http://www.tftuned.com/vorsprung-corset-air-sleeve/p3135

So who has one and has it been a big improvement to your Fox shock?
I have one on preorder after reading reviews and am a little disappointed with the performance of my FOX Float X. Large volume reducer helps with the midstroke blow through, but it feels a little “dead” now.

Very interested in these. I have the same thing with my Float X, cant quite get it spot on.

Is it just me or are we being conned into paying top dollar for suspension that seemingly doesn’t work the way it should or is rushed to market half finished and then requires further expense and tinkering in the form of modified air sleeves, plastic tokens etc etc….how about Fox or Rockshox actually release a product that works without this kind of modification and had dials that adjust the suspension in a noticeable way so mere mortals can tune their own bikes without the need for ‘corsets’ and ‘bottomless tokens’!?

….or just go back to coil shocks and be done with it as just about every one of these gimmicks claim to offer ‘coil like’ performance as part of their blurb.

I got my float tuned by Loco, made a world of difference. If your not Mr Average I would recommend a proper tune.

I feel the same deviant. I’m not sure who these Fox shocks are tuned for from factory, but it seems everyone has issues with them. I suppose there are loads of different frame designs to cater for and some may bring out the worst in the shock, but you’d think the frame designers wouldnt spec the shock then!
My last RP23 needed a shim fitted almost as soon as I got the frame, fortunately it was homemade so didnt cost much and performed very well. The float x costs a bomb, you’d think it would be better..

Alternativley

Is it just me or are we being conned into paying top dollar for modified air sleeves, plastic tokens etc. etc. to tinker with suspension that works perfectly well in the first place

Is custom shock tuning the homeopathy of the mountain bike world?

Large volume reducer helps with the midstroke blow through, but it feels a little “dead” now.

Hang on, is the point of the vorsprung not that it gives you *more* volume, but you like your shock with less?

Hang on, is the point of the vorsprung not that it gives you *more* volume, but you like your shock with less?

I like my shock to not blow through the travel so easily, which it was doing with standard reducer. The large reducer ramped up the travel, understandably, as it reduced the volume of air, so meant I wouldnt reach the end of travel so easily. The Corset is meant to provide a more linear spring rate, more like a coil, yet it will ramp up towards the end.

ninfan – Member
Alternativley
—–
Is custom shock tuning the homeopathy of the mountain bike world?

I see what you did there 🙂

for a lot of riding standard tunes are fine, it only really matters when you are asking a lot of the rear shock [whispers] enduro [/whispers] for example you want a shock that pedals well but then very controlled on the super gnar, techy, hero descents
superfi and many others are racing enduro and DH on 160mm bikes with air shocks, this highlights the shortcomings of a lot of them, yeah a nicely setup coil would probably be better suited to the dh but thats double the weight and not so much fun on the climbs!

I’m quite interested to hear the results on this too, the CTD shock I have suffers the same issue, was thinking about a tune but this ‘sounds’ good too

This explains it well:

http://linkagedesign.blogspot.co.uk/2015/02/vorsprung-corset-air-sleeve.html?m=1

(with google translate!)

Got mine, works really well. Surprisingly ( to me anyway) it makes my bike climb better, as well as descend better.

Have a read of this thread here

I like my shock to not blow through the travel so easily, which it was doing with standard reducer. The large reducer ramped up the travel, understandably, as it reduced the volume of air, so meant I wouldnt reach the end of travel so easily. The Corset is meant to provide a more linear spring rate, more like a coil, yet it will ramp up towards the end.

One of us doesn’t understand the concept of air can reducer spacers. I’m not sure how to break this to you, but…

P1V1 = P2V2
Pressure is proportional to spring rate at a given point in the cycle

Air shocks will necessarily ramp up towards the end of travel, but they can do this to a lesser extent (I.e. become more linear) by utilising a bigger air can. If you have more volume but the same initial pressure, the initial movement of the shock will be unchanged but the shock won’t ramp as much and you’ll bottom out easier. So more volume = more linear stroke.

