Suspension Gurus - Can you help a Clyde Decoy rider?

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
I've read/re-read the tuning sticky...watch all the videos, but need some help for a heavy rider.

I borrowed my (generous) friend's Shockwiz and went down a tuning rabbit hole for the past 2 weeks and have uncovered that I'm likely too heavy for this bike frame to be running an air shock. I'm on Decoy29 Pro w/ Fox DPX2 rear shock.

I'm 270 lbs with hydration/gear, and used ~ kitted weight PSI for several months before I had access to the Wiz. Had initial pedal strikes, learned how to ride a bit better, but also put flip-chip in 'high' and bought some volume spacers. Ended up using the light-blue and thought I had things "dialed".

Along comes Shockwiz. The 36E fork was pretty easily nailed and just ended up with wide-open HSC/LSC and reduced some PSI from Fox's manual recommendations. The DPX2...not so much. After proper calibration and 100% confidence in suggestions, the Wiz recommends: Add air, reduce vol. spacers, soften LSC and HSC. Dynamic sag was near 50%. Next ride was @ 300psi/smaller spacer...same recommendations. Then 314psi/smaller spacer...same recommendations. Yesterday 330psi (!) and the smallest 0.20in^3 Purple spacer - FINALLY - Wiz stopped saying "Add air / remove spacer". But LSC and HSC are still too hard. These are the same suggestions by the way in Neutral+Poppy and Neutral+Planted, which is where I want to be.

At 330psi, there is little suppleness left. It's totally ridable and still a fun bike but the ride is very busy with lots of chatter. I'm also now sitting up pretty tall (still at ~ 38% dynamic sag though according to the Wiz), and feel like I need to flip my chip back to "low". Fox says "Shockwiz data aren't accurate for Fox products". I don't really buy that. The Wiz still collects repeatable objective data, whether or not the data are accurate, they are repeatable and it's better than the human butt-dyno. But when pushed, Fox says a custom re-valve would be required to get LSC/HSC any softer. I'm simply at the limits of adjustment on both rebound and compression. At least rebound is nailed within 2-3 clicks from closed.

I called a few revalve services places and the YT code Float DPX2 CEC001 is a bit of a mystery. Some shops warn any revalving may not change or improve the ride at all. It's a crapshoot. The NEW Float X might help a little if the predicted 40psi reduction is true, but 290psi is still a very hard air spring.

Avalanche Racing flat-out refuses to do an air shock for a Decoy client. The owner Craig says the Decoy frame leverage ratio is already so progressive that an air spring is simply the wrong type of spring to use...period. For any rider weight, in his opinion. Decoy sag requires a LOT of spring force to settle at 33% and in my case that happens to be 330psi. He predicts at that PSI, my shock is a ticking time bomb and that adding volume spacers are going the opposite direction of what's needed.

His recommendation is 650# or 700#/in coil on Bomber CR or Fox Van RC, custom revalved by his shop. Details of what they do are listed here: Fox Van Rc and Bomber CR Speed sensitive Damper SSD mods.

The cost is something like $730 for the shock, spring and custom valving . This seems very reasonable given the price of say Push 11.6 options and just a hair more than say Fox DHX2 with standard spring.

He does warn that doing a coil out back and standard Fox 36E air spring up front may be wonky and out of synch...he recommends coil on both ends.

Before pulling the trigger and waiting 3 months - I wanted to see what you other heavier riders are doing out there faced with this situation. He mentioned one other guy that's 300# on a Decoy, so I'm not the only one out there I'm sure.
  • Has anyone had experience with a re-valved DPX2 off a Decoy? Did it help?
  • Is air really the wrong spring for the Decoy?
  • Is 330 PSI really that dangerously high? (even if I'm willing to tolerate the lack of suppleness) - Craig says "it's a time bomb" while Fox says max psi is 350. I want to avoid a blown shock given COVID inventory backlogs.
  • Would the new Float X (also 350 psi max) be a better option for heavier rider, or will it be the same story since it's air-sprung?
  • Have any of you coil-converted riders looked back and missed the liveliness of your air shock?
Am I missing something or is coil the smarter way to go with this bike and my weight?

Thanks in advance all!

