Updated again: Cogent Dynamics Monster S4Rs Ohlins revalve

[Moronic]

It took more than three years, but finally I have a rear suspension for my S4Rs that works like I hoped it would stock. (Deeper in this thread at reply 10 is a report on this mod after more than five years of use.)

I've gone for this:



Which looks like this:






And most importantly, I suspect, a revalve from Rick Tannenbaum at Cogent Dynamics.

You could duplicate the valving I have without replacing the OEM Ohlins shock. But I wanted the remote preload adjuster, and the remote compression damping adjuster, which is sited under the fuel tank so that you can tweak it easily while riding.

This shock is the DU 333 that Ohlins built for the pre-06 S4R. It bolts straight on to the S4Rs.

Background

The OEM Ohlins shock (officially a DU 5034) always felt way too harsh for me when the going got a bit bumpy. Roads over here are a bit bumpy most of the time, so that was not what I wanted from an Ohlins rear end with nearly six inches of travel.

I'd previously had my OEM Ohlins revalved on the compression side of the main valve, to match the DU 333. The result was an improvement over stock, but still too many sharp kicks in the bum that could not be tuned out with the adjuster.

I'd just about given up in despair, when Rick answered an email I sent him. After extensive correspondence, Rick got it that I knew what I wanted, and I felt confident he knew what I wanted.

Even so, it seemed like a big ask for him to translate my seat-of-the-pants impressions into valving that worked for me.

Nevertheless he did, sending me a shock with about 15 per cent less compression damping in the mid-high speed area, but with the low and very-high ends similar to std Ohlins performance (as tested on his shock dyno).

Results

I can't say enough about the care and attention Rick gave to this work, especially given the paltry fee he charged for it.

The result has transformed the bike. It is difficult to do justice with a description to the improved ride. Suffice it to say that she rides like I'd always imagined a road bike with an Ohlins damped, long-travel rear end should ride. Smoooth, and soaking up just about everything.

I am sure Rick has the modified valving on file. Anyone revalving the OEM Ohlins to this spec should get the same ride, as the main piston, compression adjuster valving and rebound adjuster needle are the same on both shocks.

A few caveats:

1. Make sure you have Rick fit the DU 333 rebound valving as well as modifying the compression valving. After riding on both, I believe the 333 rebound valving is more subtle than that on the OEM 5034.

2. Even though I am running a significantly firmer spring than stock, I needed to back off the rebound adjuster three clicks from the recommended setting (to 17 out from full hard) for good ride when cruising.

3. Even though the compression valving is softer, I needed to back off the compression adjuster five clicks from the recommended setting (again to 17 out from full hard) for good ride when cruising.

4. The compression valving Rick ended up using was quite tricky and complicated, as he altered the shape of the damping curve to match my perceived needs. I suspect that if an S4Rs owner living nearby was able to work with Rick to test other options, you might get an even better result from a simpler spec.

5. The overall result convinces me that there is no inherent problem with the S4Rs suspension link that mandates a harsh ride. Indeed, the top link runs the same part number as on the ST4s sport tourer, which I believe rides quite well, and as the specified travel is the same 148mm, I am guessing the geometry is also the same. If you want your Monster to ride like a sport tourer, the fix can be all in the damping.

6. This linkage feels quite progressive and hence the ride is quite sensitive to spring preload. You want laden sag in the 30-40mm range.

The DU 333 remote adjusters vs stock

So that is the revalve. Now a couple of comments on the remote adjusters.

Simply, they are the icing on the cake.

The remote preload adjuster is helpful not only to adjust for a passenger or touring luggage. It also allows rapid fine-adjustment of sag so that you can dial in the ride you want. Especially handy given the sensitivity of the linkage.

Of course, you can also use it for making fine adjustments to ride-height, and hence steering, at the price of having the ride slightly off.

