I have a KS Lev on a bike that’s been sat untouched for 6 months or so. I decided to have a play the other day and it appeared the KS Lev dropper had dropped about 5cm over time. It was perfect before being sat around and had been serviced by South Coast a few months prior.

I pulled it up and it extended but was dropping back down when any pressure was applied to the saddle. I figured it might have lost a bit of pressure so I pumped it to 240psi (250 limit) but this made no difference so I let out all the pressure and then took off the bottom cap to see if anything obvious was awry.

I then pumped it back up again and now its got negative pressure and is sucking down about the same amount. I can pull it up manually and it pulls back down. It locks in the low position so is actually usable but missing a third of its drop.

Any thoughts?

Sounds a bit like when RS forks would have their positive to negative chamber transfer port blocked causing the fork to pack down.

Not sure if the LEV has a positive and negative chamber and if it’s possible to reset the air pressure without a full rebuild?

Thats exactly what it feels like. With my pikes I had to let some trapped air past the seals with a zip tie but I can’t see any way to do that with the post.

dont think they have a n-ve chamber or anything. Id suggest the cap is too tight on the bottom?

The lev can suffer from sag issues if the cable is ever so slightly too tight/wound on. That may combine with a tight seatclamp to give you some strange effects. It probably isn’t, but they are easy things to check first!