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Road Bike Seat Post sizes and questions

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Road Bike Seat Post sizes and questions

Old 08-31-12, 05:11 PM
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CanadianBiker32
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Road Bike Seat Post sizes and questions

For Getting a new seat post for my road bike

Do all seat posts diameter are same ?
i measured mine around 3.48 inches or 8.7 cm diameter around

Are all the same, or different

my present seat post is 2 bolts
i am thinking of going to a 1 bolt seat post, makes it simpler to adjust?

what is more recommended? 2 or 1 bolt seat post?
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Old 08-31-12, 05:28 PM
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Most of your questions can be answered in this recent short thread of mine. I would go to a 2-bolt quality seatpost, not a single bold or cheap. If you are careful, the less expensive ones recommended by some of the folks on this thread will work - but you have to be careful they stay tight. I did stay with the same brand of seatpost that stripped because it was a zero-dollar swap at my LBS (REI) and because I understand how the ridges stripped out. Now when I adjust, I check after about 100 feet for tightness, (yep, loosened a little) then after 1/4 mile, (very little) then a mile... and after about 5 miles.

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Old 08-31-12, 06:10 PM
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Originally Posted by CanadianBiker32 View Post
For Getting a new seat post for my road bike

Do all seat posts diameter are same ?
i measured mine around 3.48 inches or 8.7 cm diameter around

Are all the same, or different

my present seat post is 2 bolts
i am thinking of going to a 1 bolt seat post, makes it simpler to adjust?

what is more recommended? 2 or 1 bolt seat post?
Do you mean circumference? 3.5" diameter would be a pretty huge seatpost, like one you might find on a real fancy time trial bike.

I've used plenty of 1 and 2 bolt seatposts, and the 2 bolt seems better. Easier to adjust. Less likely to slip without using a ton of clamping force. It's not really a deal breaker either way though.
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Old 08-31-12, 06:36 PM
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Some 1 bolt posts do not microadjust. Instead they have splines, which give you a choice of a seat that it tipped up too far or a seat that is tipped down too far.

I like two bolt posts for their adustability.

Measure your posts' diameter with a good set of calipers. There are many different diameters and you need the right one, or a shim.
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