The remote compression adjuster allows you to test for the optimal setting while riding. Of course, you can also dial up some extra compression damping on the fly if you hit some sweet, smooth twisty stuff and want more control.

All in all, highly recommended.  

[Jarvicious]

Great write up.  Thanks 

[zooom]

I've known Rick for a lot of years and he is in fact a suspension guru....I have refferred many people to him....great guy to chat with and good solid businessman...his website could use some help...but that isn't his forte and never has been...can't reccomend him enough!!!

[Moronic]

About time I updated this to reflect more experience with this mod.

I've spent months chasing and sorting a rad leak, finally replacing the radiator, so hadn't until recently been able to confirm my initial impressions.

Finally got away recently for a round trip of 1200km or so - about 700 miles, solo and loaded for camping.

I've been reluctant to rave hard about just how good the rear end of the S4Rs is with the Cogent Dynamics revalve, mainly because I keep thinking I have overestimated the improvement.

But with this trip, any reticence was blown out the window. The rear end of this thing is brilliant.



I will confess I have been surprised not to see more complaints from other S4Rs owners about the jarring rides they get out of their Swedish rear shock. Used to wonder whether there was some blockage in mine. But after two rebuilds, the stock unit still was appallingly harsh, in the conditions here anyway.

What to say about the ride now? Possibly most saliently, it is where I hoped it would be all along with an Ohlins shock, in that you find a setting that works and forget it.

I gave good rebound and compression settings in my first post. It is telling that I've not bothered counting clicks since. I set the rebound for this latest trip after tweaking it a bit for commutes, and it was perfect for the entire 1200km. Never occurred to me to adjust it. Well ... it did occur to me at one point to add a single click, but I couldn't be bothered - and in hindsight, doubt it would have helped.

The compression? Again, tweaking while commuting may have fine-tuned things a little. I think I may have wound off a single click while touring down a relatively major highway at the speed limit early on, and may have added two clicks from there to return the steering to neutrality on some wet forest roads later in the journey, but that was it. Everything I wanted in a three-click range.

That's the Ohlins I remember. With the stock unit, I was forever fooling around with settings, trying to find something that worked.



What remains is to give you an impression of what the ride feels like now. Best way I can think of to put it is that she now feels as though she rides just on the spring. It is as though you can feel just the spring under you at the rear, nice and firm and supportive, and nothing else. No kicks through the arse from the damping. Of course, if it was really just the spring under you, you'd be bouncing all over the place and the rear tyre would be pattering and bouncing through every corner. So obviously, the damping is doing lots of work. It is just that you don't feel it: the damping is transparent, which is probably the best compliment I can pay it.

I said in my opening post above that if somebody lived close to Rick they might work with him to put together a simpler set-up that was better. I want to resile from that. I have begun to suspect that Rick's tricky valving is way ahead of anything Ohlins has specced stock for a Ducati on this sort of shock (bets off for the TTX models).

Anyway, lots more I could say but if I keep rabbiting on no-one will believe me. Perhaps I can finish with a comment I made to Rick early on in a thank-you email. At the time I thought I'd gone over the top, and would live to be embarrassed by my enthusiasm. But on this recent trip it kept occurring to me that if anything, my initial impression fell short of the mark. So what I said then bears repeating: this valving offers the sort of ride that everybody dreams about, but hardly anybody ever gets.

And the S4Rs? Well, with the suspension sorted, there really is nothing like her.

And I'm still running the stock exhaust   ... plenty of goodness to come.  

[Billyzoom]

I KNEW IT WASN'T JUST ME!

I hate the rear suspension on my S4Rs....I took it in for one of those quick setup clinics to make sure the sag and such were set correctly, played with the damping, and still VERY harsh. 

That may be the answer for me.  Thanks for the great writeup!

Joel

[Moronic]

G'Day Billy,

yes, you do feel like a bit of a klutz when you can't get your top-line suspension to work as you think it should ... 

