Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > Sport Touring: ST4 / ST3 / ST2 > ST suspension set up

[YMFB]

I have just returned from the IOM, to accomodate the necessary camping gear we were fully loaded, both panniers, a tank bag on top of the rear parcel shelf and a small tank bag. I accept that at 115 kgs Im not exactly a lightweight by wife is fairly petite. Before we left i wound the pre load right up and generally the handling was OK but we only had to hit a minuscule bump in the road for the old gal to bottom out. Is there anything else i could do, change the spring, fit a spacer, sell the wife. I know that somewhere in this great knowledge base someone else must have experienced satelite spotting at night.

[Rushjob]

Fit an Ohlins as fitted to the ST4S...
Today, mine hashad the joy of myself at 100kgs, and the delightful Yeti, at another 95 or so on it...

Full preload & full compression damping I accept were in use, but it was spot on as we trundled down the A444 at a not too excessive rate of knots.
Mind you, the excellent suspension didn't stop the abominable one falling flat on his derriere outside his house when he got off the bike!!!
I didn't laugh...much

[YMFB]

Rushjob, is yours an ST4, did you fit the Ohlins yourself was it easy enough for a home mechanic.

Thanks for the info

[Rushjob]

No it's an ST4S... Ohlins rear as standard.
If you do get your hands on one they are a doddle to fit. and they will go straight onto an ST2 3 or 4

[YMFB]

does the Ohlins have a wider or higher range of pre-load ?

[Rushjob]

The preload depends on the spring fitted, but as a rule the Ohlins shock is a much higher quality bit of kit and it's adjustment range is far greater than the Sachs / Showa shocks fitted to the other bikes.
It may be that your shock is just tired out & needs a service... how many miles has the bike done?
My Showa on my ST2 bit the dust at about 14K miles ( in the South of France! mind you, it still handled better than the Jap bikes I was with even when the shock was shot! )

[Shazaam!]

You need a stiffer spring.

Two-Up Riding

A number of us ride a biposto (two-seat) Ducati but are unsure about how to adjust the suspension to carry a passenger. So here’s some guidelines using a 996 as an example.

The monoposto (single seat) superbike version is delivered with a stiffer spring than the monoposto to help carry the additional weight of a passenger.



The first step with any new bike is to replace the front fork springs and rear spring (if your weight is less than 155 or more than 165 pounds) and then adjust the preload on the front and rear springs to obtain the correct amount of suspension sag. This should be done preferably before it first leaves the dealership.

Put on your riding gear and weigh yourself. Select the correct rear spring from the following table.




Note that in the above table, that the biposto model springs are always stiffer by two code numbers for a given rider weight.



This mismatch between rider weight and biposto spring rate means that if you’re set-up to carry a passenger, then the suspension will be too stiff for your weight when you ride alone. Notice also that as a compromise, the stiffer biposto spring only partially compensates for 10-20Kg of additional passenger weight. The rest has to be supplied by increasing spring preload before the passenger gets on. More preload (on a softer spring instead of a stiffer spring) will significantly reduce available suspension travel so you’ll bottom-out more readily. There’s really no way to set-up to carry a passenger and still have an acceptable set-up for a single rider. Two bikes is the answer.


[Edited on 6-10-2005 by Shazaam!]

[Gizmo]

the ideal set up is one where you can get 25% of travel as sag (sorry i dont know ST travel) for solo and also loaded. the range of preload means its unlikely one spring will do it. i don't know length of st spring but as Shazaam says you can't just keep increasing preload , there will be a maximum the shock maker recomends. I run 2 springs on my 999, its only 4 bolts to pull a shock out so i swap the spring if i carry a pillion.

talk to a good tuner - K tech are showa importer and ask them which spring they suggest for your solo weight and then 2 up weight. you'll have some adjustment with preload as well. If you go ohlins dont get the hydro preload adjustor as i'm not certain you can swap springs without a compresion stand.

thats for rear only, forks are a tougher one but you have to remember you probably aren't going as quick with a pillion and yor riding style is different. If you want 1 bike to do it all inevitably its a compromised set-up

[YMFB]

Thanks Guys, looks as though I need to spend some money on a new spring or even a complete Ohlins set-up with the external regulating valve. I think I will be off to see Moto-Marelli to see what it will all cost.

[rockhopper]

Remember, increasing the preload doesnt make the suspension harder.