Creaking seat/post depending on saddle height
 

I am having a creaking seat (post) issue. It's an aluminum post in an aluminum frame.

I'm 100% sure it's coming from the seat - does't occur when I'm standing, and I can force it by wiggling my butt on the seat when not pedaling.

I've tried cleaning, greasing, tightening all the usual spots... seat post, seat tube, qr clamp, seat rails, etc.

It's a mountain bike, and I'm trying to slowly lower my saddle to help me on descents and big drops. The creak only occurs when I lower the saddle beyond a certain point. If it's raised... no creak. The difference between the no-creak and creaking height is only ~ 1 cm.

Driving me nuts! Any help is appreciated!

Cut 1cm off the bottom. Or more, depending on how much excess there is.

My thoughts exactly. I think that the seat post is hitting the seat tube at the very bottom of the post. I was going to do it yesterday, but didn't have a file to clean up the cut. I'll try tonight and report back.

Thanks!

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...there are saddle designs that develop creaks as well. Have you tried dropping a few drops of light oil or Triflow into the spots where the saddle rails insert into the plastic frame of the saddle ?

I just spent some time running down a creak and it tuned out to be in the stem/steerer tube interface. I was certain while riding it was the saddle. Good luck.

If the saddle is creaking, you may be able to reproduce it while off the bike.

It is possible that lowering the seatpost just changes your weight distribution and is a red herring.

I just located a recent creak on my bike to the seatpost area myself. By grabbing the nose of the saddle, and the rear of the saddle, and up/down motion, I can make the noise. Rocking the saddle, lengthwise, like it would be under load (the creaking/ping is on cracked roads).

Wondering about removing the post, greasing and reinstalling. Not sure if it is the seat or the post, but it sounds like the post, the way it pings.

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...I just start greasing and oiling the different material interfaces until the noise goes away. Greasing the post and saddle rail interfaces with the frame and seat clamp are good places to start.