ST4S Mods
 

I need to get my Ohlins shock recondition, l have been told l need a lighter weight spring for my 13 stone body fully leather up.

But this got me thinking, can the front forks be improved?

And is it worth fitting a steering damper,as it does seem a bit flighty over the ton :)

I am not bothered about engine mods, l am really after any mods that will improve the handling.

It would be nice to hear from other ST4s owners, their thoughts on the the ST handling, l find it need loads more input than the VFR's l use to owned, but is very rewarding when you get it right :D

Also the Swinging arm bush, l have not check it yet, but should l change it anyway, the bike has done 25,000 miles :confused:

TIA :)

I would very much doubt many people would be good enough to find the limits of an ST4s on a track and certainly on the road. You say it needs more input, have you lowered the rear wheel? This makes a big difference.

But if you have not done that then it should not be flitty at the ton. Mine has been lowered and is rock solid at 100 +. What changes have you made to the suspension settings? Out of the box they are set soft.

Last guy to service my bike said "it handles well" and he is a club racer.

Set up correctly a S would run rings around a VFR

I not saying mine handles badly, yes it does handle better than a VFR, but l have to move around on the bike more than a VFR, to get the best out of it, hard to explain really:confused:

The bike was set up at Snells for my body weight,they told me the spring was to strong for my weight, and adjusted it the best they could.

When you say lower the rear wheel, do you mean shorten the shock/to adjust the ride height????

I assume Snells had to lengthen the spring to make it softer for me :confused:

So could fitting the new Spring for my weight transform the bike:confused:

General rule of thumb with the ST's is to increase the rear ride to the point where the rear tyre just touches the floor when the bike is on the centre stand....... seems to work a treat. Makes turn in easier/sharper.

As with all things suspension, make sure everything is at stock settings to begin with so you know where you're working from. Preload, damping etc.

Now l understand Lowering the rear wheel.

Mine has quite a bit of clearance below the rear wheel.

So this seems to make sense,as mine needs a bit of persuading, to turn in.:rolleyes:

yep. same thing only different ;)
Try that along with suspension settings at stock and go from there.

Snells may have adjusted your preload, which won't alter the length of the shock when on the centre stand, but may affect the static sag.
you adjust the ride height using the aluminium link rod. Its a b@stard to get to the bottom end of this, but is well worth adjusting it. Doing so also affects the sag.

I have no doubt that my ST4S handles every bit as good, if not better than both the 996 and 998 I had, and it is miles better than a VFR in all respects (power, turn in, brakes).

Tyres play a big part too in sensitivity and turn in speed.
Do you ride with panniers or a top box ?
Top box if loaded up really can get a weave on, especially if solo with it fitted. Its because the weight is so far back.

I think I ride my bike quite hard (difficult to compare with others I've not ridden with), and its as stable as anything cornering at anything up to 140, solo or fully loaded and 2 up. Let the rear tyre pressure pressure get a little low and it starts to 'porpoise' in the bends.

Oh, and I'm a lardy 16 stone. ;)
Hope thats of some help.

Cheers,
John.

Thanks for that, guess what l will be doing today ;) :)

But gaining a extra 3 stone might be a little more difficult :)

Re Tyre Pressures, l run 32 F 34 R what does every one else run??

Got the linkage off as the lock nuts would not move, the jaws of the 19 mm spanners are now 20mm:rolleyes:
So l have just giving it to my mate in a local garage, see if he can heat it up or something?
Maybe that is why no one else has adjusted it, as it looks to be as short as it can be.

I'd like to agree with some of the replies to this and add a bit more..

There's no way on earth that an ST should ever be described as "flighty over the ton". The opposite is the case in my experience - they are much more planted than many other machines. These are the last bikes on earth to need a steering damper.
I believe your ride height is wrong and as mentioned can easily be altered, but over playing with the 3 rear suspension settings can make a real dogs' breakfast of it. If not sure, then go back to manufacturers standard settings (printed in the owners manual) and slowly take it up from there.

The non-fango standard hard luggage will set a small weave up over 125 (due to aerodynamics - not weight), but they are only rated up to 80 anyway, so anything over that and it's on your own head.

I also find tyre pressures really critical on an ST & I think you should try harder settings. My minimum is 36 all round and often 38 F and up to 42 R if two up or riding boring motorways for large miles.

