Pike Open Bath Cartridge Kit
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Rockshox Pike Charger Cartridge Upgrade Piston/Valve Kit

Technology

 

Discontinued

 


 

 

For those who want to keep the Charger damper and want a lower cost alternative to the complete cartridge replacement

Keep in mind this kit does not reduce the maintenance issues associated with the sealed charger damper.
We highly recommend you upgrade your pike using our open bath damper.

We are offering a replacement compression valve and rebound piston kit for the pike.

This kit will allow you to revalve and add adjustable midvalve to the charger damper. It will also have a more independent way to adjust the high speed without affecting the mid and low speed damping. The stock rebound valve does have a midvalve of sorts, it is a 16 mm x .15 shim supported by a check spring with a bit of resistance.

Rockshox is using the same size cartridge as ours, (they use the same 20 mm cartridge and 6 mm ID shims that we use) and our rebound piston and compression valve from our cartridge fits right in and allows us to offer this as a tuning option for the stock internals. This would give riders the option to retain the charger damper system and add features to the internals that create tunable midvalves, compression and rebound ported valving and reshimming options. The stock piston and valves are very limited as to what you can do to the shims for revalving and midvalve.
We hope to make this a self install kit, with shims to tune with, and a complete tuning guide with instructions.

The Pedal/Lock-Out knob can be converted to three different compression adjustment set-ups:

Standard - The high speed adjustment acts like a low, medium and high range damper control
Advantage: You can easily add more high speed compression and shift the low speed range up about 5 clicks
by just by flipping the knob up one or up two.

Independent - The high speed adjuster is independent of the low speed
Advantage: The low speed can be dialed independently of the high speed for more fine tuning downhill settings.

Pedal - The high speed adjuster retains more of the pedal/lock-out feel
Advantage: Adds more low speed and and creates more of a platform feel for long climbs
without the mid to high speed harshness of the stock pedal/lock-out feature.

The Piston/Valve Kit for the Charger Damper

Compression valve and rebound piston

* New Compression valve with converted independent high speed adjustment(RCT3 only), soft med, hard(open, pedal, lock),
retains 12 clicks of low speed adjustment in all high speed positions.
* New Rebound valve with adjustable midvalves and 2 stage tapered rebound valving shims



The optional revalve kit will come with an assortment of shims for revalving, and 3 high speed springs for tuning.
We will supply a set-up chart with options for tuning, based on air pressure, type of riding, and skill level.

1 - 4 port compression piston with o-ring
1 - 4 port rebound piston with piston band
compression shims
rebound shims
midvalve check plate, spool and spring assembly
midvalve shims
Optional soft and hard high speed spring for adjustment range changes
sleeve O-ring
charger o-ring rebuild kit
Optional 5/8 hex tool for servicing bladder available


Need us to remove the cartridge from the fork, just send your fork to us and we will install it for $100 including Spectro 85/150 oil. See below to add to cart.

Charger Cartridge Upgrade Piston/Valve Kit

 

 

Compression Piston
and
High Speed Adjustment Range
Spring System Included

 

 

 

 

 

 

 

Rebound Piston and Midvalve Assembly

 

 

 

Discontinued

Rockshox Pike Charger Cartridge Upgrade Piston/Valve Kit, $229

Custom valved and set-up to rider weight, ability and riding style

 

Choose the type of riding that you will be doing so we can custom valve it to your specific needs.

Click here for a description of our definitions

Type of Riding

Choose your fork model that the charger kit will be installed in.

Fork Model

Choose rider weight.
Rider weight is without gear, we add 5-7 lbs for DH gear, 7-10 lbs for All-Mtn/Freeride.

Rider Weight

Choose the spring rate/air pressure you will be using which gives you 22% sag.
We need this number to help set-up your fork rebound damping correctly.

Click here for sag setting Tips

Air
Pressure

Choose your rider ability for us to set-up the charger kit.

Rider Ability

Choose type of high speed adjuster mod, RCT3 only.

High Speed Adjuster Set-up

 

 

 

 

Have us remove, modify and reinstall your cartridge for you

Ship us your fork, we will modify your Charger damper cartridge
includes Spectro 85/150 Oil

Add option here, does not include shipping back to you, we will adjust your shipping total depending on where you live in the world and send you a Paypal invoice for the difference. This is not a rebuild, it assumes your fork is in good working condition with no leaks or scratches on the stanchions.

