Vorsprung Suspension Corset Fox Air Shock Upgrade

bell.cameron

Likes Dirt
Have people started receiving there stuff yet? ordered mine direct two weeks ago tomorrow but still nothing? I thought I read Express postage somewhere :/
 

Nautonier

Eats Squid
Sounds like a volume spacer could help you out quite a bit there. What bike is this on?
S-works enduro 650b. I rode it again today at Lysterfield and it was still bottoming out at 280PSI on small - medium drops, which isn't ideal. Will Brad be able to help me out with volume spacers? Are they expensive? Easy to install?
 

waldog

Likes Bikes and Dirt
S-works enduro 650b. I rode it again today at Lysterfield and it was still bottoming out at 280PSI on small - medium drops, which isn't ideal. Will Brad be able to help me out with volume spacers? Are they expensive? Easy to install?
Harsh bottom out, or just using full travel?
 

Nautonier

Eats Squid
Just a heads up to those who might be removing the Corset after its been pressurised: even letting all air out of the valve before unscrewing, I got a very loud 'bang' as the Corset rocketed away from the shock body! Must be the air trapped in the negative air chamber or something. I wonder what would happen if it was removed using the other method, ie removing the retainer ring and then sliding off the outer sleeve before the inner sleeve? I'm sure there would still be a rapid depressurisation at some point?

Wondering what size volume spacer to start with, I'm tempted to go with the thickest one to maximise ramp up, which will hopefully minimise the amount of air I have to put in it to stop it bottoming. Very soon I might have air shock perfection!
 

DeBloot

Feeling old
I vote for medium.
Steve from Vorsprung suggested a medium to me
They will send 3 sizes if you order them so you can go either way from medium

On this topic, what are the NEGATIVES, if any, of using spacers (volume reducers)
 

Nautonier

Eats Squid
Turns out I didn't have a lot of choice; I was sent a kit of 5 spacers and only 2 of them fitted my shock without reducing the travel of the shaft (I assume that spacers which don't allow the bumper/washer to reach the black housing at the end of the shaft will do this). I used the second-smallest one, which appeared to be about 9mm. I've gone from 280PSI down to 240 and the ramp-up seems to be much better on a quick bounce, but the trail test will reveal more. Still getting a lot of sag though, around 35% at least.
 

Ivan

Eats Squid
Steve from Vorsprung suggested a medium to me
They will send 3 sizes if you order them so you can go either way from medium

On this topic, what are the NEGATIVES, if any, of using spacers (volume reducers)
Apart from the changes to spring curve, one issue I see would be that the smaller volume of air will heat up quicker.

I run a volume spacer in a non-vorsprunged RP23 and love the changes.
 

Nautonier

Eats Squid
I heard a rumour (from a bike mechanic in NZ) that the Corset design will be stock on all 2016 Fox shocks, can anyone confirm or deny this?

9mm spacer still not enough, I'm going the next size up. Still had to run 270PSI on todays ride to stop harsh bottom outs. The Enduro 27.5 must have a hell of a leverage ratio to push the shock that hard at the end of its travel.
 

Ivan

Eats Squid
Fox do have something similar under development. When it gets put into production is anyone's guess.
 

willsy01

Eats Squid
Question for Steve if he's around (or anyone else that's cluey with suspension).......how well would the corset go on a Commencal Meta AM?

My understanding is that it's got quite a high leverage ratio (about 2.6:1. 150mm travel, 57mm stroke). I'm currently running about 190psi in a standard volume Float CTD so i'd say it will be skirting the upper end of the air pressure capabilities.
 

Nautonier

Eats Squid
I can't seem to find published figures on the Enduro's leverage ratio, is it just the travel divided by the shock stroke? If this is the case it has a leverage ration of about 3:1. Not knowing anything about suspension, is this considered high or low?

I've read that the Enduro is very linear in its leverage, perhaps this would explain why it's having so many issues ramping up with the Corset, although reading Steve's post it was suggested that the Corset wouldn't change this over the Fox air sleeve characteristics (which weren't a problem).

I'm hoping that just going up and up with the volume spacers will eventually fix the problem.
 
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Rhys_

Likes Bikes and Dirt
The numbers you guys are quoting are average leverage ratios. The main implication is spring rate.

A leverage ratio diagram for your frame will show how the leverage ratio varies through the travel. This will tell you more about how the linkage behaves and help you understand how and why your frame and shock behave in certain ways.
 