I've ridden VFR's and in comparison I nearly fell asleep with the dullness of them.
The ST will turn fairly slowly if only leaning to steer compared with using oppsite lock steering - then all complaints disappear.

Hope this gives you something to think about and play with.

All the best,
Mike Chadwick

My bike is now solo only, as the wife has a bad vertigo balance problem, which is not getting any better, so bike is a no go for her :(

I do have a Ventura rack fitted, and will not need the panniers for solo trips, so these will be up for sale soon :)

I do love my ST just thought the slow turn in was a Ducati trait, just more involving than my VFR's. and also assume Snells had set it up correctly :rolleyes:

It will be interesting once l do get the linkage back and can play with the settings :)

Mike is right, ST's are not at all 'slappy' and I can't imagine needing a steering damper on mine. If the ride height adjuster is on it's shortest setting, that is definitely your problem. Setting the ride height so that the rear wheel just grazes the ground when the bike is on the centre stand is the way to go, I got carried away with mine and set it stupidly high on the basis that 'more is better' but in fact 'more is just too much'. I had the same problem as you with the adjuster rod and it was because the ally and steel had corroded together. I took the rod off, got it all apart and filled up the middle of the tube with Waxoyl, it's been fine ever since. BTW, may be teaching you to suck eggs, but the bottom thread is left handed, so if you're turning it anticlockwise to try and loosen it, you're going the wrong way.

with regard to the panniers, my advice would be to always use them in preference to a top box or tail pack.
The panniers are above the rear wheel spindle, whereas a top box is way out behind this, much higher up, and really can make the bike move around at 3 figure speeds in windy conditions (no more than any other bike with a top box though). The panniers on the other hand have very little effect that I can detect.

I can say from experience that they don't fall off even when doing an indicated 150 and above :D

As for tyre pressures, I always run those given in the manual, which is 38/42. My experience is the handling deteriorates on lower pressures. Obviously different makes of tyre respond in a different way to this.
I posted something recently to ask others what pressures they run, and it seems most run less than this, but just 2psi down on the rear is enough for me to notice it in faster sweeping bends.

by the way, if you cant get the eyelets out the link rod without damaging it don't get too upset, a new one is only about 16 quid.

Cheers,
john.

Jools: yes l was aware of the thread directions ;)

John W: re Panniers the bike does seem OK with them on, but it just seems neater with the tail pack on, which does sit behind me like having a pillion on board :)

Will get on to mate, to get a new linkage, as if he does have to charge me labour, it will be more than £16.00 :eek:

cant the ventura pack be loaded above the pillion seat rather than behind like the top box.

I run mine on std pressures with panniers, top box and wife and no problems. The only mod we have dione from new is change the rear suspension to Ohlins, IMO worth every penny

Yes the Ventura does rest on the pillion seat behind as l said.
The ST4s does have a ohlins fitted as standard.:)

Standard tyre pressures, my manual are in bar, l converted it to PSI at 32 f 34 r, is this what do you run yours?

st4s mods
 

Standard tyre pressures, my manual are in bar, l converted it to PSI at 32 f 34 r, ......QUOTE]

Really? what were the bar figures?
I converted my owners manual bar figures and came out with around 38 & 41 (ST2)

My rear has always bled air slowly (no pun intended) so I need to pump it before every ride (still no pun intended). If I go out with less than 36psi at the back, the handling is quite badly affected.

Mike

same for me, manual is 2.5 bar and 2.9 bar
2.5 X 14.5 = 36.25psi
2.9 x 14.5 = 42.05psi

I run 38 & 42.

re: the tail pack. I guess that makes a difference if you mount it forward.
Besides, a soft bag on a ventura rack is much less mass than a top box, and less affected by cross winds too ;)
Its personal preference I suppose :)

Those Bar pressures you quote in my manual are for: Rider + Passenger+ Luggage it actually says 2.4 front 2.9 rear.

For solo Rider + Luggage it says 2.1 bar F 2.8bar R without checking that's how l got to 32F 34 R

When l was at Snells l did question the tyre pressures, as they had put new tyres on for me, the front must have loss some pressure as it was down to 29 psi the back was 34, as l always run my VFR's at 36 f 42 rear i thought they cocked up, but they said Ducati's run with lower presssures l think they are right, as l feel the front feels skitish with 36 in it :confused: the rear well the Jury is out of that one, as l cannot tell much differance between 34 and 42:confused: unless l have a pillion.

what tyres are you running ?
I've tried most makes of tyre, and always run 42 rear.

