So I’ve got a 150mm internally routed brand X Ascend dropper. Had it about six months now and it’s been fine up until last week. Basically pushing the lever wasn’t making the post actuate. In fact the lever was really stiff and barely moved. Now for the odd part.

The bike is usually kept in the shed. On the cycle into work the dropper was fine. But at the end of the day, of it being kept in the office it didn’t work. However cycling home it started working. I’ve done a bit of testing and it seems like the issue only occurs when the bike is warm/kept inside. Stick it outside for half an hour and it’s fine.

I was thinking the cable may be sticking but it’s odd that it’s only happening when it’s warm. Before I take it apart I wondered if anyone else had come across a similar issue?

I’m calling sticky cable. Mine went in 6 months also.
I’ve replaced with sealed cable system as it was a pain to get it in / right. I don’t fancy doing it often.

Mine gets shitted up now and again. You’ll need to remove it and clean the release mech. Fit a new cable and she’ll be good as new.

A friend had a similar issue and there was a kink in the hose/cable but as it was internally routed we couldn’t see it until we removed it. Straightened and new inner cable and it’s been fine since.

Thanks all. I’ll stick a new inner on some time this week.

I had the exact same thing happen – went from a warm room to cold outside and lever just locked up. It was only the second ride on a new post though, so I loosened off the tension on the cable adjuster and it came right. Has been fine since (two rides). My guess is that it’s a quirk related to temperature and sorts itself out when everything equalizes to the same temperature.

This problem seen to appear when the bike have been cold and gets warmed up.
The oil in the chamber expand and make it hard to actuate the post.
Try to Keep the post lowered a little bit until it gets to room temperature and then release it.

Could it be as simple as having the seatpost clamp too tight?

Maybe when it warms up in the office it all expands enough to squeeze the post that little bit too much?

I remember reading in the manual when I installed mine that excessive clamping force can squeeze the tube and prevent the internals from working properly.

Don’t think it’s the seat clamp as it’s the actual actuator that’s not working. Also I undid the seat clamp and tried it just holding the post in plate by hand, no joy.