I'd had previous experience with Ohlins on another bike but of course the linkage is part of the picture and my fear was that the Monster's linkage was the problem. Indeed, I got that suggestion from a couple of experienced people among those from whom I sought advice.

Not so.

No idea why Ducati was happy to spec the damping they supplied stock. I've not found any downside from the revalve: you can dial in as much control as you want; more in fact.

Just in case you missed it: you should be able to get the same result I got just by having Rick revalve the OEM shock for you to the same spec he used for mine. Point him to this thread if he needs reminding of the relevant spec.

Are all other owners happy with their S4Rs rear ends?

Probably a bit technical for most, but I'll post two shock dyno graphs Rick sent me of the modded shock against the stock DU333 aftermarket unit. (No graphs of the stock OEM DU 503 unit, unfortunately: that would have been interesting.)

The first shows the std DU 333 in blue against the modded unit in red, with the clickers on both set to manufacturer recommendations (14 clicks of rebound and 12 of compression):



The left side of the curve is low-speed, the right side high speed. The upper curves are the compression curves (lowers are rebound). You can see that the red curve for the modded shock is slightly concave, showing a reduction in damping force concentrated in the mid-high speed part of the spectrum.

Now take a look at this next chart, which shows the std DU 333 in blue with the compression adjuster set to minimum (i.e. 23 clicks out), against the modded shock in red still with the compression adjuster on std (12 out).



Rick observed of this chart: "The curves are very close but with more low and high speed compression yet a little less mid-speed."

You can see that the change is fairly subtle, but basically the mods have brought the compression adjuster into play - 12 clicks on the modded unit roughly matches full soft on the original, which was still too hard - while softening the mid-high speed area a bit but retaining plenty of protection at the high end against hitting big holes or sharp steps.

Of course, the actual settings I have found best in use are not shown on the charts. But as I tend to run the compression adjuster about five clicks softer than the Ohlins std spec, this will be five clicks softer than the softest setting available from the DU 333 as Ohlins supplies it - but with the effect felt more in the mid-high speed part of the curve than the low and very high ends.

As the OEM shock was valved even firmer on the compression side than the DU 333, you can imagine the change over stock.

The improvement in riding pleasure cannot be overstated. The reduction in rider fatigue is dramatic, and of course control is much better also, as the rider is not being thrown around and the tyre tracks the surface more accurately. 

[Christian]

Very interesting stuff!

My S4RS does indeed feel harsh, but I just assumed that was because it was setup to be more "sporty".

Question for you - does the revalve change the dynamics of the bike from a sport perspective? I mostly tool around town in my S4RS and have a touring bike for the long trips. I'd love to take the Monster out on some longer treks now and then but I don't want to sacrifice the flickability and sportiness in the suspension right now. Despite being harsh on bumpy east coast roads, I do enjoy riding it very much - especially in the twisties.

[mattyvas]

Excellent details, I have always had the same feeling of the rear and front for that matter on my bike.
Though coming from a 620 which had Ducatis cheapest suspension in the market it is certainly an upgrade.
But you are totally right, it is overly harsh on all roads. I don't load it all that much myself only putting about 62kg or so on it when I'm on board. Still it is very "solid" when it comes to dealing with road surfaces.
I did have some simple setup work done by a suspension place here in Sydney but that didn't include any rebuilding it was just setup and tuning.
Perhaps I might need to pay some more serious attention to it.

Thanks for the great info and detail.

Matty...

[Moronic]

Very interesting stuff!

My S4RS does indeed feel harsh, but I just assumed that was because it was setup to be more "sporty".

Question for you - does the revalve change the dynamics of the bike from a sport perspective?

Yep - it is way better now.  

You can feel that little bit of concavity in the compresson curve - the rear will compress (sag) a little more when you hit stuff - but there is still plenty of support. When the set-up is nice - round about the settings I gave in the first post - you can still feel every ripple in the road but they don't intrude. You get a seat-of-the-pants awareness of the condition of the road surface, but you don't get kicked in the pants ...