There is no air volume adjuster that does anything other than increase or decrease the volume of the air cans and relative ratio of positive to negative chamber volume. Crucially, they can’t affect pressure at various points in the shock cycle. Manufacturers would love to be able to tune the spring rate at any point in the shock travel. It’s just not possible with the technology we have*.

The only thing they (Vorsprung) can potentially offer is by reducing the initial stiction of the air can seal, you can run a higher pressure at the beginning of the stroke and overall the initial force required to move the shock (AKA small bump compliance) stays the same. But because you’re running higher initial pressure, you can have a larger can with a more linear feel, without bottoming out. This is possibly what they are professing to offer. And yet they say they use Fox seals.

So if you believe the hype, you basically have to believe that over years of making shocks, Fox can’t do simple back-of-envelope calculations about how to optimise the spring rates. This is basically their whole business, I can’t believe they would get it fundamentally wrong. Of course, some people are statistical outliers and Fox can’t make shocks that are perfect for everyone in every situation. But I bet they get it right most of the time.

Personally, I think these things are snake oil and you’d have to be pretty gullible to believe their promises which are basically all the suspension marketing buzz words thrown into a paragraph without a single moment’s hesitation. Shameless.

Coil-like feel and spring rate
Better small bump compliance
More mid-stroke support – no more wallowing
Plusher, slipperier feel
Superior traction
Bottomless big-hit feel
Predictable jumping characteristics

They do look cool though, so there’s a reason to buy one.

*Fox did actually attempt this with their DRCV setup on Treks a few years ago. They no longer offer this though.

You do realise that within 2 days of the corset being launched Fox announced their own version based on prototypes seen last year? Seems like one of them is doing something right/wrong

“From the PB comments:

VorsprungSuspension (7 hours ago)
It’s all to do with the ratios and volumes of positive and negative chambers, and where they equalise. By manipulating those values, we can change the rate at which the negative spring pressure drops early in the travel, which is what controls the early stroke and is really the defining point of these sleeves. It doesn’t affect the damping – that is completely separate.
”

Air shocks will necessarily ramp up towards the end of travel, but they can do this to a lesser extent (I.e. become more linear) by utilising a bigger air can. If you have more volume but the same initial pressure, the initial movement of the shock will be unchanged but the shock won’t ramp as much and you’ll bottom out easier. So more volume = more linear stroke.

This is what I was saying. Fitting the large reducer, gave the shock less air space and ramped up quicker, so stops me reaching the end of travel so easily. However, it makes the shock feel a little wooden.

Snake oil you say? Maybe I shouldnt have read independent reviews on MTBR and various websites, plus skydragon and somehow manage to get a demo of one. Funny how Fox have cottoned on and have very similar prototypes in the pipeline….
http://www.pinkbike.com/news/sneak-peek-fox-prototype-air-shock.html

fox proto

http://www.pinkbike.com/news/sneak-peek-fox-prototype-air-shock.html

corsett

@superficial – I can believe that Fox make products that can be improved upon. Just because they are a world leader in bike suspension doesn’t mean they don’t also turn out some products that are mediocre, built to a cost and with room for improvement.

It’s a bit like saying Vauxhall make motor cars that can’t be improved on…. or Apple won’t make a sports watch which relies on the GPS of a phone which doesn’t work at low temperatures…. making it not much use at all for some sports activities 😉

It’s not rocket science and all Vorsprung have done is found a simple way (like the Debonair air can upgrade) of improving the standard shock performance.

Let’s not get too hung up that the corset will miraculously provide a cure all and somehow also in the process make you a better rider. For me, it’s made my rear shock feel a load better and I’ll settle for that thanks.

Is it just me or are we being conned into paying top dollar for suspension that seemingly doesn’t work the way it should or is rushed to market half finished and then requires further expense and tinkering in the form of modified air sleeves, plastic tokens etc etc….how about Fox or Rockshox actually release a product that works without this kind of modification and had dials that adjust the suspension in a noticeable way so mere mortals can tune their own bikes without the need for ‘corsets’ and ‘bottomless tokens’!?

