PersephoneDown

I bought a brand new 2020 Trek Domane SL6 in March. As with many new bikes, the saddle that came with it was pretty unbearable and so I bought a new one and installed it myself. The Domane has 2 bolts to adjust the saddle - one that tightens the clamps to the saddle rail and another one that handles angling the saddle up or down. This second bolt is supposed to be able to be loosened to do the adjustment, but upon further inspection, it seems someone put Loctite on it and I cannot loosen it at all! Why would a brand new bike have Loctite on one of the saddle adjustment bolts? What can I do to fix this?

HillRider

Did you loosen the clamping bolt before attempting to change the tilt adjustment bolt?

Andrew R Stewart 

As the hardware has gotten smaller and torque specs got tighter (as in min/max range) more and more bolts are coming with a thread locking compound on them. That and when a personal injury lawyer asks the bike designer if there's anything more that could have been done to keep the bars from slipping and spilling the client onto the road (at some high speed) and the engineer says "no" and then the lawyer asks why no thread locker was applied during the component's manufacturing... Andy

PersephoneDown

I did not. According to the service manual, the bolts should work independently of one another. I can't post the URL to it since I have not made 10 posts to the forum yet. I'm more of a lurker :-) But if you search for the Trek Domane service manual, the images in question are under 1. Install Common Components: Image #6 and Image #7 .

HillRider

I've worked on. a lot of two-bolt seat posts and all of them required loosening the clamp bolt before adjusting the tilt bolt or both bolts worked in opposition and both had to be tightened in sequence to hold the saddle position firmly.

WizardOfBoz

Can you post a link to the manual you are referring to? The 2020 Domana manual I found has two pinch bolts controlling seat tilt, and one bolt through the center of a circular piece to which the seat bolts to. Is that what you have?

I think I can say that Trek's documentation is, to my mind, a cluster f***. I love my Domane. Won't buy another Trek because their documentation is so poor. It's that bad.

fietsbob

One problem Mr Campagnolo had with his 2 bolt seat posts was people stopped using Brooks team pro saddles..

they were a perfect match... Tullio's Wrench even included an open end for the tension nut on the saddle nose
& an offset box wrench for the bolt heads on top of of the seat post..

HillRider

Yes and this was a "feature" that was absolutely baffling. What was the designer thinking?

fietsbob

before then, they used tubular seat posts & saddle clips .. that combination has continued to be offered, to this day..

<C> # 771 wrench , # 1044 seat Pin (#4051 'Super Record' was fluted) & the Brooks Team Pro leather saddles worked perfectly together..


There have been many other companies making their own designs as well as making the same style as <C>.. Zeus just one evample..

rydabent

Might make a difference on what color lock-tite was used.

WizardOfBoz

So the picture of the seatpost from that manual is below, and the figure 6 and 7 you refer to is also. From what I see you have TWO pinchbolts (green dots) to fix the seat angle, and one bolt (red dot in one pic, colored red in the picture labeled 6) underneath the pinch bolts to adjust that angle.

In picture 7 you have the bolt that fixes the seat rails to that rotating part of the post. It goes through the center of that rotating part.

The process, as I grok it, would be to install the seat and adjust it so that its' properly placed front to rear. Tighten the bolt as shown in picture 7.

To get the angle right, loosen both pinch bolts (green) and then adjust the angle with the red bolt in picture 6. Then tighten both pinch bolts. Use a torque wrench if possible.

I suppose you could locktite the pinch bolts (with BLUE (medium strength) and not RED (permanent) loctite) but with two pinchbolts that strikes me as overkill. Especially if you torque. And the instructions don't mention Loctite.