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Replace seat post?

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Replace seat post?

Old 02-15-20, 08:17 AM
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Replace seat post?

I sit my road bike in the trainer yesterday afternoon. Smacked the saddle with the palm of my hand and knock the top part of the carbon seat post loose. The bike is a 2.1 Trek Road Bike. I don't know the year. I believe the seat isa set back. How do I go about ordering the correct seat post. I don't believe I want to go back to carbo.
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Old 02-15-20, 09:47 AM
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Most post have the diameter printed on them. Find that or measure w/ calipers e.g. 27.2mm.

Is it broken , or did the parts come loose?
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Old 02-15-20, 10:08 AM
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Yep. Ascertain the diameter, estimate the setback. I always use thomson posts personally, but there are many many options from which to choose.
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Old 02-15-20, 10:33 AM
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I have a son-in-law with a 2.1 and i am sure there was a set back and it will surely be either a 31.6mm (~1 1/4") or 27.2mm (~1 1/16") so a ruler will tell you if you can't find the size stamp.
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Old 02-15-20, 03:19 PM
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One can always wrap a strip of paper around the post and mark the overlap point. Then measure with a good ruler and divide by Pi. But with any post replacement it's the actual fit that is the real determinate. Not all posts are made to labeled size.

BTW there's a possibility that the carbon post's top could be bonded back on. I've done a couple over the years with good results. Andy
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Old 02-19-20, 10:35 AM
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fwiw - if you wind up looking for a 27.2mm diamter, 300mm long unit with a 30.2mm Setback, I like my 2 bolt Velo Orange Grand Cru

Replace my seatpost
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