Remember too that, as the curves show, the revalve gives you proportionally more low-speed control - which essentially is control over chassis attitude. In other words, for a given setting of the compression adjuster, the proportion of low-speed resistance to mid-high speed resistance will be greater after the revalve. Or to put it yet another way, with the modded unit, you don't need to sacrifice as much low-speed control to get mid-high speed compliance.

I can't remember quite where I saw this, but it was in a fair-quality Euro or Brit bike mag that quoted the suspension settings they found best when testing, and I was a bit shocked to see they had featured the S4Rs in a comparo and had recommended the compression adjuster be set at minimum. And that is basically what I found with the stock shock. You set the compression at minimum because you wanted to minimise that mid-high speed harshness. But even minimum didn't do that. So effectively, on the stocker, you had no compression adjustment: minimum was too hard, and you couldn't go any softer.

After the revalve, you can use the adjuster. So if you want more compression firmness on very smooth twistys, just wind it up. Obviously, you won't quite get the feel of the stock shock: that little bit of concavity will remain in the curve. For me, that's a good thing.

I should add tho, that I am not claiming the valving I have could not be improved on, even for me. I know Rick wouldn't make that claim either. With more iterations of pull-the-shock, revalve, ride and repeat, doubtless it could be brought even nearer perfection.

However, it is bloody good, and extremely satisfying to ride on. The point of my posting about it, is that I feel I can recommend it with a lot of confidence. It is, if you like, a plug-and-play major improvement, rather than a shot in the dark. At the very least, fitting it will give a sense of just how good that Monster linkage can be over rough stuff (brilliant!). Afterwards, if you found you wanted to go back some way towards the stock feel, you could ask for that. Me? It will be a long, long time before I bother getting this shock pulled apart again.

Excellent details, I have always had the same feeling of the rear and front for that matter on my bike.

I have always liked the feel at the front. On mine, very compliant, but again you can feel what is going on at the road surface. If you are using std settings, have a std spring and the fork fluid is std Ohlins stuff, you should be good.

However, I did see a post recently on multistrada.net where an owner pulled down his harsh-feeling OEM Ohlins fork and found some stray material blocking the valving on one side.  

Thanks all for the appreciative comments. I was beginning to wonder whether everybody but Billyzoom (apologies Joel for referring to you above as Billy) had found the topic too hot to handle.  

[Speeddog]

Very much in line with how I feel about the aftermarket 46PRCS Ohlins I've got on my S4.

I'm at the minimum on the compression adjuster, and it's still harsh.
Unfortunately, as you've noted, trying to fix a mid-high speed damping issue with the low-speed adjuster isn't effective. 

[Moronic]

Since this thread is still attracting reads, I thought it worth updating to reflect some more extensive experience with this valving on the Ohlins DU 333 shock.

And in particular, to correct a slightly misleading answer I gave to Christian's question above (five years ago!) on the suitability of the valving for riding quickly on good roads.

I am still riding - and loving - my S4Rs. But I have moved from Perth, on the west coast of Australia, where there are few of the mountain and coastal type roads where the Monster is at its best, to Melbourne, in the state of Victoria on the east coast, where mountain and coastal roads abound.

I am also using the bike almost exclusively for solo rides now - again its more natural environment - and so have softened the rear springing, going to the 100N/mm spring that comes standard on the DU 333 (and which is slightly softer than the 105 that is stock on an S4Rs).

The combined changes to the riding environment and the springing has meant I have had occasion to wind up the compression damping past the soft end of the scale where I was using it in the less inviting conditions of WA.

In so doing, I have discovered something that should have been obvious from one of the dyno charts I posted above comparing the stock and modified valving. Here is the chart (look at my post above for how to read the curves):



It shows the modded unit (red curve) at 12 clicks of compression against the stock unit at zero. And as Rick observed of the chart, the two curves are very close (top curves are compression).