IMG_3971.jpg . IMG_3970.jpg
 
Last edited:

Sapientiea

Active member
Jul 12, 2019
296
192
Netherlands
Hi, I weigh 229 lbs (without gear) and I have the Rockshox Deluxe @ 250-260 PSI (with gear), rebound 5-6 clicks from full fast depending on terrain and no volume spacers. Ride at 30% sag, dynamic I do not know. It functions well and happy with the performance. I used most of the shocks range during an alpine ride. Bigger drops (>0.5m) to flat and I am getting full travel. Mind you I am NOT a super aggressive rider, no large jumps, no DH races and so on. I usually do technical ups and down (slow). Not sure if it helps :)
 

Poupy

Member
Mar 27, 2020
35
10
France
Hello,
I am at 220 lbs with equipment, with the fox dpx2 I need 300lbs for 35 of sag.
fox dampers need more pressure than rockshox. currently I have a dhx2 with a 500lbs spring , it works much better I prefer the velo with a reel, I stay with an unmodified ultimate lyrik ( air) and I find the bike top

1621149298286891435028370635236.jpg
 

Fatbap

Well-known member
Feb 15, 2020
153
150
Rhondda south wales
I have lost a little weight but still 270-280pounds
I spoke to Yt an fox before buying my decoy 19 mullet they both said yes the bike an suspension will be fine
My rear x2 is on 320-330 psi with 3 blue volume spacers an rides great for me. Silverfish/mojo suspension told me the shock is recommended up to 350psi but will take way way over that they get tested to something like 700psi
 

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
my 2nd is also mounted in spring with the ultimate lyrik my wife finds it better with the spring also

@Poupy - Ok, reality check then if you're 220# at 300PSI, my 330PSI for 270# kitted weight sounds totally reasonable.
Really though, it sounds like DPX2 is the wrong shock for a bike as progressive leverage ratio as the Decoy is.

Do you find with the coil you get much better small bump compliance than with DPX2?
Are you seeing any sacrifice in mid-stroke support or is it all upside with the coil for you and the wife?
 

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
I have lost a little weight but still 270-280pounds
I spoke to Yt an fox before buying my decoy 19 mullet they both said yes the bike an suspension will be fine
My rear x2 is on 320-330 psi with 3 blue volume spacers an rides great for me. Silverfish/mojo suspension told me the shock is recommended up to 350psi but will take way way over that they get tested to something like 700psi

@Fatbap - Ok so you're almost my kitted weight naked...more apples-apples. Where are you at w/ your sag %?

Do you really run your Fox X2 w/ 320-330 PSI? Fox says max on the X2 is 300psi since they were doing a ton of warranty replacements for blown X2s and bleeding money. I'm surprised your Silverfish suspension folks are recommending up to 350PSI on it. But if it's working for you that's great.
 

Poupy

Member
Mar 27, 2020
35
10
France
@Poupy - Ok, reality check then if you're 220# at 300PSI, my 330PSI for 270# kitted weight sounds totally reasonable.
Really though, it sounds like DPX2 is the wrong shock for a bike as progressive leverage ratio as the Decoy is.

Do you find with the coil you get much better small bump compliance than with DPX2?
Are you seeing any sacrifice in mid-stroke support or is it all upside with the coil for you and the wife?

The coil damper is perfect for yt decoy better for low speed, mid-stroke support, or big jumps, but driving is less fun as the bike is always glued to the ground
But is better for comfort and performance
 

Gary

Old Tartan Bollocks
Author
Subscriber
Mar 29, 2018
10,496
10,702
the internet
At 330psi, there is little suppleness left.
You can't really have super supple mtb suspension at your weight. The spring needs to be stiff just to support you therefore is harder to compress. This affects small bump compliance hugely.
Basic physics I'm afraid.

it's kind of a misconception that a coil will be more supple than an air spring throughout your shocks stroke.
They simply behave differently.
A coil spring is linear so will need the same force to move it each mm of travel whereas an air spring by it's nature is progressive and will move more in the beginning stroke and less towards the end stroke with the same force applied.
Finding your sweetspot with the air shock is key. and it's not as simple chosing a % and setting sag to match that
* frame progression also affects things but let's ignore that for now for simplicity.
 
Last edited:

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
You can't really have super supple mtb suspension at your weight. The spring needs to be stiff just to support you therefore is harder to compress. This affects small bump compliance hagely.
Basic physics I'm afraid.

it's kind of a misconception that a coil will be more supple than an air spring throughout your shocks stroke.
They simply behave differently.
A coil spring is linear so will need the same force to move it each mm of travel whereas an air spring by it's nature is progressive and will move more in the beginning stroke and less towards the end stroke with the same force applied.
Finding your sweetspot with the air shock is key. and it's not as simple chosing a % and setting sag to match that
* frame progression also affects things but let's ignore that for now for simplicity.

@Gary - I can appreciate that. Colin Champman/Lotus know a thing or two about the benefits of lightness for better handling. I was indeed wondering about the small bump compliance thing, say at the sag point, whether it's air or coil, the force should exactly equal my bodyweight+gear at the sag point. So any bump-force beyond that would be acting against 330psi or whatever Lbs/in spring at that position.