Price $100

 

Installation

Price $100, plus shipping difference

 

 

 

 

 

Compression/rebound stock internals for the Charger damper

 

 

Stock Charger Rebound Piston and check plate assembly.

 

Stock Charger Compression Piston with Pedal Lock-out plate, notice the very large 2 port design with the threshold rim loaded valve.
Makes for a good on off switch for pedal and lockout but does not allow for fine tuning of mid and high speed adjustment and valving.

 

FAQ'S

The damper seems to have too much slow/low speed compression and feels a bit spikey on slow bumps?
There seems to be too much preload on the check valve plate on the rebound piston. We managed to make a sleeve to space out the check plate but there is not enough room with the wider stock piston. Still has too much preload and this is causing the low speed harshness, sort of like a midvalve with no float. We ended up installing our whole midvalve assembly with our piston.

Just seems extreme ditching the Pike bladder for open bath, in that case might as well set up a Lyrik.
We agree, we feel the charger damper is a good but it still has a few areas that could be improved or changed. Firstly it has a pedal/lock-out knob that is useful for some but most seem to want more tuneability for the downhill or open mode. Secondly it needs a way to tune the shim stacks rather than the threshold adjust system it has. By converting the pedal/lock-out knob, changing the piston and threshold system to a independent high speed adjuster it now can be adjusted in all positions for increased adjustment range for descend riding. Essentially 3 clicks of high speed with 12 clicks of low speed for each high speed setting. Thirdly the rebound piston needs to be able to accommodate midvalves that can be tuned, the charger piston and arbor needs more space and features to be able to do this so since our 20 mm rebound piston fits right in (yes, Rockshox used the same cartridge 20 mm tube size and 6 mm shim arbor as we do, how convenient!) This is why we are offering a replacement piston/valve revalving kit the improves the performance, adds midvalves and converts the pedal/lock-out knob to a high speed adjuster. For those who want the smoother, reliable and maintenance free open-bath cartridge we offer that too. The same pistons and midvalves that we use in the open bath system.

Will this add high speed adjustment to the RC?
The RC does will not have the high speed adjust as it does not have the lock/pedal knob, this knob is what we are converting when we make the high speed adjustable, all other features will be added including the ability to preset the high speed spring rate.

How is the HSC range with just the 3 settings?
The HSC has a wide range with the standard HSC adjuster spring, we also provide a softer and firmer optional spring that could be installed for finer tuning or even wider range. We convert their threshold adjuster into the HSC adjuster, we are using this mechanism to change how it controls the stiffness of the high speed shims, so when converted it uses the same 3 positions as before, we would call them soft, med and hard settings rather than the open, pedal and lock. Soft has no preload from the HSC spring, medium uses about 4 mm of preload and hard uses about 8 mm. The goal is to provide more useful range of adjustment rather than settling for one or two clicks that sort of work.

I'd bet most riders on a Pike spend almost all their time in the Open mode. To bad to have 2/3 of a shock's settings barely being used.
Yes, we feel the lock is completely worthless for this kind of fork and the trail or pedal mode is still way too stiff for most, so why not convert it to a more usable setting, this is what our kit addresses. The trail setting or pedal mode with the low speed set at 6 out becomes the standard setting or midpoint between harder and softer overall compression. Click it to lock-out and it is firmer high speed compression with the same low speed or click it to open and it it will be softer high speed compression. This high speed compression range is controlled by one of the 3 high speed springs and the shim stack arrangement options we provide with the kit. When lighter low speed settings are selected the dive will be addressed with the midvalve system added as part of the kit, this comes with adjustable shimming options too.

Are we going to change the low speed needle adjuster flow?
We are leaving the adjuster needles stock, they have a bit more range than we want, but still do a very good job fine tuning, doing this will add too much cost(compression side) and install complexity(rebound side) to the kit.

I'm not OK with 2/3rds of the fork's setting being unusable because the Trail is too harsh, the Lockout is useless on a trailbike.
Yes, other the past year we have been following the complaints about the Pike charger damper and have developed a bunch of design changes to address them, overall a much better damper than the mission control, but it should be since they used our cartridge dampers as guidelines to make a mass production version with their own twist on it. We are just converting it to a more useful adjuster system, adding our finishing touches and custom tuning it for you.