Well, that closeness was just what I experienced on the road, when I had occasion to wind on about 12 clicks of compression while tackling some mountain swervery.

At that setting, the rear was as firm on compression as I could possibly want in such going. And once again I could feel the relatively sharp ramping up of the compression at mid-speed that I had experienced when using the stock DU 333 valving that I had applied at one point to the OEM DU 503 shock.

Again as expected from the curve, the sharp compression ramp was attenuated slightly by Rick's valving. But only slightly - and the attenuation was absolutely a good thing.

So that is the answer for Christian and anybody else interested. Rick's modification allows a near identical setting to the DU 333 if you want it. I do not doubt that at compression settings of more than 12 the modded shock would continue to emulate the unmodified DU 333 as you wound it up from zero.

The fact that I had no need of more than 12 (or so) clicks even in these conditions on the modded shock also helped confirm that the DU 333 in stock form is overdamped on compression for most road riding.



I believe I have put more than 30,000 miles now on the modded shock (yes, I have also had it serviced a couple of times). The ride it offers continues to delight me in all conditions, and while the bike now can take advantage of all its magnificent 148mm wheel travel, never once has the shock bottomed out harshly. The high-speed damping always catches the biggest hits before maximum travel is reached.

Meanwhile, I have also taken an opportunity to re-sample the OEM DU 503 as it came stock on a riding companion's S4Rs. I had wondered whether I would discover it was not as bad as I had remembered, or that my own OEM unit had been uniquely faulty. Oh no. That same floating around in the low-speed range with a dramatic shift to an overdamped mid-speed was still there, exactly as I had recalled it from my time with the unmodified OEM rear.

I also reported above on the advantages of having the remote compression and preload adjusters that come with the DU 333. Nothing has changed there, except that my appreciation for their benefits has grown.



The ability to experiment with compression settings without stopping the bike contributes enormously to my ability to find precisely the setting I want in any conditions. The only thing I wish is that I had looked for a way to mount the remote on the left side, so that I could adjust it without releasing the throttle. Perhaps one day - although it seems likely Ohlins would have done it that way if it had been easy to do so.

BTW, for those who have not used accurately valved Ohlins shocks: two clicks of compression makes a significant difference to the way the bike rides. Four makes a big difference. Twelve makes a huge difference.

The sensitivity of that Monster chassis to rear ride-height also means the remote preload adjuster can affect to a remarkable degree how the bike steers.

I have extended the rear ride-height rod by I think about 4mm over the stock zero setting, coming back slightly from my original guess at (again IIRC) 5mm. That equates to a taller ride at the rear frame of about 10mm. By manipulating the hydraulic preload adjuster on the shock, I can tune the steering from there between a slightly lazy setting where she wants to run a little wide, to an overly agressive setting where she falls in quickly but is a little unsettled mid-turn.

Both extremes are useful under certain conditions. And in between, you can set her for very low-effort turn-in but superb mid-turn stability.

And all this can be done while leaving sag in a good place for riding the bumps. As little as half a turn on the preload adjuster handle makes a difference to the steering that you can feel quite easily.

As well as tuning for different road conditions, the preload adjuster allows you to tune the steering to compensate for rear tyre wear: as the profile comes off the tyre, you can add a bit of ride height to preserve much of what you want for both fall-in and mid-turn.

The hydraulic adjuster is in an awkward place below the seat on the left side. But with some experience you can find it easily while riding, and hoik the bike up or down with a few rolls of the hand.



As valuable as it is to be able to tune compression and preload for the conditions while riding - or for carrying a bit of luggage - a related benefit also presents itself.

