Jeffsy29
Member
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.
Thanks in advance all!
.
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?
Thanks in advance all!
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