The Shock Lab

From a "quick job" to a week-long project 💀

A broken bolt is never a good thing, but when the replacement has been discontinued for years, things get a bit more interesting 👀

This Fox RP23 was pretty awful (slide 2); no oil, heavy corrosion, and the broken piston bolt. So, after checking the options with the customer, and considering the shock size is no longer in production (6x1.25"), we had to bring it back to life 🫡

I started with a 3/8" hex bar of "Extreme strength" 1144 steel, cut it and turned it down to 6.3mm to match the original bolt 🔩

Then, precisely drilled the core for the Propedal needle to seat properly, and single-point cut the 18tpi threads, which may have taken more than one attempt 👀

After giving it some finishing touches and chamfers, it was time to part it off, which was the scariest part of the whole process, of course 😬

Then, I used the lathe as a mill (I know, I know) to make the flat sides and side ports, using an old/damaged shaft to keep the bolt steady for milling and drilling. I had to use very light passes but it worked surprisingly well 🤘

After a bunch of new shims and parts, this RP23 is back to new (or better 👀), ready for another decade with no service 💀 (please don't 😅)

69-axis CNC and fancy tooling would have certainly been nice, but sometimes you have to work with what you have. I have some very "old school" or "basic" equipment at the shop but it has been extremely helpful, even for more complex projects like this, a basic/old school lathe is something I'd definitely recommend for any workshop 🤘

And yes, I know there's a company across the globe that currently makes that bolt, but hey, ordering it isn't as fun as making it 👀

"All that for just 1.25 inches?" I've heard that before, and it's nothing to be ashamed of. We can help regardless of your size! We're still talking about shocks, of course 🫡

Do you have a project that couldn't be fixed or was rejected elsewhere? Holler! I like challenges so the craziest projects may get a better deal 💸

Adjustable Bottom Out bumper? 🤔

The latest Rockshox ZEB and Lyrik (and soon Pike?) feature a non-hydraulic Adjustable Bottom Out (which is why it's been renamed to ABO across all products) 🤘

Teased (likely by mistake) in the webinar/training for the Boxxer release earlier this year, I remember they mentioned the bottom out bumper was adjustable, which I found hard to believe, specially considering the Buttercups are in the way!

But...they made it happen 🔥

So, here's how it works:
The hex adjuster runs through the middle of the buttercup bumpers and rotates the upper gold sleeve (and the air spring shaft with it) to screw it up or down the lower gold sleeve. Both of which are quite mesmerizing 🤤

The bottom out bumper rests against the upper gold sleeve and is pushed up with it when adjusted. It is not pulled back down but it will move back into place the next time you use full travel, of course 🤙

It's worth noting that this does not change your travel. There is still a "traditional" bumper/stopper in the damper side, which is what actually determines where the fork will stop. The adjustable bumper will just engage a bit earlier/later in the stroke and provide more/less resistance to bottom out 🤘

You may have noticed the sealhead looks a bit weird, like it's missing a wiper seal (well, it is), but this groove is actually brilliant, designed to prevent the bumper from ramming oil through the seal head and into the air spring 🔍

The Buttercup bumper is also a bit taller than before, and relatively stiff, so the Buttercup effect 🦋 is very slight but noticeable. Helping "take the edge off" impacts, a similar feel to a 5-10% drop in tire pressure, without the risk of pinch flats, of course 🤌

One small thing; although maybe not totally necessary, and I understand Rockshox usually tries to keep the number of specialty tools low (which I support), but I made a custom bullet tool to eliminate the chance of the quad ring catching on the sharp edge (slide6) 🤘

How does it ride? 🤔
It is amazingly smooth off the top, quite supportive through the midstroke, and allows you to use all the travel efficiently, I'm VERY happy with it after upgrading the damper 🔥

Charger 3.2 + Podium Piston kit 🤌🔥

To put it lightly, the Charger 3.2 was a big disappointment, at least for me. But hey, maybe I was expecting too much 💔

Luckily, I know a guy...