If mountain bikers got it into their pea sized brains that it’s better to have basic suspension tuned for your weight and bike, than buying forks and shocks with 3-4 different damping adjustments but a shim stack that’s setup for your average rider….then yeah…..mountain bikers might not be conned.

Getting your shock tuned by loco, mojo, tf, jtech, avalanche etc is defo worthwhile, as is using volume reducers to stop a shock bottoming out
And the corset is something different altogether , no idea how it works, some sort of -ve spring?, but reducing breakaway/ stiction at the start of travel sounds good to me !

Fitted, just need to ride it

Instructions are a little off ie 3 orings rather than 4, and I think they mentioned inner rather than outer somewhere. A few diagrams would have helped.

Anyway, PSI increased 40psi and dropped reducers by 2 sizes. Riding Sunday to test. Looks classy 🙂

Glad you said that about the orings, was scratching my head for a bit

Within 10m of trail, I could feel the difference today! Most definitely more sensitive to the trail. I suppose that could be because I have dropped 2 sizes of reducer, but it doesnt blow through the travel! After my usual trails, I still had about 5mm of shock left.
I up’d the pressure to 50psi more than previous BTW. 230PSI now, instead of 180.

Very very pleased with this cheap’ish (£80) upgrade 8)

Not sure why anyone would complain about air volume spacers/ bottomless tokens being available- ZOMG we’re being given more options! It’s not a sign that the suspension doesn’t work right out of the box- not everyone wants their suspension to work the same. It’s like complaining that you have adjustment dials, or that your pump doesn’t always inflate tyres to 40psi.

^This

This sleeve fixes an issue that is common to pretty much all air shocks namely the high initial rate, tuning won’t fix it.

Rockshox brought out the Debonair, Fox the evol and Vorsprung the Corset, no snake oil involved, it’s a genuine advance in air shock technology.

Some useful info below.

Hey mate, Steve from Vorsprung here. Sorry for the slow reply to emails – trying to reply to hundreds of them within a few days!

So let’s discuss the effect of different leverage rates, and how the stock sleeve and the Corset each work with them. Let’s consider that there are basically four main variants of leverage rate curve that exist on modern bikes:

LEVERAGE RATE CURVE TYPES:
1. Linear – no substantial change in leverage ratio throughout the travel. Example – Yeti SB66C.
2. Progressive only – leverage ratio drops throughout the travel. Example – Rocky Mountain Altitude; lots of DH bikes.
3. Progressive to linear/digressive – leverage ratio drops throughout the first 2/3 of the travel, then either flattens out or increases again towards the end of the travel. This is THE MOST COMMON leverage rate found on bikes designed around air springs. Example – Specialized Stumpy/Enduro, Banshee Rune, Pivot Mach 6, Ibis Mojo HD.
4. Digressive-linear-progressive – leverage ratio INCREASES (this is known as a falling rate because the spring rate at the wheel falls, not because the leverage rate falls), flattens out (linear) then drops again (progressive). Examples – pretty much all VPP bikes where the shock is driven off the top link; Nomad/Tracer/Bronson/Carbine/Blur/etc.

Let’s also consider the characteristics of an air spring in general: they are Digressive (starts stiff, gets softer) to Linear (stays soft) to Progressive (starts soft, gets stiff). That characteristic exists on all current air springs (DRCV being a semi-exception… long story for another day) to some degree. The Corset and the Debonair both have a far less extreme version of this than the stock Fox sleeves, but it’s still there as you can see from the spring rate curve graph posted a few pages back.

