Trek domane/emonda seat mast cap - weight weenie clamp
Moderator: robbosmans
Hey WW's
Is there anyone here familiar with the trek seat mast cap and has replaced the actual tube clamp with something else?
I saw a nice looking picture of an emonda seat mast cap (seems to fit domane) but with a carbonice clamp instead of the standard clamp. I wonder if the tube had to be cut and shortened above the original clamp to do this.
I tried removing the clamp from the seat mast but it's really stuck there.
Is it glued on or what? Thanks for any input..
I measured the diameter of the mast to 34.3-34.5mm and thus a 34.9mm clamp should fit although not perfectly. There are cheap clamps out there at around the 10gr mark.
/a
Is there anyone here familiar with the trek seat mast cap and has replaced the actual tube clamp with something else?
I saw a nice looking picture of an emonda seat mast cap (seems to fit domane) but with a carbonice clamp instead of the standard clamp. I wonder if the tube had to be cut and shortened above the original clamp to do this.
I tried removing the clamp from the seat mast but it's really stuck there.
Is it glued on or what? Thanks for any input..
I measured the diameter of the mast to 34.3-34.5mm and thus a 34.9mm clamp should fit although not perfectly. There are cheap clamps out there at around the 10gr mark.
/a

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What you saw is the SLR 10 seat mast cap that Trek makes. They are 92g in the 175 length and 70g in the short.
And yes, those collars are glued on, which I’m not really fond of. I would much rather those collars be able to move so as you tighten them it provides a more uniform force around the entire tube, as if you were tightening a rope around it, versus a “clamping” effect. I think they’re just glued on to ensure they stay in that relative position since the glue seems to be really just a dab at some spot versus having been carefully applied all the way around.
Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ
I'm thinking to simply cut the mast just next to the clamp. The slit is long enough to use after, unchanged.
Then just put a generic 10gr 34.9mm clamp on the mast instead.
I could save like 20gr maybe. Smart or foolish?
I have the short seat mast. Cutting 15mm off it won't affect it I think. What do you think?
/a
Then just put a generic 10gr 34.9mm clamp on the mast instead.
I could save like 20gr maybe. Smart or foolish?
I have the short seat mast. Cutting 15mm off it won't affect it I think. What do you think?
/a
Personally I would leave it as is. Two places I have no desire to skimp on function and strength are skewers and seatpost clamps.
Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ
I was thinking the same and bought a 10g clamp; that was before I discovered the existing clamp was glued on. I may cut it off as well.I'm thinking to simply cut the mast just next to the clamp. The slit is long enough to use after, unchanged.
I also replaced the stock "ears" that grab the seat rails with ones I got on ebay with a titanium bolt. Shaved a few grams and the ears worked with the 7x10 rails on my new saddle.
If you do cut the mast please let me know how it went.apctjb wrote: ↑Sun Dec 24, 2017 2:42 amI was thinking the same and bought a 10g clamp; that was before I discovered the existing clamp was glued on. I may cut it off as well.I'm thinking to simply cut the mast just next to the clamp. The slit is long enough to use after, unchanged.
I also replaced the stock "ears" that grab the seat rails with ones I got on ebay with a titanium bolt. Shaved a few grams and the ears worked with the 7x10 rails on my new saddle.
The bike I'm working on is not mine and the owner decided to wait a little. Maybe later..
I'm curious to know what the weight of the clamp + 10-15mm of the mast actually weighs. What's the benefit sort of speak.
Thanks for writing
/a
I saw a picture comparing weights of the seatmasts and if a standard was 150gr the slr at the same length was only at around 130-140gr. I expected something lighter.
This 97gr figure intrigues me. In any case the seatmasts are very hard to come by so I guess it's modify time
for ww frames.
This 97gr figure intrigues me. In any case the seatmasts are very hard to come by so I guess it's modify time

So the clamp of that seatmast topper was removable? I've wondered how the flange would work, but apparently not large enough to keep the fully opened clamp?Fisherfreerider wrote: ↑Fri Dec 22, 2017 4:15 pmWhat you saw is the SLR 10 seat mast cap that Trek makes. They are 92g in the 175 length and 70g in the short.
https://www.youtube.com/watch?v=Wqd57CKeMvg
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This guy made his own:
https://weightweenies.starbike.com/foru ... 0#p1145932
https://weightweenies.starbike.com/foru ... 0#p1145932
I have (had?) the original seatmast clamp on my old Madone, and switched to the Emonda SLR version several years ago. The weight saving is 4g from one to the other.
Madone 9 - https://bit.ly/2Nqedbn
Emonda SLR - https://bit.ly/2UK5FP8
Crockett - https://bit.ly/2Xem4sk
Emonda SLR - https://bit.ly/2UK5FP8
Crockett - https://bit.ly/2Xem4sk
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I'm tempted to contact Mcfk or Darimo to see if they'll make one - if enough of us are interested it could work out ok cost-wise...

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