I find anything less than 38 in the front is noticeable as I said.
If the rear is lower than around 38 it too is noticeable even when solo with no luggage. Its most noticeable when getting on the power early out of bends, or in long fast bends where there may be a bump. It feels like the rear rim is rolling in the tyre, funnily enough just like a flat tyre would do ;)
The more you crank the bike over the more it feels likethe rear end sliding away.

By the way, that price for the drop link was a couple of years back now, so it would be a good idea to check first thing monday morning before you make a decision.

To be honest, I will happily ride a bike regardless of compression or rebound settings, but bad tyre pressures I really dislike. If they are wrong, it matters little what you do with the other settings as the bike won't go where you point it.

One final thought: the 4S has the adjustable preload knob, how much of this have you got wound out ?
Either measure the spring length with the bike on the stand, or how much of the adjuster ring is protruding.

For solo Rider + Luggage it says 2.1 bar F 2.8bar R without checking that's how l got to 32F 34 R .....(QUOTE)


I'm wondering if the front feels skittish due to the ride height, not the tyre pressure.
By the way, you need to look at your figures again - 2.8 bar equates to 40.611 psi (at sea level just to be pedantic).
Regards,
Mike

Yes l can't wait for my linkage to come back, so l can play with the settings, l assume when l lower the rear wheel this will put more weight on the front wheel, so l will then need to play with the tyre pressures as well :confused:

Will let you know how l get on :)

It doesn't affect the weight, it affects the head angle.

Only just seen this post as I have been away.
Ride height-as stated by Nelly, rear tyre just kissing the ground when on the stand works for me, the bike will tip in much more easily and you won't need so much bar pressure or lean off to make it turn. I always run 34F 36R pressures-but it's a personal thing tyre pressure, some like them harder some softer. No way does an ST need a steering damper, I have had my '4S from May 2001-it was one of the first delivery-and have done 34,000 miles on it, lots of which have been 2 up with full luggage. It has been to the foot of Italy, and the Arctic Circle, been round the Nurburgring, and used for instructing on our trackday-basically a brilliant bike.

John

Update, :( striped the alloy thread trying to get the ends out of the alloy linkage rod, 10 day wait for the part :rolleyes: £30.00 for the alloy rod, the steel ends are Ok, but if l needed them, they would be £120 each end :o

So bikeless for the bank holiday weekend, and the weather looks good :rolleyes:

Hope l am all sorted for Cadwell Park :)

Eh!!! They're only rose joints :o :o

http://www.merlinmotorsport.co.uk/RO...529/index.html

No parts available at the moment:( so put the old strut back on, l use PTF tape as there still just seems enough thread left, but would not be that confident if using it at Cadwell especially if the rear leaves the ground:o
So l hope the new one gets to me before then.
Yes it does speed up the turn in,:) but it felt stiff at the rear end so wound the the preload out 2 clicks,now not too bad, but it pitch's a bit over bumps, so l have email MD Racing to get it set up properly for Cadwell :D

Also need some new tyres, any good deals about ;) looking for BT016's or perelli Corsa 3, or consider something else if there very cheap:)

I know its a personal thing but when i had my st4s to go to WDW2007 on i bought Bridgestones at the fitters recomend.
Never again, they really did not suit the combination of the bike and/or me. Wore out quickly, didn't like the cold in switzerland and generally were not a patch on 208rr's. Yes i know they are not meant to be touring tyres but waaay better then These.

I seriously wish i had not sold the ST either , big mistake.

I don't bother with corsas, diablo stradas will do everything I can throw at the bike, and last longer too.
I always use a BT020/021 on the front though.

Steer clear of Avons, they don't last very well on Ducatis.

My ST4s has the wheel well off the ground when on centre stand and I don't have problems turning in. You just have to apply the quickturning techniques. The instructor at CSS was actually telling me to calm down the quick turns at last CSS.

I have to say that I would not quite know what to move to as everyday bike. I have now clocked 33,000 (catching you up Monty) and it does everything that I can throw at it. City commute, distance commute, ride out and as the 998 is not ready took her on CSS day and was well impressed. Felt everyway like a Ducati and was creaming quite a few race bikes through the day. The instructor even said at the end of the day that I was doing very well with a bike like "that". Told him that he would be surprised how good it was.