But springs aside, as it stands, my DPX2 is already wide-open for LSC/HSC and it's still damping on compression more than desirable. So bumps are pushing against some stiffer Comp. damping there too. The stock valving isn't designed with the Decoy leverage progression in mind, so more restrictive than it needs to be.

Avalanche will completely re-valve the Bomber damper for my weight, riding style, spring rate and frame progressivity. They say they completely re-do the shim stacks and valving to allow a broader compression adjustment as well as allow high-speed square edge deeper hits to actually push through the shock's travel to slow it down gradually, rather than the immediate ramp-up of an air shock.

But, yeah....heavy is always bad for good handling and always requires harder/stiffer springs. Just like trying to get an SUV to be comfortable and handle correctly. Hey Porsche, wanna design my rear bike shock?
 

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
What tyres are you running? and have you sorted out your go to PSI tire setting ?

I'm on the stock Maxxis Minion DHR II 3C EXO. I've varied w/ PSI anywhere as high as 25F/28R to 18F/22R depending on terrain, weather and laziness of checking. My usual target is around 22/25 or so.
 

HOMIE5000

Member
Feb 23, 2020
55
19
Australia
I'm on the stock Maxxis Minion DHR II 3C EXO. I've varied w/ PSI anywhere as high as 25F/28R to 18F/22R depending on terrain, weather and laziness of checking. My usual target is around 22/25 or so.
OK , So 25 psi for your weight I feel may be giving you rebound through the tire . I would look a heavier casing for the rear tire , even look look at a DHF wide trail DH casing . I would recommend no lower than 27 psi .
For your weight I think you should run the largest spacer in the shock and run 30% sag , I think you will be under the 350 max psi .
Because of the larger spacer, mid stroke compression dampening and rebound compression dampening will be effected , so I would think running the shock in " open position " would be best to get a base set up.
After doing above , I would open the rebound dampening , have no dampening . Then start adding dampening 1 click at a time . The less dampening the better on a rear shock the faster the better.
If you find you not using all the travel available go one spacer down, but keep a 30% sag rate , this will also decrease compression and rebound dampening so you may need to add more rebound dampening.
 

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
For your weight I think you should run the largest spacer in the shock and run 30% sag , I think you will be under the 350 max psi .
Because of the larger spacer, mid stroke compression dampening and rebound compression dampening will be effected , so I would think running the shock in " open position " would be best to get a base set up.
After doing above , I would open the rebound dampening , have no dampening . Then start adding dampening 1 click at a time . The less dampening the better on a rear shock the faster the better.

@HOMIE5000 - I originally rode the Decoy using ~ 270psi and would regularly go through full-travel with stock setup (no spacers).

I bought spacers and used the 2nd largest spacer (0.86 cu.in., largest recommended by Fox for 230x60mm) and 2 clicks from closed on Rebound Damping (per Fox's manual for my weight/PSI). I wasn't getting anywhere close to final 1/3 of shock travel with the dark blue spacer (largest recommended by Fox). Went down to the light blue 0.6 cu.in., but that's when my buddy loaned me his ShockWiz tuner and I realized my sag was more like 45-50% (Dynamic). Nowhere near 33% recommended. I opened up Rebound to 3-clicks from closed to get a bit more rebound speed, but it's on the cusp of being underdamped.

ShockWiz kept recommending:
1) Add air - went from 280 > 300 > 314 > 330 psi....finally Shockwiz said it was OK.
2) reduce vol. spacers - I'm currently down to the smallest 0.20in^3 Purple spacer
3) soften LSC and HSC - I always run the blue 3-way in "open". I've already opened up wide the LSC open-mode adjustment. But still, according to ShockWiz, it's not soft enough. This is due to stock valving which is inaccessible without rebuild.

I'm finding just the opposite about using volume spacers, they seem unnecessary with the proper 330psi and sag. I find I'm not bottoming out, even with the smallest spacer. I could probably go back to stock (no spacer) and not bottom out. Again, I think the Decoy leverage progression rules here. I was using spacers as a band-aid fix for incorrect sag and too-little PSI.

I'll try running harder tires and >25psi. That will reduce the undamped 'bounce' from the tire flex and put the forces up through the shock where it can be damped. Good suggestion to try. I personally felt like it made the rear very 'chattery' with higher pressures, but it's worth a revisit.

RE: Rebound damping. I'm just too heavy and 330psi too high to go below 3 clicks from closed. Rebound is easy to nail and very obvious when it's wrong. Fox's manual was spot-on here, maybe a little over damped. But I'm confident either 2 or 3 from closed is right (and makes ShockWiz happy as well). 1 from closed is a bit 'dead'. But I've got 2 usable clicks of adjustment for different terrain.
 

