my rambling here is a pretty good link: https://pelotonmagazine.com/video/exploded-the-new-trek-madone-slr/

[ChaseCal]

They should pop kind up out and up, there's a bit that slides over the bolt. if you pop those off, the piece should be able to move freely. obviously, with the piece being carbon, you can break it so be weary...

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(04-27-2021, 12:28 PM)Jesper Wrote:  

(04-27-2021, 09:39 AM)ChaseCal Wrote:  if you need more info or a video that can actually show you instead of my rambling here is a pretty good link: https://pelotonmagazine.com/video/exploded-the-new-trek-madone-slr/

Thank you for that explanation. I was confusing that individual's problem anyways. I did not realize that the decoupler could make the seat post feel loose if not adjusted to a stiffer level. After riding standard steel frames all my life I might find it to be a bit disconcerting. I would think that the dealer would have made that apparent unless it was purchased used. I know I would tell a potential buyer about that feature and how to access and adjust if I were the seller.
Do you know of any examples where the decoupler has become 'loose' due to regular use wear or deterioration? I am also curious as to how those frames felt before the adjustable decouple was introduced.
Thanks again for taking time to set things right!

Yeah, I mean, to be honest, a lot of people forget about it. It is a feature that is prominent in a lot of our bikes starting at a certain level and I see the guys trying to sell them at our shop and they don't even mention it so frankly, I'm not all that surprised. I've never actually seen them come loose or at least no one has brought one into me saying it's loose yet. but as with any bolt, maybe toque it a bit every now and again. I've got to say too, these are very nice. They are quite stiff bikes so it was easy to get kind of beat up but you can set this thing to its softest setting and it's almost a suspension Seatpost. - so I get why you might think it's loose... but man it's comfy if you have it set to what you want.

[Jesper]

Thanks @ChaseCal !

[Bill S.]

Thanks Chase, but unfortunately my Madone doesn't have that decoupler. But I still think you're right, that those plastic covers on each side should pop off to allow access to the bolt I need to tighten. They just don't come off easy so was wondering if there was some sort of special tool or trick to it. Afraid of breaking a cover. Thanks again. Bill

(04-29-2021, 09:08 AM)ChaseCal Wrote:  They should pop kind up out and up, there's a bit that slides over the bolt. if you pop those off, the piece should be able to move freely. obviously, with the piece being carbon, you can break it so be weary...

---

(04-27-2021, 12:28 PM)Jesper Wrote:  

(04-27-2021, 09:39 AM)ChaseCal Wrote:  if you need more info or a video that can actually show you instead of my rambling here is a pretty good link: https://pelotonmagazine.com/video/exploded-the-new-trek-madone-slr/

Thank you for that explanation. I was confusing that individual's problem anyways. I did not realize that the decoupler could make the seat post feel loose if not adjusted to a stiffer level. After riding standard steel frames all my life I might find it to be a bit disconcerting. I would think that the dealer would have made that apparent unless it was purchased used. I know I would tell a potential buyer about that feature and how to access and adjust if I were the seller.
Do you know of any examples where the decoupler has become 'loose' due to regular use wear or deterioration? I am also curious as to how those frames felt before the adjustable decouple was introduced.
Thanks again for taking time to set things right!

Yeah, I mean, to be honest, a lot of people forget about it. It is a feature that is prominent in a lot of our bikes starting at a certain level and I see the guys trying to sell them at our shop and they don't even mention it so frankly, I'm not all that surprised. I've never actually seen them come loose or at least no one has brought one into me saying it's loose yet. but as with any bolt, maybe toque it a bit every now and again. I've got to say too, these are very nice. They are quite stiff bikes so it was easy to get kind of beat up but you can set this thing to its softest setting and it's almost a suspension Seatpost. - so I get why you might think it's loose... but man it's comfy if you have it set to what you want.

[ChaseCal]

Alright, so I'm guessing you have either a 2016 or early 2017 madone. trek didn't have that full iso speed yet, but that is still a decoupler in it, but it's not adjustable, or at least to my knowledge. that being said, its entirely possible its just loose. like the more current models, the covers are form fit so they are designed to pop off with enough pressure. Once you do you can tighten the bots under it and see if that is causing the issue. or just bring it into the bike shop and have them take it off and make them buy you a new cover if they break it.