# Madone Seat mast



## tgrider (Jul 5, 2010)

I have a 2010 madone 5.5. The seat mast is at the lowest possible level on the frame. Are there different lengths available or is this a single size? The one I have is around 6.5" from the seat rail to the bottom of the mast.


----------



## jellis25 (Oct 6, 2009)

There are two sizes, a 120mm and a 160mm. Sounds like you have the 160mm as 6.5in is about 165mm. 

You can buy it here or go to your lbs and see if they have any available. You may be able to swap yours out if they are nice. Good luck.


----------



## tgrider (Jul 5, 2010)

Saw that, but it said 2008. Called customer service to ask if that would work on mine and stayed on hold for an hour, had to hang up to go into a meeting, never got to speak to anyone. LBS I bought the bike from isn't the most knowledgeable. They pushed the cap beyond the mark that says don't go past this mark. They only work with the lower end of Trek and Giant's lineup.


----------



## jellis25 (Oct 6, 2009)

It will work for you 2010 5.5. It is the 2008 generation madone which includes the 2008-2010 5-series and 2008-2009 6-series. I owned a 2010 5.5 as well so I am familiar with the bike. I also work in a trek shop.


----------



## tgrider (Jul 5, 2010)

Thanks


----------



## Trek2.3 (Sep 13, 2009)

I bought a 120 mm seat mast cap on Ebay last week for $25. Always look there first.

They actually come in a variety of sizes. I've see 120mm, 130mm, 140mm, 160mm and 175mm. I've had all of them at some time and measured them with a steel tape measure. Not all of the sizes are in Trek's catalog but they are all out there on bikes and on Ebay.


----------



## tgrider (Jul 5, 2010)

Thanks,through this I have learned it is the mast cap I am looking for, not the mast.


----------



## lucascarvajal (Apr 10, 2010)

Trek2.3 said:


> I bought a 120 mm seat mast cap on Ebay last week for $25. Always look there first.
> 
> They actually come in a variety of sizes. I've see 120mm, 130mm, 140mm, 160mm and 175mm. I've had all of them at some time and measured them with a steel tape measure. Not all of the sizes are in Trek's catalog but they are all out there on bikes and on Ebay.


You are wrong!!! only 2 sizes. you may be talking about a seatpost.


----------



## Rider07 (Feb 25, 2007)

*Mast cap*

My seet needed to go down about 1/2" more. Shop gave me the smaller cap, but after looking at the original I noticed there is a foam ring inside the post that was keeping it from moving into the lower position I needed. I removed the foam and was good to go.


----------



## Trek2.3 (Sep 13, 2009)

lucascarvajal said:


> You are wrong!!! only 2 sizes. you may be talking about a seatpost.


*No. * I am correct. They may sell only 2 seat mast CAPS as replacement parts *but they MAKE them in all the sizes I listed*. 
Or . . . Trek's quality control re these "minor" parts really sucks (I think this is part of the problem).


P. S. The 2008-10 teardrop seat mast caps have a ridge of excess carbon fiber at the top of the inside about 1/2 cm down. If you knock that off, the cap will go down another 5mm.


----------



## kidcyclist (Jan 30, 2014)

If you still have your longer seatpost, can I buy it off you? I need a 160 mm or 175 mm. The longer, the better


----------



## JCT_NC (Jun 19, 2010)

Trek2.3, you're not entirely accurate about the mast cap sizes offered, but that's understandable since Trek has listed the sizes differently depending on where you take your measurements from.

It also doesn't help that the two sizes of teardrop caps were referred to as 160/120, where the round caps are referred to as 175/135. Still just "tall" and "short," though.

For both the teardrop (2008-2010) and current round mast caps, there have only ever been the two sizes (tall and short). The teardrop caps were offered in 3 offsets (-20, -5, +10) and the round caps are offered in two offsets (-20mm and -5mm). No need to offer a positive setback on the round cap, since you can just flip it.

Here's a post from Trek showing the two sizes on the teardrop style: Up The Road: What size Madone should I get?


----------

