The Shock Lab

Coil shocks don't need to be serviced. Or...do they? 🤔

Fox DHX2 standard 100h service 🔧

"That's why I ride a coil shock"
- Dozens of people in the comments when we post an aerated air shock 💬

A coil spring only replaces the air can, that's it. The complicated bits are still inside the shock. In this case, the DHX2 is nearly identical to the X2, just without the air can, it can still get aerated 🫧

"But you said the X2 gets aerated from the air can"
And I'm glad you're paying attention. It's quite similar, actually 🔍

The DHX2 (and other 🦊) use a u-cup seal for the sealhead, instead of an o-ring or x-ring. These are "single-sided" seals that are meant to stop the oil from leaking out. But they do absolutely nothing to stop air going into the system 🙅

"But why is this important, isn't the shock pressurized from the inside?"
Yes, when static the whole damper is pressurized to 125psi. BUT...

During fast compressions, the piston moves so fast, that the pressure behind it can drop. In fact, it can drop below atmospheric pressure 📉

And...can you guess what happens when the pressure drops below atmospheric, and you have a single sided sealhead seal? 🤔

That's right, air is actually sucked into the shock over time, resulting in that noise we all love, which also turns your dials ineffective 👎

But...that's not all 😬
The u-cup seal has a very narrow contact surface with the shaft, which reduces friction. But it's also very prone to leaking with minimal contaminants. Oh, and they're made of a very soft compound 🫠

And of course, the wiper seal is pretty weak, softer than what you see on other brands, allowing for dirt ingestion, which damages the u-cup seal, resulting in oil pouring out of the shock 💦

What does this all mean? It just means the DHX2 is a high maintenance shock. Just like its air counterpart 👯‍♀️

Can we use better seals instead? Yes. But we're still testing on all DHX2 variants ⏳

Higher IFP pressure and proper tuning can also prevent these pressure drops, making the shock more reliable 💪

Now, are there simpler and more robust/reliable coil shocks out there? Yeah...

🎥: Max Guerra
🔧: mos

Dual Axle Steering. Co-developed with Mercedes 🔥

No, seriously, why would you want your shock to wiggle? 🤔

These are spherical bearings, they allow the shock to pivot like a standard bushing, but they also allow for side-to-side rocking to self-align the shock to the frame 📏

Your frame flexes under load, some more than others, and this flex can result in the frame effectively trying to bend your shock. Needless to say, this is REALLY bad for any shock 👎

Spherical bearings keep the shock aligned with the frame as it flexes, reducing side loading and preventing premature wear or even broken shafts/eyelets/bodies 🔍

These are widely used on MX and automotive shocks (and many more applications), but aren't as common on MTB, mainly due to sizing constraints, as they usually require a bigger eyelet bore ⭕

That said, many of the most common issues we see on modern bikes could be prevented or eliminated by spherical bearings 🎱

But, instead of that, the bike industry decided to give us Trunnion mounts and clevis extensions, which give the engineers some extra flexibility on design, but for the shock it's the exact opposite. Often resulting in premature wear and/or failures 🙅

Unfortunately, this isn't a "bolt on" upgrade in most cases, the shock needs an eyelet designed for it 🥲

Brands that use (or have used) spherical bearings include: Öhlins, Vorsprung, Push, DT Swiss, 5th Element, and Manitou (I think) 🤔

What do you think, would you like to see more brands offer option for spherical bearings? 👇

"Oh, you thought that was complicated" 💀

Meet the Fox BBC 🦊🍆💦 - Variable Valve Control

Found on GRIP2 and GRIP X2 dampers, the VVC is a brilliant way to externally adjust shim stack stiffness without adding digression. But it comes with some drawbacks...