Anyway, let’s look at how each of the previously mentioned leverage rates works with each of the Fox and the Vorsprung spring curves:

1. LINEAR leverage rate aka constant leverage ratio (note that the words rate and ratio are not interchangeable; ratio is a number at a given point in the travel, rate refers to the shape of the curve).
Resultant wheel spring curve with Fox spring: same shape as the Fox spring curve, just multiplied by a constant number (scales it up/down) which is the leverage ratio. This means you end up with a falling rate (stiff but becoming soft) initial stroke, a low spring rate (soft) in the mid stroke, and an increasing spring rate (soft but becoming stiff) at the end of the stroke. Initial stroke is stiff, meaning low sag, which can be good for climbing geometry because it keeps the seat tube steeper and more weight on the front wheel. Mid stroke is soft, which usually means people want that to be stiffer for descending support, which in turn makes the initial stroke even stiffer and harsher. End stroke can be tuned by volume spacers to achieve whatever ramp you need to prevent frequent bottom out, but running suspension too soft and relying on sudden end stroke ramp creates harshness too because you end up just running into a wall of resistance.
Resultant wheel spring curve with Corset: same shape as the Corset spring curve. Compared to the Fox spring curve, far softer initially and firmer in the middle. Once again, end stroke can be tuned with volume spacers to achieve whatever ramp-up you need. This means you run more sag (can be bad if you already have a bike with a slack seat tube angle (eg SB66) and climb a lot of steep stuff (the kind of stuff where you’re just about breaking your shifter trying to find an easier gear that doesn’t exist… pretty well all the climbs in Whistler!) because the front wheel will try to lift up more. On most bikes the difference isn’t anywhere near that much though, because despite running more sag, the mid stroke spring rate is quite a bit stiffer, so the settle point when your weight is shifted backwards is closer to what you’d get with the Fox sleeve. Descending, more sag gives more traction, firmer mid stroke means more support on bigger hits and compressions as well as a more predictable and lively feel.
Net result: Unquestionable improvement here, in my honest opinion.

2. PROGRESSIVE (only) leverage rate:
Resultant wheel spring curve with Fox sleeve: high initial leverage helps somewhat to overcome the stiff initial air spring feeling, but unless it’s progressive enough, the mid-stroke is still very soft – and if it IS that progressive then it ends up ramping like crazy at the end of the travel. Cross multiply the progressive end stroke of the leverage rate with the progressive spring curve of the air shock, and you’re either going to have something that sits at excessively high sag or makes it far too difficult to use full travel. Basically, progressive end strokes don’t mix well with air shocks, it’s very hard to get them sorted in such a way that the mid stroke is sufficiently supported without crazy end stroke ramp, although they do feel reasonably good off the top of the travel usually. That said, no frame I’ve ever examined has been anywhere near as progressive in the early stroke as a Fox air spring is DIGRESSIVE in the same travel – to do so you’d have to have the leverage ratio drop by at least a factor of five in the first 15mm of the travel, which would mean your leverage ratio probably starts at about 15:1… this is also very bad (gen 1 V10 had something almost like that) and it causes a lot of play at the start of the travel due to the immense leverage on both pivots and shock.
Resultant wheel spring curve with Corset: High initial leverage ratio combined with relatively linear spring curve provides very plush feel initially, mid-stroke support somewhat better, end stroke still over-supported and hard to use full travel – Corset can’t fix that.
Net result of the Corset: Better small bump absorption, marginal improvements in mid-stroke, but can’t fix the excessive end stroke ramp. Overall, relatively minor gain – you’d have to design an air spring specifically for this application in order to make it work well, but fortunately most bikes don’t use this configuration unless they’re intended for use with coil sprung shocks.

