Ducati Monster Forum

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:

(http://www.smugmug.com/photos/i-cq79zCq/0/M/i-cq79zCq-M.jpg)

Which looks like this:

(http://www.smugmug.com/photos/1057111906_zG3SA-M-1.jpg)

(http://www.smugmug.com/photos/1057153518_AgfpJ-S-1.jpg)


And most importantly, I suspect, a revalve from Rick Tannenbaum at Cogent Dynamics (http://www.motocd.com/mc/).

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.  ;D ;D ;D ;D ;D

Great write up.  Thanks  [thumbsup]

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!!!

(http://www.smugmug.com/photos/i-fhzq7WF/0/XL/i-fhzq7WF-XL.jpg)

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.

(http://www.smugmug.com/photos/i-FWQzNk6/0/L/i-FWQzNk6-L.jpg)

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.

(http://www.smugmug.com/photos/i-NMNDpZ7/1/XL/i-NMNDpZ7-XL.jpg)

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  :o ... plenty of goodness to come.  ;D

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

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):

(http://www.smugmug.com/photos/i-bs2JkzS/0/L/i-bs2JkzS-L.png)

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).

(http://www.smugmug.com/photos/i-Mrv28gF/0/L/i-Mrv28gF-L.png)

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.  8)

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.

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...

Yep - it is way better now.  ;D

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.


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.  :-X

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.  :(

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):

(http://www.smugmug.com/photos/i-Mrv28gF/0/L/i-Mrv28gF-L.png)

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.

(https://photos.smugmug.com/photos/i-jtfp3Ff/1/M/i-jtfp3Ff-M.jpg)

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.

(https://photos.smugmug.com/photos/i-rgxTvBX/1/M/i-rgxTvBX-M.jpg)

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.

(https://photos.smugmug.com/photos/i-fTTZ6wz/1/M/i-fTTZ6wz-M.jpg)

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 (http://www.motocd.com/) 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.  ;D

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

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?

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.  ;D

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 (http://teknikmotorsport.com.au/) 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.

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!

Great reports on the process and results.

If you use the bike two-up then the simple fix is just to contact Rick at Cogent and ask him to put my valving in a DU 333 and send it to you. Rick is an Ohlins dealer, and if my experience is any guide he is very reasonably priced. The ability to wind up the preload for two from the hydraulic adjuster, and then back down again for one, is just about worth the price on its own. Doing that one eighth turn at a time with the twin lock-rings is a nightmare, as you probably know. And having the ride-height right with a passenger helps the steering a lot.

The shock will come with a spring, so consider what stiffness you want. I think the OEM 105 spring is nominally too long to accommodate the hydraulic adjuster, but you can get a 105 in the shorter length for the DU 333.  Unfortunately Ohlins does not do a 110 in the right length, so the next step is to the 115.

After fitting the 333, you could sell the OEM Ohlins shock to defray your costs. I have kept mine but should get rid of it - it is just rotting in a box. Had ideas about revalving the OEM and then refitting it before I sold the bike. But I doubt this bike will ever be sold.

Yes, just under 85,000km on my bike now - a bit past 50,000 miles. That is one problem with fixing the shock (and the seat): big trips start to look very exciting.  8)

As noted, old thread still attracting attention and replies ...

Any chance of getting the specific shim set-up you use on your shocks? It would be interesting to compare with what I use on my Öhlins shocks (also softened from the stiff Öhlins set-up).

//Torbjörn.

Hi Torbjörn, no I can't help you with the shim spec Rick used. From our correspondence at the time I remember him saying he had used a small diameter shim quite low in the compression stack between bigger shims, to get that concavity in the profile. As I recall it, anyway - this was a long time ago and no longer very clear in my memory, so I may have that wrong. I never asked Rick to send me the spec.

You could always get in touch with Rick at Cogent, and ask him whether he would share the spec with you. Reference this thread and he will know what you want.

If I were ever to have another go at this, I would probably ask Rick to dyno my spec at about four clicks of compression from full soft, where I use it a fair bit of the time, and then see if he could soften the main valve a wee bit more so that it produced the same profile at 10 clicks or so. That would bring the adjuster back towards the middle of its range for most use.

Fair bit of fooling around for small gains. But I think the step from stage 1 to stage 2 compression damping remains a little bit sharper than optimal when I wind up the adjuster past 10 from full soft. The step to stage 3 seems perfect. (But then maybe what I am feeling is stage 3 cutting in early. I am an enthusiastic amateur here, not an expert.)

