Not sure I'm reading your description correctly but are you saying
i) when the post is not at full extension ... and you lift from the saddle ... then it tops out ?? then drops back.
- After you do this then it compresses ??? only at the top of its travel ... but no where else ??
or
ii) at full extension ... when you sit on the post it compresses approx 20mm
or
iii) by last 20mm of travel or so (ie at the bottom of its travel) it is spongey ??
i) => lifting from the saddle
You should train yourself not to lift the bike from the saddle. There is no mechanical stop built into the KS design to stop it from topping out. You can only lift from the saddle when the post is at full extension ... as this is the only position where the post can no longer extend.
- pulling up from the saddle sometimes aerates the damping fluid in the cart ... so it becomes spongey until it dissipates and returns to normal.
The key here is that the post behaves how it should elsewhere in its travel. EASY FIX
ii) =>if the cart is "bobbing"or compressing anywhere in its travel persistently then the cart has failed and needs to be replaced.
no post is bullet proof unfortunately, there is a failure rate, no matter how small. Send it to Pushie and we normally turn it around within the week, depending when we get it. EASY REPAIR
iii) => If the issue is just at the bottom of its travel ... what is happening is you have air stuck in the mast (between the mast and the Cart ... which is acting like negative spring rate and pushing up on the cart as you try to lower it. Usually this happens because the post is full of mud and needs a service, or you've just serviced it and the lube needs to thin. EASY FIX
this vid shows you how to open up your post so you can clean the puppy.
https://www.youtube.com/watch?v=SOYjhtPFZ4I
Basic service is $35 + return shipping if you don't have time to DIY
email
sales@pushie.com.au if you'd like our "how to guide" on performing a relube with Slickoleum ... preventative maintenance is the key to keeping all brands of posts nice and smooth for longer.
If in doubt contact Pushie and we can walk through it.