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Suspension & dropper cluster · Fault

The dropper post won't go up

Quick answer

Before thinking about the cartridge —the most expensive part—, check the cheap stuff, which is what fails almost every time: 1) the saddle collar over-tightened (excess torque deforms the tube and slows the bushing: loosen it to its torque, on the order of 5 N·m, and test); 2) the cable too tight or poorly routed (it leaves the lever without travel). Only if the collar and cable are fine do you move on to the cartridge or the pressure, depending on the type. If on top of that it sags when you sit down, that points to something else.

80% of the time it's the one-minute step almost no one does: loosening the collar. Start there.

The order, from simple to expensive

1 · Saddle collar — Loosen it to its torque (usually low, ~5 N·m). If the post goes up with the collar loose, excessive tightening was the problem: it was deforming the outer tube.
2 · Cable and housing — Check the tension and routing. Too tight leaves the lever without travel or the valve half-open. Restore the correct tension and check the housing isn't pinched.
3 · Cartridge / pressure — Only if the above is fine. On posts with an air valve (Reverb type) it may be pressure; on sealed cartridges (OneUp/PNW type) it's usually cartridge replacement, not repair.
Diagnostic tree of a dropper post: won't go up, sags or has play, with their causes
Diagnostic tree: start with the collar and the cable, not the cartridge.
Common mistake: taking apart the cartridge or changing the cable first, without first loosening the collar. Tightening the collar beyond its torque is the #1 cause of a healthy dropper failing to go up.
Still won't go up?

Tell us your post model and what you did and we'll guide you before spending on parts. Message us on WhatsApp

Frequently asked questions

Why won't it go up?

Almost never the cartridge. It's usually the over-tightened collar or the cable too tight or poorly routed.

First step?

Loosen the collar to its torque (~5 N·m) and test. If it goes up, it was the clamping.

And if it still won't?

Check cable tension and routing. Only after that, cartridge or pressure depending on the type of post.

Related

Sags when seated → What dropper fits? → Suspension & dropper cluster →

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BikeLab-pedia · Suspension & dropper cluster / Bicycle compatibility and standards / Carlos Eduardo Ravello Joo · BikeLab Studio · Trujillo, Peru