Fatbap

Well-known member
Feb 15, 2020
153
150
Rhondda south wales
@Fatbap - Ok so you're almost my kitted weight naked...more apples-apples. Where are you at w/ your sag %?

Do you really run your Fox X2 w/ 320-330 PSI? Fox says max on the X2 is 300psi since they were doing a ton of warranty replacements for blown X2s and bleeding money. I'm surprised your Silverfish suspension folks are recommending up to 350PSI on it. But if it's working for you that's great.

Runnin 30% sag mate I have no issues whatsoever an bike feels amazing. Just because it says max 300 mate mine is above that I know as I said they get tested way above it
An when I spoke to silverfish a few years back regarding shocks air vs coil they said I won’t get a spring for my weight an air would be much better for me.
I found setting my bike up a bit of piss was surprised how quickly I got it dialled in an I never complain about my suspension settings at all
Oh an lately I’ve been running the flip chip in low no complaints from me
 
Last edited:

HOMIE5000

Member
Feb 23, 2020
55
19
Australia
@HOMIE5000 - I originally rode the Decoy using ~ 270psi and would regularly go through full-travel with stock setup (no spacers).

I bought spacers and used the 2nd largest spacer (0.86 cu.in., largest recommended by Fox for 230x60mm) and 2 clicks from closed on Rebound Damping (per Fox's manual for my weight/PSI). I wasn't getting anywhere close to final 1/3 of shock travel with the dark blue spacer (largest recommended by Fox). Went down to the light blue 0.6 cu.in., but that's when my buddy loaned me his ShockWiz tuner and I realized my sag was more like 45-50% (Dynamic). Nowhere near 33% recommended. I opened up Rebound to 3-clicks from closed to get a bit more rebound speed, but it's on the cusp of being underdamped.

ShockWiz kept recommending:
1) Add air - went from 280 > 300 > 314 > 330 psi....finally Shockwiz said it was OK.
2) reduce vol. spacers - I'm currently down to the smallest 0.20in^3 Purple spacer
3) soften LSC and HSC - I always run the blue 3-way in "open". I've already opened up wide the LSC open-mode adjustment. But still, according to ShockWiz, it's not soft enough. This is due to stock valving which is inaccessible without rebuild.

I'm finding just the opposite about using volume spacers, they seem unnecessary with the proper 330psi and sag. I find I'm not bottoming out, even with the smallest spacer. I could probably go back to stock (no spacer) and not bottom out. Again, I think the Decoy leverage progression rules here. I was using spacers as a band-aid fix for incorrect sag and too-little PSI.

I'll try running harder tires and >25psi. That will reduce the undamped 'bounce' from the tire flex and put the forces up through the shock where it can be damped. Good suggestion to try. I personally felt like it made the rear very 'chattery' with higher pressures, but it's worth a revisit.

RE: Rebound damping. I'm just too heavy and 330psi too high to go below 3 clicks from closed. Rebound is easy to nail and very obvious when it's wrong. Fox's manual was spot-on here, maybe a little over damped. But I'm confident either 2 or 3 from closed is right (and makes ShockWiz happy as well). 1 from closed is a bit 'dead'. But I've got 2 usable clicks of adjustment for different terrain.
I would start again .
Perhaps in the "low" chip setting putting more of your body weight over the centre on the bike .
Take all the spacers and air out ,.
Then ,,Add air and cycle the shock as you are adding air equalising the air sleeve ,
Get the sag right30-33% . If your clipping pedals at 33% bring the sag back to 30%
Use the "medium" : setting on the compression dampening knob.
Ride the bike and identify what it's doing . Sag and bottom out will be the fist observation.

"ShockWiz kept recommending:"
1) Add air - went from 280 > 300 > 314 > 330 psi....finally Shockwiz said it was OK.
2) reduce vol. spacers - I'm currently down to the smallest 0.20in^3 Purple spacer
3) soften LSC and HSC - I always run the blue 3-way in "open". I've already opened up wide the LSC open-mode adjustment. But still, according to ShockWiz, it's not soft enough. This is due to stock valving which is inaccessible without rebuild.
What shock wiz is telling you is ,
!/ at 330psi your sag is right
2/ bottom out resistance is too firm reduce air volume spacer .
3/ the currant air volume spacer is dampening the LSC and HSC effecting small bump sensitivity and traction.
As you can see spacers effect bottom out resistance , spacers also add dampening to LSC HSC and rebound.

max psi is 350 for the shock , so I feel you should be able to get it right . Perceiver they are very good shocks

Are you blowing you feet off you'r pedals ?
 

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
Use the "medium" : setting on the compression dampening knob.

