Dropper post keep sinking

[Oddy72]

Why does my dropper post keep sinking when I’m sat on it ? And before you say it …. I’m not 25 stone!! Biked 3 week old . It’s not hydraulic, it’s a cable one . Any suggestions on a fix . Cheers

 

[Jackware]

Cable too tight?

Try adjusting the tension at the lever end?

 

[Oddy72]

Cable too tight?

Try adjusting the tension at the lever end?

Will give that a try mate , thanks

 

[JP-NZ]

Why does my dropper post keep sinking when I’m sat on it ? And before you say it …. I’m not 25 stone!! Biked 3 week old . It’s not hydraulic, it’s a cable one . Any suggestions on a fix . Cheers

Its likely a leaky air cylinder, remove the seatpost and check the pressure at the bottom. If it is leaking then its likely warranty

 

[Stihldog]

As suggested, It could be the cable tension, it could be low pressure, or the piston has failed (like an office chair). Some droppers are hydraulic actuated from the lever. (ie. Sram Reverb). Some have a hydraulic piston inside …which can fail. A slowly dropping dropper will get progressively worse if this is the case. This happened to one of mine.
Do you know the make of dropper?

 

[Landy Andy]

Mine just needed striping, cleaning, and some lubrication.

 

[Oddy72]

so I put pressure in the seat with it locked out this morning, slowly sank, I turned the adjuster at the lever maybe 1/4 of a turn , put pressure on again and seems to not budge.
time will tell I guess on the next ride out. It’s a “ONOFF” dropper by the way, only 3 weeks old

 

[Tim1023]

Top tip if you're going to be working on your dropper, particularly where the dropper attaches to the cable: shove a tissue down the seat tube around the cable whilst you're working. There may well be a tiny grub screw holding the cable retainer clamped to the cable. You REALLY don't want to drop that down into the frame!

Picture credit: Quick fix tips for replacing the cable on an internally routed Fox Transfer dropper post

 

[militantmandy]

Top tip if you're going to be working on your dropper, particularly where the dropper attaches to the cable: shove a tissue down the seat tube around the cable whilst you're working. There may well be a tiny grub screw holding the cable retainer clamped to the cable. You REALLY don't want to drop that down into the frame!
View attachment 87569
Picture credit: Quick fix tips for replacing the cable on an internally routed Fox Transfer dropper post

This is why I will never go back to posts that work this way! Lever clamps for me please.

 

[2WheelsNot4]

Its likely a leaky air cylinder, remove the seatpost and check the pressure at the bottom. If it is leaking then its likely warranty

You could poke the bottom in a basin of water. Bubbles would instantly indicate a leak.