The RockShox Reverb is a hugely popular dropper post and it comes as standard equipment on a huge number of bikes nowadays. It's available in a number of different diameters and also a number of travel options, ranging from 100mm to a whopping 170mm.

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Therein lies the problem. If you have an older post and want more travel from it or you've bought a bike that comes fitted with a long dropper post but that means you can't get the saddle low enough at full extension - you've sized up the frame you've bought for example - is there anything you can do?

We asked SRAM and the short answer is this:

"No."

It turns out that each Reverb post is designed specifically around a travel. It's not as simple as it might be with a set of forks where, for example, changing the length of the air shaft allows you to adjust overall travel, letting one fork chassis cover a wide range of travel options. Each Reverb travel option has a specific set of internals and measurements for the outer and inner post plus the shaft inside all of that.

That makes sense for a short travel post - there's not enough material there to allow it to be run any longer - not enough overlap between the inner and outer posts would lead to failure and a horrible human shishkebab, even if you changed the guts.

For a longer post, it's a bit more complicated, but the essential answer is still no. We found a Reverb lying around and whizzed it apart to see for ourselves. While you could theoretically use some kind of bottom out spacers to reduce the overall drop of the post, that wouldn't change the fully extended length at all, which is the main issue you'd be trying to get around.

To do that, you'd need to reduce the length of the actuator shaft inside the post. There are two options here, one of which is to cannibalise a shorter travel post for the requisite parts and use those. Obviously, if you have a Reverb of the right travel lying around then you'd just be better using that in the first place, so this option is fairly pointless. Even if you had a broken post, you'd have no guarantee that you wouldn't be switching a broken part into the previous working post.

The second would be to modify the existing part, which isn't anywhere near as simple as it might seem. You'd need handy engineering skills and machine tools, so it's not practical for most people and not really advisable for anyone.

So, we're sorry to be the bearers of bad news, but if your Reverb is the wrong length for you and your application, your best option is trying to find someone to swap it with - or selling it and buying the right one.

If you're really desperate, then trying to lose some height from your frame's seat tube itself might be an option, but we shouldn't really have to tell you how much of a high-risk option that is and that no one in their right mind would recommend it.

So don't.

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