The performance of the chassis becomes a fluid thing, rather than a mechanical rigidity that you compensate for in your riding. You can at any time make the bike feel a little steadier or a little sharper, a little looser or a little more solid. To put it another way, you can adjust the bike's character to match your mood - adding some verve if you are bored, or subtracting some if you are tired or just want to relax. This of course is what electronically controlled suspension modes on more recent bikes promise, but I have put miles on a couple of such bikes and the effects of the changes have not felt nearly as enlivening as they do on the Monster.

Finally, a note on the OEM Ohlins front fork. Having experimented inadvertently with alternative fork fluids, I believe the Ohlins-brand fluid is the only one worth considering. I have tried alternative springing, and have settled for a stock spring on one side and a slightly stiffer 9 N/mm spring on the other. (I weigh about 76kg - 170 libs - without gear.) The single 9 has been enough to preserve some bump travel under fairly heavy braking while retaining so much compliance that most of the time road imperfections come through to the 'bars as gentle taps without seeming to raise or lower the bike itself at all. The handlebars feel - peculiarly - rock solid in a vertical plane, responding just to your steering. I have never needed nor wished for a steering damper.

Well, that turned out a lot lengthier than I had planned - I hope the info is useful for someone. Much of it of course would also be applicable to the 996 or 998 engined S4R, and to the S2R, all of which use a chassis that is almost identical and that accepts the DU 333 shock.

I was in touch with Rick at Cogent Dynamics only about 15 months ago and he remained well aware of the valving spec he had supplied me - and of course was delighted it had continued to give such good service. He also said a few people had asked him to replicate the spec for their bikes, alerted to its benefits by this thread. I hope those trusting souls have enjoyed the revised ride as much as I have.  

[Christian]

Thanks for the update! Always nice to get some feedback from many miles on the bike.

[itsamonster]

I would love to get my rear shock done. Shame your suspension guru is on the opposite side of our planet from me! Doh
Have you ridden it with new shock specs and original spring?

[Moronic]

Christian, glad you're still following the board. It was fun to see your reply, so soon after such a long period since my previous response.  

itsamonster, I have not run this shock with the OEM 105 spring rate but I have run it with 120 and 115 springs as well as the 100. In WA my Monster was ridden a lot two-up (we had a custom saddle made), hence my need then for the stiffer spring. This valving was superb with two reasonably light people on board and the 115 spring. (The damping was also good solo with the heavy springs, but obviously the bike was oversprung for just me.)

Given that the modded shock works very well at either end of that spring spectrum, it will also be superb solo with a 105 spring, if you just want to revalve the OEM S4Rs shock.

I see from your profile that you are in the UK. There is bound to be a suspension shop there that can soften the compression damping for you (and replace the rebound stack with the 333 stack, if you want that too). It seems fairly widely known that Ohlins specs its compression stacks on the firm side for some bikes - and particularly, perhaps, for Ducatis. It is just a matter of looking or asking around until you find a shop you feel you can work with.

In Australia, I had a conversation with a staffer at Teknik Motorsport in Sydney, and he seemed very familiar with the prospect of softening the compression stack on an Ohlins equipped Ducati. Said the shop had done that for several bikes, and had good valving specs on file.

The main reason I went with Rick at Cogent instead was that by the time I found Teknik I was well into negotiations with Rick, whom I had sought out because he had posted helpfully on some Ducati forums.

Because most riders don't know much about suspension, it is easy for suspension techs to assume they know more about their customers' needs and wishes than the customer knows. Possibly that's often right. With Rick I felt I had found someone who was interested in my description of my problem, and willing to trust that I would appreciate his efforts to solve the problem as I represented it to him. As well, I was corresponding directly with the person who would do the work, and not with an intermediary.

Neverthess I believe suspension valving remains as much art as science. Likely we were a bit lucky that the outcome in my case was so successful. And that is a big part of why I have wanted to share the result.

[itsamonster]

Thanks for the reply. It's deffinately something i need to get done.
I've had the bike 8 years and mostly ride 2 up. I get the jiggling on fast country side roads.
Your putting some serious miles on yours!