Hi Moronic,
sorry for late answer, been down with a mancold.

I actually think I did mail Rick when you first published this thread, but I never got an answer. I did offer to pay, but I suppose he´d play it safe and not let that info out. After all, it´s his eperience, and most people will not open a shock to check so the secret is pretty safe there.
 
Good lead, though, with the small shim between the bigger shims, it does give a clue.

Early December I´ll go to a seminar at Reactive Suspension in York (England) where we´ll see how different shim set-ups affects the dyno curve, and (with Gareth´s experience) what that will do in real life. That will be really interesting.        

Well it's a great thing about this form of communication that slow replies are okay.  :)

I'm just back from a trip away on the Monster, covering about 1350 miles in four days of riding - much of it high-country swervery. Plenty of ice-affected, and frequently patched, bitumen to give the shock a workout.

Once again, the rear suspension in use was even better than I remembered. It is so good to accept that nothing will unsettle the bike. You can attack every corner with confidence, rather than leaving a big margin for the possibility that you'll get thrown out of the seat on entry, or will have to control a weave mid-turn.

Obviously much safer too. You're more relaxed, and can spend your attention (and that margin) on other things.

I would be interested to hear about stuff you learn from the seminar. Either in a fresh thread or, if appropriate, here.

That's why you don't need good suspension if you're not racing, all of that stuff is meaningless while street riding.  :P

Hi Monsterhpd, it would be interseting to hear how you get on. I'm just down the road from York, in Leeds.

I´ll be back with a report.

You could also attend the suspension seminars at Reactive Suspension:

http://www.reactivesuspension.com/courses.php

Gareth Evans is hugely experienced, knowledgeable and pragmatic down-to-earth in his attitude to solve your suspension issues, be they problems or questions. Attending his seminars will be a big aha-experience, give it a try!

   

My forks need a service. Just started to weep on one leg. 15,000 miles and never been done.
I didn't have the oil changed sooner on the advice years ago of a local independant ducati mechanic, as he reckoned that if not leaking, leave them as once disturbed , can be prone to problems?
Sounds like reactive suspension might be the place to go as so near to me. I'd want correct ohlins oil to be used.

Having suspension experts local to you is a beautiful thing. If a tyre change is coming up then put the bike on stands, get the tyre/s changed and whip off the forks for a service. Good solid stands give you peace of mind. Or you can grab the wheel while they are working on your suspension if the tyre joint can do it while you wait.

istamonster, just a heads-up: consider asking the shop to replace the bushes/bearings on which the fork slides.

After my S4Rs Ohlins seals began weeping (can't remember what mileage, but not as late as one might hope), I had the seals done, after which I had serial problems with further leaks. Seals seemed to last about six months.

When one leg went yet again, I asked specifically that the bushes be replaced on that leg with the seals. No problem since, over about four years and more than 20,000 miles.

Coincidence? Maybe. No problem since with the other leg either. Not sure why. It is possible that the bushes had been done on that leg without my asking, during a previous seal replacement - the shop did say it customarily examined the bushes when replacing seals.

I had been alerted by a report online of a similar experience with an OEM Ohlins fork: serial leaks until bushes replaced.


Heh heh, bullseye.  ;D

Cheers for the info/ suggestion moronic, I'll definitely clarify that when i have them serviced.
Koko64, I've got one of these to support the bike
( made in the city where i live, www.1jac.com )
(http://i63.tinypic.com/lzam9.jpg)

Well,
the dyno seminar was very interesting and informative, and unavoidably causing as many questions as I got answers ..... as it should be.

I brought my Monster 800 and 749 / HYM1100 track bike Öhlins and ran them both quite a lot on the dyno (as noted in one of the other Öhlins shock threads on the forum). For comparison, here´s a graph with both shocks with comp 10 clicks out, rebound 12 clicks out, all in imperial units for comparison:

(https://farm5.staticflickr.com/4608/28299105349_73e604e5f4_b.jpg) (https://flic.kr/p/K7Gj6t)Skärmklipp 2018-02-04 16.01.36 (https://flic.kr/p/K7Gj6t) by torbjörn bergström (https://www.flickr.com/photos/125016045@N02/), on Flickr

On the track bike shock, I have since reduced clamp shim diameter 1 mm on both as an experiment, unfortunately I will not have the opportunity to runthis set-up on the dyno so it will be seat-of-the-pants when the track season starts again.

