How to fix a bike seat post in place?

June 15, 2006 7:29 AM

How can I fix my bike saddle to the correct position?

I made the mistake recently of picking my bike up by the saddle instead of the frame and the seat post came out. It went back in easily enough but now the saddle moves round - ie, the post revolves around so that the saddle faces sideways/backwards etc - far too easily. I can't see any way of tightening it - the only bolt is for the saddle rails at the top that deal with forwards/backwards tilt. sorry I don't have a digital camera for pics. any ideas?

posted by spiff101 to Sports, Hobbies, & Recreation (12 answers total)

If it's like most bikes, there's a bolt (or maybe a quick-release) where the seat post goes into the frame. That's the one you need to tighten.
posted by box at 7:32 AM on June 15, 2006

Best answer:
posted by handee at 7:46 AM on June 15, 2006 [4 favorites]

Great artwork handee - I second your recommendation. If that doesn't work, or is difficult to figure out (lack of appropriate tools, etc.) then perhaps spiff101 should take the bike to a shop - they'll probably adjust and tighten the post for free.
posted by sablazo at 7:53 AM on June 15, 2006

If it doesn't have a quick release mechanism, you'll probably need a hex wrench to tighten the bolt that handee pointed out.
posted by jtfowl0 at 8:29 AM on June 15, 2006

also, you can use a crescent wrench or adjustable wrench for that same bolt. you may need two wrenches - one to hold the bolt and one to tighten the nut.
posted by cubby at 8:59 AM on June 15, 2006

most succinct answer ever!
posted by randomstriker at 9:58 AM on June 15, 2006

Response by poster: thanks guys, particularly the awesome artwork..but my bike doesn't have the indicated bolt. The only bolt is where the post meets the frame at the bottom..and the problem is higher up, as in handee's pic. There's a kind of collar with a groove in it above where the post separates, but it doesn't screw down onto what look like screw-threads below where it separates. Or at least, I can't make it. Am i missing some kind of bolt or lever? I guess I'll get it to a shop eventually, it's just they're not open during weekends or lunch hours here.

I also altered handee's pic to show my seatpost - how do I post it?
posted by spiff101 at 8:16 AM on June 16, 2006

You need to put the pic on a website then include it here with an image tag - easy if you have a website and kow a little html. if you don't, email the image to me and I'll stick it up (my email's in my profile).
posted by handee at 8:22 AM on June 16, 2006

The collar that goes around the seat tube should have a bolt or a quick-release that spans the gap in the collar. It should have a nut that you use to tighten it down. It will not screw down against the seattube collar, which is not threaded. If you are missing the nut, you can buy a new seatpost bolt (measure the gap or the existing bolt first to get the right size) like this one for example.

Here is a picture of a seat post properly installed. You can see the seatpost bolt sticking out through the nut. It may be that on your bike the bolt goes through a collar that is not integral to the frame (as in the in the picture), but the idea is the same.
posted by Lazlo Hollyfeld at 1:51 PM on June 16, 2006

Response by poster: thanks Lazlo but the problem is not where the tube goes into the frame, but where the upper part of the tube goes into the lower.

I have now got a raised area hidden under the screw-down collar to go part-way into the groove...then the collar screws down a little, and it's possible to ride without the saddle moving round all the time; but it's still loose and it comes out very easily. any ideas? (see pic to be kindly posted by handee).
posted by spiff101 at 3:35 AM on June 20, 2006

Here it is!

I'm going to have to step back here because none of the bike seats I've seen look like that. (I checked four in my house before making this rash statement). What make is the bike?
posted by handee at 5:45 AM on June 20, 2006

Response by poster: specialized...I think it's called an 'endurance' or some such. it's a hybrid. no help that I can see on the specialized website.
posted by spiff101 at 6:19 AM on June 20, 2006