S.

ex offender
Hi guys - for future reference, email me on steve at vorsprungsuspension dot com rather than posting here, I don't always have time to check forums sorry!

Question for Steve if he's around (or anyone else that's cluey with suspension).......how well would the corset go on a Commencal Meta AM?

My understanding is that it's got quite a high leverage ratio (about 2.6:1. 150mm travel, 57mm stroke). I'm currently running about 190psi in a standard volume Float CTD so i'd say it will be skirting the upper end of the air pressure capabilities.
2.6:1 is pretty standard, definitely not considered high. If you're running 190psi you should have no issues, if you're running the standard volume Float sleeve you may want to experiment with adding air volume spacers too though.

I can't seem to find published figures on the Enduro's leverage ratio, is it just the travel divided by the shock stroke? If this is the case it has a leverage ration of about 3:1. Not knowing anything about suspension, is this considered high or low?

I've read that the Enduro is very linear in its leverage, perhaps this would explain why it's having so many issues ramping up with the Corset, although reading Steve's post it was suggested that the Corset wouldn't change this over the Fox air sleeve characteristics (which weren't a problem).

I'm hoping that just going up and up with the volume spacers will eventually fix the problem.
3:1 is fairly high for trailbikes yes. The overall leverage ratio dictates the air pressures you'll have to run at a given weight, whereas the leverage rate curve is what dictates how much ramp up you'll need. In the case of the Enduro, it requires fairly strong ramp-up from the shock because the ending stroke is quite digressive, and because the small diameter Corset runs a slightly larger volume than the large diameter one in the same size (the large diameter one is constrained in that regard), you'll want to run a larger volume spacer (it is also possible to add volume spacers to the outside of the small diameter sleeves using 40.00 x 2.00mm o-rings, make sure they're only over the positive chamber part though).

With the large diameter sleeves you can usually just plug and play, the small diameter ones you can in some circumstances but in the Enduro you'll need a reasonably large volume spacer as their stock air sleeve actually isn't a standard sleeve - that bike is the only one using a shock that long with a small volume eyelet as stock. The 2010-12 Enduros had a custom sleeve also.
 

S.

ex offender
Just a heads up to those who might be removing the Corset after its been pressurised: even letting all air out of the valve before unscrewing, I got a very loud 'bang' as the Corset rocketed away from the shock body! Must be the air trapped in the negative air chamber or something. I wonder what would happen if it was removed using the other method, ie removing the retainer ring and then sliding off the outer sleeve before the inner sleeve? I'm sure there would still be a rapid depressurisation at some point?

Wondering what size volume spacer to start with, I'm tempted to go with the thickest one to maximise ramp up, which will hopefully minimise the amount of air I have to put in it to stop it bottoming. Very soon I might have air shock perfection!
If all the air is dumped from the sleeve rapidly, the shock will compress itself (a la a "stuck down" shock) as the piston passes the equalisation port faster than the air pressure can actually equalise, which results in the negative chamber remaining pressurised and the experience you had with it blowing off. To prevent this, release air slowly using a shock pump. A short distance into the travel, you'll hear a faint clicking noise, this is the air equalising. If it gets too far into the travel, you'll need to either extend the shock by pumping it back up a bit, or if it's still in the bike, forcibly extending the suspension slightly.

Instructions for removal are found down the page a bit here: http://www.vorsprungsuspension.com/pages/corset-air-sleeve-installation-setup

Setup notes on that page are an evolving work - as we get more and more feedback from riders on different frames, we can offer more specific advice on those bikes.
 

Nautonier

Eats Squid
If all the air is dumped from the sleeve rapidly, the shock will compress itself (a la a "stuck down" shock) as the piston passes the equalisation port faster than the air pressure can actually equalise, which results in the negative chamber remaining pressurised and the experience you had with it blowing off. To prevent this, release air slowly using a shock pump. A short distance into the travel, you'll hear a faint clicking noise, this is the air equalising. If it gets too far into the travel, you'll need to either extend the shock by pumping it back up a bit, or if it's still in the bike, forcibly extending the suspension slightly.
Thanks Steve, worked a treat and no explosion with parts ricocheting off the fence this time!
 
Z

Zaf

Guest


18hrs before my flight, it arrives. Oh well, toys to play with when I get home.
 
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