"ShockWiz kept recommending:"
2/ bottom out resistance is too firm reduce air volume spacer .
3/ the currant air volume spacer is dampening the LSC and HSC effecting small bump sensitivity and traction.
As you can see spacers effect bottom out resistance , spacers also add dampening to LSC HSC and rebound.

max psi is 350 for the shock , so I feel you should be able to get it right . Perceiver they are very good shocks

Are you blowing you feet off you'r pedals ?

#1) Why would you recommend raising HSC damping when ShockWiz recommends making it softer and I'm already running into compliance issues? The only thing the middle compression knob helped with was reducing bottom out and g-out issues when I was over-sagged (260 psi), but that shouldn't be a fix for incorrect PSI from what I've read everywhere.

#2) I should clarify that ShocWiz was finally all 'good' / green (no suggestion) with the current smallest purple volume spacer. It did not say to remove it. That said, I may remove it anyway due to the progression of the frame - it's probably redundant. YT ships DPX2 empty...so spacers just exacerbate the issue.

#3) I can only imagine the smallest spacer influencing LSC/HSC if I were well into the ramp-up of the pressure curve (60-75+% travel). My suspicion is that a baseline high-PSI is causing the lack of sensitivity (rather than the minimal spacer), and I think removing the spacer may end up with the same situation at 330psi. I'll test to find out.

Funny you mention the feet. I did notice that they are coming off the pedals sometimes...more than before. Even though I'm trying to keep the rebound as fast/poppy as safely possible.
 

HOMIE5000

Member
Feb 23, 2020
55
19
Australia
#1) Why would you recommend raising HSC damping when ShockWiz recommends making it softer and I'm already running into compliance issues? The only thing the middle compression knob helped with was reducing bottom out and g-out issues when I was over-sagged (260 psi), but that shouldn't be a fix for incorrect PSI from what I've read everywhere.

#2) I should clarify that ShocWiz was finally all 'good' / green (no suggestion) with the current smallest purple volume spacer. It did not say to remove it. That said, I may remove it anyway due to the progression of the frame - it's probably redundant. YT ships DPX2 empty...so spacers just exacerbate the issue.

#3) I can only imagine the smallest spacer influencing LSC/HSC if I were well into the ramp-up of the pressure curve (60-75+% travel). My suspicion is that a baseline high-PSI is causing the lack of sensitivity (rather than the minimal spacer), and I think removing the spacer may end up with the same situation at 330psi. I'll test to find out.

Funny you mention the feet. I did notice that they are coming off the pedals sometimes...more than before. Even though I'm trying to keep the rebound as fast/poppy as safely possible.
The shock should be set up in the " medium setting " if you are removing all the spacers as I suggested as a base setting start up, and setting up a less aggressive rear shock and softer platform as a base line, The "medium " setting is a balance of LSH & HSC . If the shock is on " firm " the LSC dampening is being added better pedalling platform and less supple . Alternatively if the shock is in "soft " dampening on the LSC & HSC has been removed the bike will track better more supple .
Any volume spacers effect the shocks dampening especially the "mid" stroke . The reason why air shocks are so good , is air volume spacers increase mid stroke firmness giving a more aggressive / firmer platform.Yes the spacers on air shocks effect the bottom out , but the mid stroke is effected far greater. <As an exercise , place all the spacers you have in the shock and you will notice the rebound on the shock will be slower/ damper >
You are blowing your feet off the pedals because your rebound is too slow .
I feel folk governs pop through LSR and LSC far greater than the rear shock LSC &HSC . Less rebound dampening on the rear shock ads the fork and the bike.
If you have time, just try what I have suggested.
Start from scratch , no spacers , the right sag 30-33% , "medium " shock position , a well cycled rear shock and the bike in the low chip setting . Start there as your base and identify what the rear shock is doing.
By putting the bike in " LOW" chip setting the fork will perform differently.
 

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
The shock should be set up in the " medium setting " if you are removing all the spacers as I suggested as a base setting start up, and setting up a less aggressive rear shock and softer platform as a base line, The "medium " setting is a balance of LSH & HSC . If the shock is on " firm " the LSC dampening is being added better pedalling platform and less supple . Alternatively if the shock is in "soft " dampening on the LSC & HSC has been removed the bike will track better more supple .
Any volume spacers effect the shocks dampening especially the "mid" stroke . The reason why air shocks are so good , is air volume spacers increase mid stroke firmness giving a more aggressive / firmer platform.Yes the spacers on air shocks effect the bottom out , but the mid stroke is effected far greater. <As an exercise , place all the spacers you have in the shock and you will notice the rebound on the shock will be slower/ damper >
You are blowing your feet off the pedals because your rebound is too slow .
I feel folk governs pop through LSR and LSC far greater than the rear shock LSC &HSC . Less rebound dampening on the rear shock ads the fork and the bike.
If you have time, just try what I have suggested.
Start from scratch , no spacers , the right sag 30-33% , "medium " shock position , a well cycled rear shock and the bike in the low chip setting . Start there as your base and identify what the rear shock is doing.
By putting the bike in " LOW" chip setting the fork will perform differently.