The variable valve control uses a set of symmetric spirals which contact a wing shim at different points of its length to adjust the effective stiffness of the stack 🔍

When the adjuster is fully open, the wing shim contacts the spiral at the widest point, this makes it easy to bend the shim due to the increased leverage 📈

When fully closed, the wing shim contacts the spiral much closer to the center, making that same shim feel much stiffer 💪

Think of pushing a door, when you push by the handle it's easy, but try opening a heavy door with your hand right by the hinges. It'll become much harder! 🚪

As someone who's obsessed with new tech and cool sh*t. I love this, but at the same time: How much do we really need externally adjustable HSR? 🤔

It is by far the trickiest adjustment to get right, as most people really struggle to even identify what it's doing. BUT, get it wrong, and the fork may either become unstable or start packing up with consecutive hits 🙅

In addition to this, the high precision required, along with poor consistency in assembly at the factory often leads to the adjustment being out of range or plain ineffective, which could mean the "manufacturer's recommendation" ends up way off 👎

Keep in mind, every decent fork has an HSR circuit, but it's usually a shim stack that can be custom-tuned to the rider, internally 🔧

But, what do you think? Is the external adjustability worth the extra complexity? 👇

This trick could be considered cheating 🔥

Vorsprung Suspension Smashpot installation 🧈

Considering the video is pretty self-explanatory, today we're talking about fork upgrades, in general! 🔍

There's a bunch of upgrade options out there, and this can make things a bit confusing for some, so let's try to separate them into different categories and explain their benefits 🤘

1.- Friction reducing upgrades:
These can go from cheap to "have a seat", from better lubricants, lower friction seals, to a full coil swap as shown. These are usually something you feel right away, as dropping friction is most noticeable at the beginning of the stroke 🧈
Examples: SKF dual compound wipers, WPS FL01 oil, Vorsprung Smashpot...etc.

2.- Spring curve upgrades
These are focused on improving the spring curve, either compliance, midstroke support, bottom out protection, or all of them. These may not have a direct effect on friction, but some of them may feel like it due to a softer initial spring rate 📈
Examples: Vorsprung Luftkappe, Secus & Smashpot, Diaz Runt, MRP ramp control...etc.

3. Damper upgrades
These are focused on controlling how the fork handles at speed, shaft speeds I mean. The main job of the damper is to slow down impacts as they happen and control return speed. A properly tuned damper provides great big hit support while remaining supple, and recovers quickly for the next hit without feeling nervous. These upgrades are usually the hardest to notice, specially for beginners. But they're often a great idea for experienced/aggressive riders, as well as anyone considerably lighter/heavier than the "average" rider, specially if you're at the end of your adjusters range 🎛️
Examples: Custom tuning, WPS piston kits, complete damper replacement...etc.

In my opinion, most riders should consider them in the order shown above, reducing friction is the biggest thing you'll notice, and some of these upgrades are dirt cheap. Keep in mind the service itself will drop the friction considerably just due to fresh seals and lubricants! 💦

These upgrades (and more) are available on our website. Link in bio 🔗

What upgrades did we miss?
What should we dee

*New failure unlocked* 🔓

It's common to see aeration on these but... things really went sideways this time 👀

If you've worked on these DPX2s (and old Float X), you may have noticed the IFP wiggles around considerably in the reservoir, you can clearly see this when filling the shock under pressure 💨

This can result in the reservoir surface wearing out over time, but this one was in a rush to get a new reservoir 😅

The IFP needs some clearance in order to slide up and down the reservoir without rubbing, but excessive clearance results in the piston tipping over and rubbing anyway 🙅

So, how can you prevent this? 🔍
Well, one option is to make the IFP from a low friction material, like the Brass pistons found in Monarch Plus shocks, these are (slightly) less likely to damage the sealing surface 🙂

Newer Rockshox shocks use a plastic IFP with a special, longer profile with a slight relief which is filled with oil, this helps keep the piston aligned, even without the piston itself making contact 🤘

And finally, the newer Fox shocks use a glide ring on the IFP, this works beautifully to keep the piston aligned 🤌

Interestingly, the IFP from the new Float X fits on DPX2 (and old Float X), which completely prevents these issues and it's a great update for these 🤙

Have you seen these go sideways before? What do you think was the cause? (Besides poor design, of course) 🤔

