Minimum safe overlap Trek Seat Mast Domane

[dddd]

I'm finally out on the road on my Koppenberg edition "Domane", and feeling fortunate that the stack of this 56cm frame is sufficient for me.
But I seem to have reached a limit with the seat mast cap overlap onto the seat mast, which is only about two diameters even with a taller WTB Laser saddle on top.

I don't see any sort of minimum-insert line anywhere, so I don't know how far off I am from a safe perch for my 145lb mass. I'm using the shorter-offset, 135mm version mast, and with my saddle adjusted mid-way, so stresses are seemingly reasonable. But I'd rather know just how far that the mast is supposed to engage with the cap.

The optional mast cap is a longer 175mm iir, so if anyone here knows of a cheaper source for one, or would like to swap for my shorter/lighter 135mm round carbon mast, I'm all ears either way.

With it's short wheelbase, this Koppenberg is a hoot!

[benb]

Does the Koppenberg edition have height markings on the mast?

I know my regular Domane does, and IIRC the end of the markings is marked as minimum insertion?

I had to get the longer mast for mine, but I'm a freak.

[Motoguzzi1]

My team issue Koppenberg has the markings on the frame mast. I also use and need the longer seat mast cap.

[dddd]

Thanks for the replies(!), I got busy today when someone turned up wanting to buy the car I've been working on for the past 8 mionths, so only now am seeing all of this.

I was able to confirm that my seat mast has markings that I missed when I looked at it when it was still dirty. I was surprised to find that only 40mm of overlap is needed, which is far less than the traditional 2-1/2 diameters.
I had actually picked up a 175mm seat mast cap today between errands, then took it back for a refund when I realized that I had a full 50mm of overlap going on with my shorter original mast cap. Saved me well over a hundred dollars!

I also found that my IsoSpeed coupling had loosened, even with it's blue thread locker. So I re-did that with fresh blue LocTite and 7Nm of torque.

Looking forward to more manic fun riding this Koppenberg!

[Clean39T]

I have a longer cap in my spares bin. $50 if you do end up needing it...

Sent from my Pixel 2 XL using Tapatalk