WPS Podium Piston kits for Charger 3.2 will be available in a few weeks!
But wait...what is this, then? 🤔

Meet my new fork 🫡
Featuring a pre-production piston kit adapted in-house using the PPK for Charger 3.1, with help from WPS, of course 🤘

So, what's different, then? Charger 3.1 and 3.2 are nearly identical besides the tuning, however, the midvalve stud is now longer to accommodate their new longer/stiffer check spring(s), which are also highly preloaded. A questionable decision to say the least, but that's just my opinion 🤐

So, after sourcing a more appropriate check spring, making several custom spacers on the lathe and a bunch of testing, pressure balance and suppleness have been greatly improved ⚖️

Additionally, the rebound valving on the Charger 3.2 is INSANELY slow/stiff. I'm genuinely curious, WTF?! 💀 Luckily this is an easy fix.

And of course, the WPS high flow linear base valve piston allows for a smooth low/high speed transition during compression, while the shim stack optimized for the rider (me) provides the high speed support to prevent blowing through the travel, all without harshness 🤌

If you're considering upgrading from Charger 3.1 to 3.2 (or even from Charger 3), DON'T. We've got a much better option for you 😅

That said, the new Lyrik is an absolute weapon 🔥 it just needed a bit of help with the damper.

What are your thoughts on the new Rockshox products? Have you ridden them yet? 🤔

Discontinued Fox Talas seals? Not a problem! 🔍

Remember the Fox Talas? It allowed to change your fork travel during a ride, which could let you optimize the bike geometry for a climb, and then "unleash" it for the descent. Pretty amazing, right? 🤔

Absolutely, but it added a considerable amount of drag and complexity, and it wasn't necessarily reliable. It went through several updates/variants before they completely got rid of the system. 🚮

On top of that, it uses custom seals that were discontinued a long time ago!
For example, the original main piston and outer IFP seal has a 3mm cross section x 22.5mm inner diameter, but it's 3.8mm tall! 💀

Of course, you could stick a 3x22.5mm o-ring in there and it'll probably work, but consider that not only the piston/bore diameters determine the seal squeeze, but the groove width, too! There must be a better way... 🤔

We presented these options to the customer:
1. ($) Install the closest size seal and send it. (Not recommended)
2. ($$$$$$$$) Source or custom make molds to make the custom seals.
3. ($$$$) Buy PTFE sheets of the right thicknesses for custom backup rings and make custom tools on the lathe to cut them to size.
4. ($$) Use Igus Self-lubricating filament to 3D print the custom backup rings as needed.

Easy choice! So I got to work. It took about 10 prototypes (printed in a different material) and a bunch of test fitting to dial the dimensions in ~0.1mm increments, and a couple tests just fine tuning with the tribo filament. The final batch was tempered to further improve their properties 🔥

The result? High precision, low friction Igus backup rings with high wear and temperature resistance that not only brought this fork back to life, but also will make future service straighforward and with common seal sizes! 🤘

Being able to use compounds to machine or 3D print custom solutions is really a game changer, and will allow us to tackle special projects we really couldn't do before. And will open the door for further innovation. Stay tuned!

You can see the Talas system in action in our story, check it out before it's gone!

Custom service, parts and tools. Link in bio 🔗

Riding season is here! ☀️💨🚲

The workshop has been busier than ever, your trust and patience while we get through the "spring rush" are deeply appreciated 🙏🤘

Meanwhile, here's some content from the last few weeks!

1. Another WPS Tuning kit going in a Fox GRIP X2 🔥
2. Quick look at the Fox 36SL internals, featuring GRIP X and partial Glidecore 🤔
3. Quick reminder to service your sh*t 🫡
4. SKF dual compound wipers on Fox 36 🧈
5. Vorsprung Lufkappe for Rockshox Lyrik 🔥
6. Öhlins TTX22m vacuum bleeding with our integrated bladder holder 🔧
7. Angled shaft clamps for Fox 40, these grip much better than I expected, these and more shaft clamp sizes coming soon, starting at $10! 🤘
8. Our FKM/Viton upgrade kits (hottest item right now), perfect to use along OE service kits (full damper seal kits also available) 🤙
9. Stanchion slowly pulling away from the crown (while creaking like hell) 📣
10. Same CSU, taken apart. The Kashima was literally chipping away with the vibration/creaking 💀
11. Charger 3, next to a Charger 3.1/3.2, next to a WPS piston/spring, there's a lot to talk about here 👀
12. DIY lower service kits, making that 50h service as straightforward as possible 🔥