Excuse me...how much?!?! 🫪

Another generation of Transfer, another $1500+ in tools 🫠

One of the craziest tools I've seen, the upper bushing removal tool for Fox Transfer, I mean...it really isn't that expensive for what it is, but it's definitely crazy for what it's for 💸

Its job is to literally force the upper bushing out. The long, threaded tool is inserted into the lower post and must be used reinstalling the circlip to then thread it in all the way until the bushing comes out...two hours later 🤣

Oh, and don't forget you need the extension for 175mm droppers (398-00-594), sold separately, of course 🙃

But seriously, a couple taps with an appropriately sized rod and it's done...not sure if they didn't think of it, or if they chose not to 🔍

This can even be done more durable and professional by using an aluminum or steel rod with slider bushings that could be replaced separately...ok I'll be right back 👀

The rest of the tools (and the dropper itself) also leave a lot to be desired, but looking at the bright side, the 2025+ Fox Transfer is easier to service and doesn't require an arm and a leg worth of tools to service 🔧

Anyway...what other tools should we look into? Maybe they can also be replaced by a piece of plastic 😏

Check out our story, we've got more crazy tools posted! (Always) 👀

Other tools dropping soon:
15mm hex tool for thru shaft
More delrin rod sizes!
IFP pullers for Fox and Rockshox
Laser-cut wrenches and more
2021-25 X2 VVC tool (somehow)

What else should we add to the list? 🤔

"We're happily losing money with these..."

Fox Transfer! We used to NOT work on these at all, and there is a few reasons... 👀

First, the manufacturer used to charge just $99 to rebuild these...including parts! Which is beyond a good deal. I remember hearing "we're happily losing money with these..." several times during training/clinics years ago, which honestly dropped my interest immediately 😅

But then, I looked at the tools...and it all started making sense
Whatever they were "happily losing" on the service was coming right back in tools alone, they didn't care to screw us all over with the prices 💸

"Hey, calm down, that's a bit crazy to say..."
Yeah? You think $60 is fair for a f*cking plastic rod?
What about the $92 plastic IFP tools? The ones they dropped to $25 for the newer model. WHY THE F*CK WERE THEY $92 IN THE FIRST PLACE?!?!
And the $400+ bushing removal and installation tools? THAT'S $400+ EACH.
WE'RE LOOKING AT OVER $1500 OF SPECIALTY TOOLS TO WORK ON EACH GEN OF THEIR DROPPER. WHAT THE F**** 🤬

Anyway...(I almost lost my cool there)
They only get away with it because we keep buying their sh*t. And that includes service kits, tools, replacement parts and more. And not just 🦊

When you can, try sourcing tools and supplies from small businesses. And no, I don't mean buy from me, there's many people out there with an actual incentive to make a good product. You can even source/make the parts/tools yourself! 🤌

When we all stop buying overpriced sh*t, you'll see the prices magically drop, why the f*ck are we paying $90+ for a dropper service kit? (Rockshox), $60+ for fork wipers (Öhlins), $60 for a damn plastic stick (Fox)...the list goes on...we need to stop that sh*t, don't you think? 🤔

What's your best example of a crazy overpriced part/tool? Post the part number or a picture! 👇

Is this the easiest tool to DIY? 🤔

This is the Handy tool, possibly our simplest, yet most widely used tool 🔥 And I'm showing you the process so you can make your own 🤘

Available on 303 Stainless and 6061 Aluminum, the Stainless Steel Handy tool is one of our best sellers, and one of my personal favorites as well 🤌

From a punch/handle for removing hardware and bushings, to a quick and sturdy lever to loosen up eyelets, it's even a great self-defense weapon (assuming you're Bruce Lee or something) 🥋

On a side note, a lathe (and 3D printer) can be one of the best investments you can make for your workshop. You can literally turn raw material into tools and parts, it really is a tool to make more tools 🔧

A few months ago, I had no idea what feeds and speeds even meant...
Today? I still don't, but I'm having a blast 🥸

Now, go make your own!
Otherwise you can find them available on our website. Link in bio 🔗

The next project may not be that simple 👀