I'll check out zero spacers, but the only thing I question is the 'medium' compression setting when Shockwiz is telling me just the opposite (Soften HSC/LSC) even in the "Open" setting (and the open LSC channel wide open too).

Won't the 'medium' setting be firmer for both? I've almost never used "firm" except on streets trying to hustle back to the car. I ride in "open" 95% of the time.

Also, Fox (and others) recommend setting sag in "Open". Am I reading correctly that you're suggesting set sag in "Medium"?
If so, why?
 

HOMIE5000

Member
Feb 23, 2020
55
19
Australia
I'll check out zero spacers, but the only thing I question is the 'medium' compression setting when Shockwiz is telling me just the opposite (Soften HSC/LSC) even in the "Open" setting (and the open LSC channel wide open too).

Won't the 'medium' setting be firmer for both? I've almost never used "firm" except on streets trying to hustle back to the car. I ride in "open" 95% of the time.

Also, Fox (and others) recommend setting sag in "Open". Am I reading correctly that you're suggesting set sag in "Medium"?
If so, why?
The compression dampening wont effect the sag. Desired sag can be reached in soft medium or hard .
Sag effects the travel & shocks stroke . LSC HSC and all dampening is the restriction of the stroke of the shock.
Shock wiz is telling you , because you have spacing the spacing is enhancing the dampening.
The medium setting will give you a more supportive peddling platform less traction , less supple fell and is desirable for lower speed or aggressive trail riding.
The open setting is for higher speeds , will give less LSC less HSC more traction and bottomless feel .
So my suggestion of "starting " with no spacers sag at 30-33%, medium setting , is a slightly restricted shock via the HSC &LSC only , you can move to "open ". You will be sacrificing peddling platform , but you may not need it . Just see how the bike goes.
 

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
The compression dampening wont effect the sag. Desired sag can be reached in soft medium or hard .
Sag effects the travel & shocks stroke . LSC HSC and all dampening is the restriction of the stroke of the shock.
Shock wiz is telling you , because you have spacing the spacing is enhancing the dampening.
The medium setting will give you a more supportive peddling platform less traction , less supple fell and is desirable for lower speed or aggressive trail riding.
The open setting is for higher speeds , will give less LSC less HSC more traction and bottomless feel .
So my suggestion of "starting " with no spacers sag at 30-33%, medium setting , is a slightly restricted shock via the HSC &LSC only , you can move to "open ". You will be sacrificing peddling platform , but you may not need it . Just see how the bike goes.

@HOMIE5000 - in the name of Science...I just had to go collect some more data this morning. ;)

I rode the same 4 mile loop that has a good mix of my 'average' ride terrain using "MIDDLE" and then "OPEN" on the blue 3-pos HSC adjustment. Per your instructions, I removed the last purple spacer. I also inflated tires to 25F/27R (they were just 2 psi lower). Rebound was at 3 clicks from closed based on my experience. 33% static sag @ about 333 psi. This was a true A/B test (except for order effect) - nothing else was changed between comparisons. ShockWiz had start new session before each and was at 99% confidence in their suggestions for "Neutral-Poppy". They didn't change much if I selected "Neutral-Planted".

I find the data surprising...and definitely not what I'd assume.

COMPRESSION: Using "MIDDLE", I would have expected HSC/LSC to be in the yellow or maybe even red based on how the bike felt. In "OPEN" setting, curiously, the HSC/LSC went yellow again to "make softer". Very contrary to my subjective observations.

REBOUND: "Slow Down" for both....I should probably run 2 clicks from closed Rebound damping on that trail. Others with playful rollers, I'd run 3 clicks from closed.

POGO: "Poor" for both. Ditto on Rebound fix.