Current estimated turnaround time for service is 8-10 days 🤘
Tools/service kits usually ship the same day 🛫

Professional service, premium seal kits, and affordable tools, all in one place. Link in bio 🔗

Shipping worldwide! 🌏

2027 Rockshox Lyrik...deep dive! 🔍

The latest Lyrik features a beautiful chassis with cutouts on the lowers for weight savings and more uniform cooling after casting, which should improve dimensional accuracy and chassis alignment, this one was a great example of that, it feels like butter, out of the box 🧈

It also features the AirAnnex to increase lower leg volume, this reduces unwanted progression from the lowers 📈

Taking it apart, I found a -small- issue (slides 4-5), likely left after making the grooves on the bushings, this feature may be updated or removed in future revisions, maybe it's not even necessary! (see below) 👇

The stanchions now feature "Butterwagon" dimples and holes (slide 6) to improve oil adhesion and circulation, keeping everything lubricated 🛢️

Lyrik and Zeb now feature an adjustable bottom out bumper (slide 7), to fine tune end stroke support (more on this later 👀), and Buttercups are still featured on both sides for improved compliance 🧈

The air spring is now twin tube (slides 8-9) to further increase lower leg volume, the reduced piston diameter operates at higher pressures (Force = Pressure x Area), and the 14mm shaft increases negative volume to improve small bump sensitivity. All this results in a relatively linear spring rate 💹

They now feature the Charger 3.2 damper, which really is just a 3.1 (almost identical) with firmer tuning...that's right, they kept the dished piston and stiffened up compression and rebound...maybe the Charger 4 is coming soon? 🫠

*Charger 3 & 3.2 side to side (slides 10-16), it would've been fun to have a 3.1 on hand*

Dished pistons and ring shims preload the shim stack, increasing the force required to open the valve, making the low/high speed transition feel harsh, and they often don't provide enough support at higher speeds❗

This really is an amazing fork, but the damper leaves a ton of room for improvement...so...I'm keeping this Lyrik, but I'd be happy to get you one...aand maybe check for metal shavings...and custom tune it, too 🤙

What are your thoughts on the new Rockshox line up? When is the new Pike coming out? 🤔

10 years of the X2, what have we learned? 🤔

The 2026 X2 is not light, but it may be the best one yet! 🔥🤘

Let's take a quick dive into what makes this shock way more reliable and if it was worth the extra weight! ⚖️

The latest X2 is now Monotube (is it even an X2 anymore? 🤔) and features a 12.7mm shaft, this allowed them to increase the lateral stiffness, as the main piston runs directly against the damper body, instead of their flexy inner damper tube 🤘

The damper sealhead now features a wide bushing on each side to further boost lateral stiffness, as well as dual (and thicker) o-rings in the sealhead to prevent premature aeration! 💪

The IFP seal is also much thicker to prevent aeration from the IFP chamber (which wasn't really an issue) and IFP pressure has been increased to reduce the pressure differential between damper and air spring to further improve reliability 🤘

That's all great news, but what's the downside?
Increasing the thickness (and number) of seals increases friction, and it's definitely noticeable! But a slightly "draggier" shock is better than a heavily aerated one, don't you think!? 😅

One thing I can already tell will be an issue is the air can (again!), the wiper seal is very soft (same as Float X) and does not do a great job actually wiping sh*t off (literally), this leads to contamination ingestion, which leads to seal failure and air leaks!

And guess what...you still can't service the air can without having to take apart the whole damn shock. WHAT IN THE ACTUAL F*** 🤬

The damper seems to be their most reliable yet, but that's worthless if the air can starts leaking. You still need to disassemble the whole thing! 🙃

But hey, at least they're finally using a thicker air can quad ring! (Same as Float X) 👀

Can we improve it? Absolutely!
Our FKM seal kits for '26 X2 feature a FKM X-ring for the IFP, 1x stiff sealhead o-ring (damper side) for superior durability, and 1x softer o-ring (air spring side) for improved sealing effectiveness against the smaller air molecules! This results in reduced friction without compromise in reliability 🤘

What are your thoughts on the new design? 🤔

Banana for scale by Printlabs3D! 🍌