I assume the nitrogen sleeve is a phase 2 for your mod - yes? I see the ultimate value of the mod over the Open Bath
to be weight, resale appeal (no drilled holes, chassis mods)
Yes, this is an added option, again not required for all, as most riders will never push it hard enough to notice, ie it would be for firmer midvalve options and higher speed compression hits. The sleeve actually is very light, 25 grams essentially a thin tube 105 mm long. The open bath btw does not need and drilling or mods, in fact it would be a very simple self-install. The charger upgrade is a very technical tedious disassembly and reassembly process, the oil needs to be bleed exactly correct and maintenance is very sensitive to the performance. Any shock pump with a needle connection will work it does not need to be nitrogen, it will only need a few pumps to get to 20 psi. If the new owner wanted it would still function wit or without a charge. All properly valved sealed damper systems will always out perform an open bath in the most demanding damping conditions, it just may not be needed for most riders and you get all the complexity and maintenance issues. You also get the high speed adjustment feature, this is a big portion or the weight difference between the dampers.

if you want your shop to do it instead of you (maintain like a stock Pike per se). Wouldn't the nitrogen sleeve take away another chunk of the 110g weight savings and limit the ease of maintenance since you need a new nitrogen charge after servicing - leaving just resale appeal? Do you believe the nitrogen sleeve version would outperform the Open Bath in any way? Just seems like sucking up the 110g and going open bath may be the easier path :) Thoughts?

All dampers can cavitate when the pressure behind the piston drops below the vapor pressure of the fluid, this is why shocks are charged with nitrogen to keep the pressure applied to the fluid preventing this from happening. Most forks are filled with oil and have a smaller air volume that gets compressed as the fork compresses, this naturally works well in open bath preventing cavitation. For some reason MTB suspension companies are not aware of this issue and have been designing sealed dampers with no exterior way to increase pressure on the oil, i.e. they don’t put enough outside oil to cause this ramp up. MX suspension companies realize potential cavitation issue exists and design If the free bleed is big enough the pressure does not drop behind the piston. This is all good, but if you don’t create enough damping to hold the fork up on low speed conditions then what is the point. The issue is the addition of midvalves to prevent fork dive, can easily create low pressure behind the piston, especially if the main compression valve is soft or has a lot of free bleed, this is where the nitrogen charged bladder will prevent the pressure from dropping, it does not add any damping force it just adds to the air spring rate so you might run 2-3 psi less than the stock damper.

Would your mod not give me a better damped system and the midstroke support smooth out the rebound system ramp up?
Yes this is what we are trying to do, but it does create lower pressure behind the rebound piston.

So I get less change in forces on the Charger bladder?
Yes, I guess this could be an issue if the compression valve is set to soft and it might try to drive all the oil into the bladder after separation occurs in the oil from cavitation.

I understand that the friction connection and it being a bladder means if the force is too large the bladder can burst or break the connection?
No the bladder is kind of restrained by the fork tube, it expands to about 30 mm when filled properly, the id of the tube is 31.4 mm. The Nitrogen sleeve will be 29.5 mm ID and will also restrain the bladder similar to the shock's piggyback reservoir.

But I keep seeing the lockout and existing rebound system system introducing larger deltas/spikeness which should be worst case - no?
The lockout is upstream of the valves and pistons and does not create cavitation or any extra pressure on the bladder, it is all taken out at the compression valve.


Keep thinking I want to do the mod (sounds like exactly what I want to change) and not just go open bath, but concerned with the longevity of the RS bladder design itself - is it still a weak point that will ultimately fail over time.
Adding the nitrogen sleeve will actually help prevent the bladder from breaking or ripping out of the end clamping sleeves. The bladder generally only fails if over filled and stretches too much causing it to tear at the clamping sleeve. It is not an issue with the failure of the bladder but letting it bulge without resistance therefore not adding any pressure to the oil. The bladder is just a simple piece or rubber tubing made of neoprene rubber, very cheap and easy to replace.

 

techinfo@avalanchedownhillracing.com