Other Surprises:
  • Baseline Pressure: "MEDIUM" says "add air". "OPEN" says "OK". Huh? Should be the same. Or maybe "add air" for the "OPEN" setting if anything. Seems contrary to my assumptions.
  • Air Spring Ramp: "Medium" says "Remove Spacers", but "Open" does not. Not what I'd expect again.
  • Dynamic Sag: Medium-setting @ 41%; "Open" was 37%. Also contrary to intuition. I take this metric with a grain of salt because I don't think it's calculated over the whole data collection period, but rather the most recent 20 pedal inputs.
SUBJECTIVE:
Running in "Medium" isn't for me on my trails. In the past, I've ridden the Medium setting before as a temporary fix for improperly set sag @ 260psi. It was harsh, busy, noisier, and lots of carbon frame 'ticking' sounds. Supportive as heck (I literally felt like I was riding higher). It felt like a perfect setting for a pump track. But it was scary going my typical speeds down some gnarly stretches. If anything, my feet left the pedals more-often in this setting than in Open-setting. Usually from a larger square-edge hit, my body gets pushed up on compression, but the bike comes back down and I'm still in the air. Need more knee flexion a-la hardtail style.​
"Open" - still had some small-impact harshness that I originally bitched about, but way, way better than "Medium". I felt much more settled over progressive hits. My body motion was more stable. I found no deficits in climbing due to the more supple planted rear. I didn't really notice the Pogo issue either. I suspect 2-3 clicks from closed rebound damping is the right place for me.​
LEARNINGS?:
  • I like HSC "Open" mode better than "Medium" for my trails/style
  • I really do need 325-330 PSI for 30-33% sag
  • I don't need spacers, but removing the Purple spacer had no measurable (5%) effect on HSC/LSC
  • +/- 2-3 PSI tire pressure yields the same ShockWiz data with no measurable effect on HSC/LSC
  • A heavy rider on high-PSI sag point doesn't allow the suppleness I'm looking for with stock shock valving but completely ridable.
HSC Low vs Medium.png
 

Camstyn

Well-known member
Jun 19, 2019
121
142
Kamloops BC
Keep in mind that if you make multiple changes at once due to the shockwiz recommendations you will be chasing your tail. Always start a new session between changes, and recalibrare for compression ratio when you change PSI/spacers.

based on what you’re saying, start with 335-350psi and no spacers with a fresh calibration. Get one thing green at a time, starting at the top, and don’t jump ahead with compression/rebound. One thing at a time, first get PSI green, then new session, get spacers green, new session, and keep going down the list like that. Start by getting sag at 30%.
 

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
Keep in mind that if you make multiple changes at once due to the shockwiz recommendations you will be chasing your tail. Always start a new session between changes, and recalibrare for compression ratio when you change PSI/spacers.

based on what you’re saying, start with 335-350psi and no spacers with a fresh calibration. Get one thing green at a time, starting at the top, and don’t jump ahead with compression/rebound. One thing at a time, first get PSI green, then new session, get spacers green, new session, and keep going down the list like that. Start by getting sag at 30%.

@Camstyn - Yes, I'm on board with the 'one-adjustment-at-a-time'. I actually had the DPX2 as nailed as it could be going in order per ShockWiz's recommendations, but it was suggested by homie above that I try the "medium" HSC lever setting. So I gave it another go. Really that was the only significant change that was made above for A/B testing from my previous setup.

Using a single-adjustment per session approach, my previous efforts could never yield and All-Green ShockWiz suggestions board (ending at ~ 330 psi, 30-33% sag, no spacer, 25F/27R tire psi). HSC and LSC always end up as "make softer", but I'd have green for everything else (including no pogo or any other unwanted events). That's about as good as I can get the stock YT tune DPX2 -- which is probably fine for most folks and it is rideable. But the stock compression valving isn't really designed for the extremes of 95# and 270# riders, but rather your average 160-180 # Enduro rider.

Are you saying that just adding another 10 PSI might yield a 'softer' HSC/LSC reading? That sounds counterintuitive to me. I've got nothing to lose to test other than comfort (just like above w/ the "Medium" switch), but I'm wanting more suppleness, not less. Seems like the wrong direction.

Anyway, at this point I've laid down a deposit on getting a Bomber CR with custom Avalanche tune built up once they can get inventory. I'm hoping that will bring me the right traction, support and damping that I need.
 

Endoguru

Active member
Aug 21, 2019
142
131
Usa
I've read/re-read the tuning sticky...watch all the videos, but need some help for a heavy rider.

I borrowed my (generous) friend's Shockwiz and went down a tuning rabbit hole for the past 2 weeks and have uncovered that I'm likely too heavy for this bike frame to be running an air shock. I'm on Decoy29 Pro w/ Fox DPX2 rear shock.

I'm 270 lbs with hydration/gear, and used ~ kitted weight PSI for several months before I had access to the Wiz. Had initial pedal strikes, learned how to ride a bit better, but also put flip-chip in 'high' and bought some volume spacers. Ended up using the light-blue and thought I had things "dialed".

Along comes Shockwiz. The 36E fork was pretty easily nailed and just ended up with wide-open HSC/LSC and reduced some PSI from Fox's manual recommendations. The DPX2...not so much. After proper calibration and 100% confidence in suggestions, the Wiz recommends: Add air, reduce vol. spacers, soften LSC and HSC. Dynamic sag was near 50%. Next ride was @ 300psi/smaller spacer...same recommendations. Then 314psi/smaller spacer...same recommendations. Yesterday 330psi (!) and the smallest 0.20in^3 Purple spacer - FINALLY - Wiz stopped saying "Add air / remove spacer". But LSC and HSC are still too hard. These are the same suggestions by the way in Neutral+Poppy and Neutral+Planted, which is where I want to be.