The M800 is pretty much OK as it is.  

BTW,
I think Gareth at Reactive Suspension will offer a dyno seminar sometime during spring. Keep an eye on his home page if you´re interested (and, presumably, not located too far away).       

Hi MonsterHPD, thanks for the nice chart. Could you comment for us on what it demonstrates?

Hi,
Sure. I just put them there as a comparison to the charts on your stock and modified shocks. The format is slightly different, but the units and system of the graphs are the same.
The blue curve is the shock for my M800 and is OK for road riding and track riding (at the pace I´m capable of and willing to risk on it).
The red curve is the track bike, which I have softened up now by reducing both clamp shims by 1 mm. Only riding it will tell how that came out.     

Okay I get it - thanks. Interesting.

So it looks to me like your blue-curve Monster shock is a lot softer on compression than mine at similar settings. But about the same on rebound. Sounds comfy.

What compression setting do you tend to run at? I spend a lot of time within a few clicks of my minimum compression setting. Looking at your Monster curve, that makes sense.

Do you ever wish for more compression damping?

One other thing i notice is that yours is much more linear at the low-speed end - my curve has that sharp ramp up to 1.0 in-sec and then it settles down.

Whereas your Hyper shock is much firmer than mine in both dimensions.


Do you know how the linkage affects things? Are the M800, Hyper and S*R linkages relevantly similar?

M800 and S4R are the same rockers and pushrod, frame pivot points are the same.

AFAIK the swingarm pivot points are in the same spot.

HYM and MTS are most low/forward on rocker pivot.

They may have a different swingarm pivot location too.

Well,
 I ride the M800 mostly alone and on smaller roads where speeds are not so high, but the road can be quite bad. In fact, about 10km of my regular ride is what I use as my suspension test road. No matter what the people responsible try to do to it, it´s always BAD.
So I go for comfort front and rear. Even quite soft, a well-set-up Öhlin (as I´m sure any other quality damper) feels quite OK.  I don´t exactly remember where I have the adjusters, but something like in the graph. (12 to 14 clicks for both). For track riding, I usually firm things up: Reduce sag, more damping comp and reb, maybe around 10 clicks out). I always try to find the right setting from the soft side since too soft is always pretty obvious, too stiff can feel just fine if the track surface is reasonably smooth. It takes a couple of stints to find what seems to work, and as the day progresses, some further stiffening up may be necessary.
Sometimes my buddy (90+kg) borrows the Monster to drive some lady around the track. In effect, that doubles the load and actually works much better than you´d expect, even without further adjustments. Much to my surprise, really …

My track bike is a 749R frame and as such has the linear linkage and the corresponding shock. Due to the shaft bore in the HYM1100 crankcases, the pivot is raised slightly.
 The 3 Ducatis I know reasonably well have significantly different set-ups:

Monster / ST: progressive linkage (around 40% total), shock length 305 mm, stroke 66 mm, spring 100 N/mm. Mine was a DU0462  (old 900-2002) or DU5034 (M800, originally OE for the S4RS). Same shock fits the ST´s, same linkage etc (DU0150, the shock I once had came with a 95 N/m spring).

749/999: Progressive linkage (even the R´s etc), the rocker looks very much the same as the Monster / ST rockers .  I don´t have the spec sheet for 999 shock, but it has a stroke of something  like 75 mm, and came with very soft springs (64 N/mm on many bikes, I have a bunch of them lying around by now …). I think the Biposto came with a 90N/mm spring. I don´t  know how progressive that linkage is, but since the rockers look (or even are) the same as Monster / ST, I expect them to be pretty similar. 

749R: Du to Supersport reg´s, these bikes came with the linear linkage and a shock 305 mm eye-to-eye, stroke 56 mm and a 120 N/mm spring (at least my shock had that). As it came, it was rock hard (at least for me with an empty weight of some 60 kg). I also don´t know how “linear” this is, but the rocker looks definitely different, and it feels very different.  Still not sure if I like it …   
I don´t know if any of this helps, but there it is, anyway. Feel free to inquire further, gla if I can be of any help :-)

Thanks Speeddog, that helps make sense of the divergent curves for the two bikes.

