Why the dropper post wiggle?

Most dropper posts will have a bit of wiggle, that much we know. But after 3 years of some serious enjoyment, the OEM post that came on my Orbea is not just wiggling, it's a full-blown shimmy. It makes a racket going downhill, and the play is obnoxious uphill, but with the rebuild pieces over 2 weeks away from my doorstep, I had to try something.

So I pulled it apart, examined the internals, and tried to see what I could do to minimize the noise pollution and lateral wiggle without the recommended parts on hand. If you are contemplating this, I do not recommend moving forward unless you are familiar with this kind of thing and comfortable with most likely voiding a warranty. This is just what I’m doing to keep myself sane.

The OC2 MC20 is the OEM post from the Basque brand Orbea and can be found on the majority of their bikes, from full suspension to budget hardtails. It has been a surprisingly adequate dropper post for the last few years, hence why I have not swapped for one of the obvious options available. That, and I don’t want to buy something unnecessarily if I can help it.

Pulling the post apart is rather simple, and Orbea actually supplies the instructions in the technical manual through their website with the disclaimer that this process should only be performed by a professional. I’ll call myself a professional in this instance and proceed with my quest for less rattle. Armed with a 3mm and 10mm Allen wrench, I set my sights on the small retention bolt (3mm) that holds the top of the cartridge in place under the saddle clamp cluster, the plastic actuator that (10mm) holds the system together and the two small rubber bumpers between the actuator and cartridge at the bottom end of the post.

I noticed a lot of sloppy behavior at this junction of bumpers, actuator, and cartridge, and after rebuilding the entire post as recommended, things showed no signs of improvement, likely due to the bushing being pretty cooked. This didn't stop the devil on my shoulder from whispering that I could just remove those bumpers I saw near the actuator to tighten things up a bit. Much to my surprise, things tightened up considerably after doing away with these little rubber donuts, and when fully compressed, they gave me a couple more mm of drop. The only noticeable issue I can notice so far is the full extension and compression sound is a bit more positive, which makes sense seeing as I removed what is essentially a bump stop. I will, of course, monitor the condition of the internals regularly to ensure that I am not doing any long-term damage to the component. If the fix ends up breaking the post, then it’s not much of a fix.

With plans to replace this dropper soon due to scratching on the stanchion and a crack in the lower tube, it has served its purpose and will find a place in my parts bin for later use once I find a replacement. This homebrew fix will be an interesting experiment to see if it will solve the issues I have been having before I fully rebuild it with the maintenance parts that are en route from Spain. I’m all for parts being rebuilt and their lives being prolonged, even if it might not be the recommended solution. I have been impressed with the amount of revitalization that is available for this seat post, though. It is uncommon to see such a serviceable OEM product these days, but I hope this continues to change and becomes commonplace.

Overall, I am pleased with the results, and this will remedy the issue, at least temporarily. Over the next few weeks of riding, I will be keeping a close eye on the seatpost's behavior since its .55-gram weight reduction, and very much look forward to replacing the bushings, and lower tube to fully bring this post back to life, keeping it out of the rubbish bin and on the trail for years to come.