3. PROGRESSIVE-TO-LINEAR/DIGRESSIVE leverage rate:
Resultant wheel spring curve with Fox sleeve: high initial leverage helps somewhat to overcome the stiff initial air spring feeling, but unless it’s progressive enough early enough, the mid-stroke is still relatively soft compared to the initial stroke. However, because the leverage rate flattens out (linear rate) or increases again (digressive rate) you do get better mid-stroke support with this, since you can run higher air pressures without causing crazy end-stroke ramp up. However, what we’re really looking for overall, from start to finish, is an increase in wheel spring rate of about 55-65% overall (once shock spring rate curve has been multiplied through the leverage rate curve), which corresponds roughly to a coil-sprung bike with a leverage rate that starts 25-30% higher than it ends (progressive). This is slightly lower than what’s been shown to work very well on both DH bikes and MX bikes, though most air-sprung bikes don’t need quite that level of big-hit performance. In order for this to happen with existing Fox sleeves, we’d need to see frames with ~3-4x their existing initial progression, but only for the first 20mm or so of travel, before becoming comparatively linear throughout the rest of the stroke. This doesn’t currently exist in anything I’ve seen.
Resultant wheel spring curve with Corset sleeve: much closer to the performance of a coil shock (on a bike that’s well designed for a coil shock, not on the same frame!) because the leverage rate change can effectively cancel the slight falling initial rate of the Corset, the supportive mid-stroke of the leverage curve cuts the actual drop in spring rate at the wheel down to zero (or can even allow for a truly progressive spring rate in quite a controlled manner) without causing the excessive end stroke ramp. Once again, you can tune the end stroke with volume spacers.
Net result: Corset provides distinct improvements in bump absorption, support and liveliness. This combination is in my opinion the highest performance currently available from an air shock and linkage curve, on an only semi-related note.

4. DIGRESSIVE-LINEAR-PROGRESSIVE leverage rates:
Resultant spring curve with Fox sleeve: Low initial leverage (stiff) combined with high initial spring rate (stiff) = very stiff initial stroke. High mid-stroke leverage (soft) combined with low mid-stroke spring rate (soft) = very soft initial stroke. Low end-stroke leverage (stiff) combined with high end-stroke spring rate (stiff) = very stiff end stroke. As a result, you get a very stiff feel at the start of the stroke, like there’s tons of preload on the suspension, followed by an unsupportive mid-stroke that is prone to feeling wallowy, which eventually runs into a fairly abrupt wall of progression at the end of the stroke. Good in that you don’t bottom out easily, bad in that if you run higher air pressures for mid stroke support, the early and late stroke segments are just much too stiff.
Resultant spring curve with Corset: Comparatively low initial spring rate reduces the effects of the low (stiff) initial leverage rate and makes the early stroke much softer feeling. You can now run higher pressures for more mid-stroke support without making the early stroke feel too stiff. End stroke is still somewhat progressive – once again, no air spring system out there can really fix an excessively progressive ending stroke of the leverage rate curve – so achieving full travel can still be difficult.
Net result: much better overall in terms of support and bump compliance, but still the end stroke progression issues may remain – removal of any/all volume spacers in the shock is recommended in most cases.

I hope this has helped clear up how the Corset can work for you. Basically, the summary of all of the above is that the Corset is better in pretty well all scenarios, except the following:
1. Frames that already struggle with steep climbs due to slack seat tube angles and/or short chainstays will be worse at climbing. No ifs or buts, it’s just harder if you have more sag. Frames that have steeper seat tube angles, longer chainstays etc (basically the frames that already climb well) won’t be affected to the same degree… I have plenty of personal experience with this!
2. Frames with excessive ending stroke ramp up already will still have those issues – that wasn’t something that we could really address without requiring pressures of 400+psi for the average rider. That’s not to say that the Corset will be any worse, just that it won’t fix that issue. As a general rule, it’ll still perform better overall, but it’s not perfect.
3. If your damper is improperly tuned for your frame (usually as a result of being switched out aftermarket, the ones that come with the bike are generally reasonable), in need of service/repair, this can’t fix that. That’d be like changing your handlebars and hoping it somehow makes your tyres more grippy.

Is it the magic pill solution to every issue with every frame? Unfortunately nope. We’ve legitimately done our best to make this as good as it can be, and this is the ceiling of what we found to be possible. I can confidently say that on 99% of bikes it will make your suspension work distinctly better.