MonsterHPD, thanks for all the info. You are running on your Monster the same rear spring as I am currently. Although I am about 20kg heavier. Still seems to be plenty of spring for me.

Yes, I like your suggestion that the adjustments be set by increasing from soft. As you say, very stiff can feel okay when it's smooth.

My philosophy is to have the spring do as much of the heavy lifting as possible, and add just enough damping to keep it from being bouncy.

Not the best setup for track riding, but that's not what it's for.
Works good for me, and the roads we have around here, YMMV.
And I grew up on long-travel dirt bikes.

My S4 had quite heavy damping that felt really good when the road was smooth.
Small sharp frost-heave bumps in a fast right-hand sweeper convinced me that the OEM settings weren't going to be a keeper.

Speeddog,
that´s about exactly my approach, even if I´ve not put into words like that. It´s important to remember that the damping does not do any lifting at all, it only slows movement.
BTW, the frost-heave experience is the same around here.

One final note on springs: Many years ago I tried an 85 N/mm spring on the Monster. I don´t remember in detail exactly what was wrong, but the spring was definitely too soft; I suppose I could not get the sags reasonable.
Also, with the very progressive nature of the linkage, at least in theory too soft a spring could land you too far into the suspension travel, effectively making the suspension harder du to the progressive linkage (in spite of the spring beeing softer).
Anyway, 95N/mm or 100 N/mm seem to work, can´t really distinguish between those two.   

I am probably with you guys completely on all this but I do want to put up my hand for compression damping, which lets you run a softer spring and can help a great deal to stabilise the bike when you are going for it.

The overdamped stacks that Ohlins has specified for some Ducatis including mine has given it a bad name.

On the rebound side, yes I too prefer just enough rebound control to keep the bike mostly settled. I know mine works because about a year ago I caught a slippery patch on a cold tyre at the exit of a third-gear suburban left-hander and I could feel the rebound operating to resolve the near-highside that followed. It was lovely.

A well tuned compression stack is a great thing. And it works with the soft rebound side. It resists the bike's settling into hollows and onto humps, leaving the spring with less work to do and the rebound with less spring to control.

But yes, it has to be gentle enough to let the wheel move freely over frost heaves. Once the main stack is right, having some adjustment on the fly is a great help as well.

That's the balance, compliance vs. 'platform'.

I consider the soft spring / more damping to be The Official Ohlins Tuning Philosophy.

It's the fore-aft pitching stiffness that's primarily at play.
The bike will get into and out of corners better, as the geometry changes less and/or slower.



I've experimented very little with the rate progression of the rear.
Too expensive and difficult to measure, to start with.

I've experimented quite a bit with the progressive nature of the forks.
Brad's talked about it quite a lot.

The 'too-soft springs with too much rate progression' is basically the OEM fork setting for most Monsters.
They don't bottom out noticeably, they just get so stiff so quick that it stops movement (not so different from bottoming out, for all practical purposes).

If you're relatively light, 150 lbs or less, it's kinda OK, as you don't spend so much travel in rider sag, and you're OK with less spring rate as you're lighter.

The fundamental weakness is that the normal suspension travel is then rather short.
And it gets worse quickly as you get heavier.
Theoretically you can preload it up to get the sag with rider to a good number, but it just moves the un-usable travel from the top of the stroke to the bottom.

Straight rate springs and lower oil level get you into a more usable range of progression.

As a street rider, I find the limitations of less pitch stiffness are more acceptable than the harshness on sharp edges.
I don't fling the bike around, and I try to ride big round corner lines (must look like a very slow version of JLo  [laugh]).

I suppose the damping vs. spring situation is mainly about finding a solution one´s happy with. As is most suspension work, really, I don´t think most members on this forum will ask the stop watch if the suspension change made it better or worse.

One thing to keep in mind, I believe, is the different nature of damping force and spring force: Spring force is linear against movement (installed in a bike shock, non-linear as dictaded by linkage) and not affected by damping speed. Hydraulic damping force is not affected by position (again, modified as dictated by linkage) but proportional to damping speed squared. This "Vsqared" effect is basically what is compensated for by a good shim set-up.

As with springs, I personally prefer going on the soft side with the damping, especially on the street, since my aging body really dislikes the beating frost heaves and such dishes out otherwise.  Fast people on good roads or a track might want a firmer set-up, or just plain like it so.