Re mods-
- I fitted a Odyssey battery. Great one and no issue with cranking the engine no more... but need to hack the battery tray and need to reposition the ECU.
- You want to put some silicone in loom going to ECU as water runs down the sleeves and rots the cable at the bottom.
- I have put some 4 pads calipers at the front. Great but need to be regularly cleaned up.
- I ran some 6 piston PFMs for a while. Awesome brakes IMO, I rate them as good as the Brembo GP stuff that I have on the track bike but too harsh for the road.
- I have tried to put 999 master cyls - forget about it. After much swearing in multiple languages I gave up. The lines bolt underneath and that conflicts with the switch gear and throttle. Trying to pivot those slightly is a mess, controls are out of place and still you have to force things in. Pivotting throttle cable 180 degres also means it becomes too short. So you'll have to fit entirely different switch gears and throttle if you wanted to go that way and the stuff from other bikes is not a straight replacement.
I'll probably fit some Pazzo racing levers, that will do.
- I will invest some day in repainting all the cases and various covers as they took some beating from the elements
- I am thinking about Samco hoses as the OEM ones are looking bad
- I am thinking about 996 Rad (ally) as the standard is looking bad, but fittings are different
- I am also wondering if 999 wheels would fit and would look good? Anybody knows?
- Thinking of ohlins forks or changing the bottoms on the Showas as they are pitted. Nice billet radials exist but then would mean changing the calipers
- Thinking about a weight loss exercise, notably on fairing panels. Thinking of trying to make nice carbon ones myself and converting the stupid fairing rubber mounts to quick release. I have not found the time to work on this yet.
- Somebody Ducman I think does some nice billet rear sets. Tempting but quite like the comfort of the standard ones.
- I will invest in some better chain adjustment indicators from Desmotime some day
- I have changed the front speedle for a billet one from Cepeedee (ebay) nice stuff but ally bolt slightly too big. I would love to find a billet rear wheel spindle too as the current one looks well rusty.

I won't play with the engine on this bike. It is more than enough for what I do with her and fingers crossed, it has not eaten any rockers so far.

Cheers
p

Seems like Ducati stopped making a real gem of a bike when they stopped producing the STS. I was very pleasantly surprised on my first track day and for everyday use it is so much fun (except for the bloody heat!). Tire pressures are something I always check before riding and they do make a difference.

I didn't know you had a '4s as well Phillippe-how many bikes is that now??
Yes you are catching me up, but only because I haven't been able to ride mine for the last 18 months-the drop and shoulder injury last year and hand surgery this year has sort of slowed me down a bit. In fact I am selling the ST4S as the riding position is too wristy (believe it or not) for my wrist's now-Sparky is going as well for the same reason.
I have ordered the new Multistrada thingy with the 1198 engine to replace them so all is not lost.............:devil:

John

My ST4s came with some small risers that I removed as I felt the handle bar was too high. Let me know if they would be any help to you. But I guess the new multithingy will be more than enough :D (not sure about knobly tyres though)

I tend to say that I am on 2.5 bikes at the moment.

ST4s for everyday (now heading towards the 35,000m...). I think that when I reach about 50,000 I will do a complete refurb.

+ 1038 RS for the track (998s which just got bored out to 1038cc with RS chassis and big mods. That used to be the bike the Mike Fernandez was racing in MRO. Only thing needed to be finished on her is redoing the race loom + installing a logger.

+ a special built from a 996 SPS Foggy, 996SPS engine with much Corse specs and pretty much full RS/Corse Chassis from a mix of 955Corse / 916R and 996RS. Some compromises made for road usage and will aim to have it on daytime MOT. Bike is currently at Nelly. Should have her finished by Autumn / end of year.

... then the part bin has been growing and I am thinking about doing a Sparky as well on a 996 chassis and Multistrada engine. But that's at least a year away!

You're keeping busy then.................

You really don't need to build a Sparky replica when the original is available you know. :devil:

John

I know and maybe I will think about it next year. But a Sparky is a bit of a personal creation + part of the motivation is to clear the part bin (that includes things like 46mm race ohlins, Brembo GP brake calipers, carbon tank, etc)...

That said if you ever committed the sacriledge to break Sparkie appart I would be very interested in Engine / Loom / ECU / Injection / Dash / possibly exhaust.

p