At 330psi, there is little suppleness left. It's totally ridable and still a fun bike but the ride is very busy with lots of chatter. I'm also now sitting up pretty tall (still at ~ 38% dynamic sag though according to the Wiz), and feel like I need to flip my chip back to "low". Fox says "Shockwiz data aren't accurate for Fox products". I don't really buy that. The Wiz still collects repeatable objective data, whether or not the data are accurate, they are repeatable and it's better than the human butt-dyno. But when pushed, Fox says a custom re-valve would be required to get LSC/HSC any softer. I'm simply at the limits of adjustment on both rebound and compression. At least rebound is nailed within 2-3 clicks from closed.

I called a few revalve services places and the YT code Float DPX2 CEC001 is a bit of a mystery. Some shops warn any revalving may not change or improve the ride at all. It's a crapshoot. The NEW Float X might help a little if the predicted 40psi reduction is true, but 290psi is still a very hard air spring.

Avalanche Racing flat-out refuses to do an air shock for a Decoy client. The owner Craig says the Decoy frame leverage ratio is already so progressive that an air spring is simply the wrong type of spring to use...period. For any rider weight, in his opinion. Decoy sag requires a LOT of spring force to settle at 33% and in my case that happens to be 330psi. He predicts at that PSI, my shock is a ticking time bomb and that adding volume spacers are going the opposite direction of what's needed.

His recommendation is 650# or 700#/in coil on Bomber CR or Fox Van RC, custom revalved by his shop. Details of what they do are listed here: Fox Van Rc and Bomber CR Speed sensitive Damper SSD mods.

The cost is something like $730 for the shock, spring and custom valving . This seems very reasonable given the price of say Push 11.6 options and just a hair more than say Fox DHX2 with standard spring.

He does warn that doing a coil out back and standard Fox 36E air spring up front may be wonky and out of synch...he recommends coil on both ends.

Before pulling the trigger and waiting 3 months - I wanted to see what you other heavier riders are doing out there faced with this situation. He mentioned one other guy that's 300# on a Decoy, so I'm not the only one out there I'm sure.
  • Has anyone had experience with a re-valved DPX2 off a Decoy? Did it help?
  • Is air really the wrong spring for the Decoy?
  • Is 330 PSI really that dangerously high? (even if I'm willing to tolerate the lack of suppleness) - Craig says "it's a time bomb" while Fox says max psi is 350. I want to avoid a blown shock given COVID inventory backlogs.
  • Would the new Float X (also 350 psi max) be a better option for heavier rider, or will it be the same story since it's air-sprung?
  • Have any of you coil-converted riders looked back and missed the liveliness of your air shock?
Am I missing something or is coil the smarter way to go with this bike and my weight?

Thanks in advance all!

View attachment 61582 . View attachment 61585
I am not a Clyde (205 with gear on), but I do run an Avalanche tuned Bomber CR on my Decoy. I have had 3 shocks tuned by Craig on different bikes as well as a couple of EXT Storia shocks. Craig knows what he is doing and has gotten the tune correct every time. Nothing beats a shock custom tuned for your bike and you. The price of a Bomber and Craig’s tuning is less than any of the high end shocks and will perform better.
 

Jeffsy29

Member
May 6, 2020
191
85
Rockville MD
I am not a Clyde (205 with gear on), but I do run an Avalanche tuned Bomber CR on my Decoy. I have had 3 shocks tuned by Craig on different bikes as well as a couple of EXT Storia shocks. Craig knows what he is doing and has gotten the tune correct every time. Nothing beats a shock custom tuned for your bike and you. The price of a Bomber and Craig’s tuning is less than any of the high end shocks and will perform better.
@Endoguru
That’s great to hear that Avalanche wins return business.

what are you running up front? Any customization?
 

Endoguru

Active member
Aug 21, 2019
142
131
Usa
@Endoguru
That’s great to hear that Avalanche wins return business.

what are you running up front? Any customization?
Not yet. I’m cons
@Endoguru
That’s great to hear that Avalanche wins return business.

what are you running up front? Any customization?
Not yet. I’ve been able to get acceptable performance from the stock fork with a little fiddling. I am considering an Avalanche coil conversion for the fork, but am concerned about adding more weight to the front of the bike. I like to jump and Ebikes are already a little front heavy with the battery.
 

EMTB Forums

Since 2018

The World's largest electric mountain bike community.

555K
Messages
28,070
Members
Join Our Community

Latest articles


Top