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Bottecchia Seat Tube Issue?

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Bottecchia Seat Tube Issue?

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Old 01-06-18, 03:25 PM
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crandress 
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Bottecchia Seat Tube Issue?

I finally got the seat post out of my Bottecchia and could see a little lip protruding from the tip seat tube lug. I assume this is the seat tube. Is this indicative of an issue or just slight misalignment between the lug and seat tube? Maybe this is normal and I never noticed on my other bikes.

Also, the seat post was shockingly long. What should be the normal length of a seat post on a smallish road frame? This on was 193mm above the minimum insertion line.

What is your assessment? Thanks in advance.

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Old 01-06-18, 03:48 PM
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Could be a shim. Can you see a lower edge inside the seat tube?
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Old 01-06-18, 04:02 PM
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Chris, the quick way to tell if it's just the seat tube not cut flush with the top of the seat lug is to use a caliper to measure the seat tube below the seat lug and that short extension above the seat lug. If the O.D. is the same, it's just the seat tube not flush with the top of the seat lug.

The weight of the rider is a consideration in having a lot of seatpost showing above the seat lug since the bending moment is greater the greater the length of the seatpost between the lug and the saddle. If there's a lot of seatpost showing (more than six or eight inches) to get a reasonable fit on a small frame, get a bigger frame.
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Old 01-06-18, 05:03 PM
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Thanks guys. Sorry, I had measured and yes, the tube is the same diameter above as below the lug. And there certainly is no insert. That is what I thought originally. I was wondering if it was indicative of a failing lug. Or if this not uncommon. Nothing seems loose or wiggly.

As far as the seat post, I certainly do NOT need an extensive amount of seat post. In fact the bike is probably a touch big, so I need less. Seems like an excessively long seat post since most of it is inside the tube. Even when I purchased it was not too high. I was shocked at how much seat post was inside.

Unless anyone else has a different take, I assume this is just normal and there is no problem riding as is. The seat post I am certain is too long, I can use it, but will look for a shorter one. It is a smaller diameter than any of the ones I have at 26.2mm. Funny, the Atala I just bought has the same diameter and I plan to get a new seat post for that one too. So I will be on the lookout for two. Seems Campy did not make too many of that size, which would be my preference. We will see what I can find at the Madison bike swap next week. Maybe I will get lucky!
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Old 01-06-18, 05:56 PM
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Originally Posted by crandress
Thanks guys. Sorry, I had measured and yes, the tube is the same diameter above as below the lug. And there certainly is no insert. That is what I thought originally. I was wondering if it was indicative of a failing lug.
If it's not a shim, it probably just means the seat tube was trimmed slightly above the top of the seat lug. In most cases, the builder would file it down flush, so it doesn't project, but it's not a a structural concern. It just looks unfinished.
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