race settings suspension 750

discussions specific to the 750 Paso

Moderators: paso750, jcslocum

Post Reply
User avatar
Brutus
Posts: 257
Joined: Sun Jan 16, 2005 12:00 am
model: 750 Paso
year: 1989
Location: The Netherlands

race settings suspension 750

Post by Brutus »

Hi guys, anyone knows the suspensionsettings to achieve a more racy-character..? I'd like to know the front setting (current=2), rear setting (current top of shock=4, downside of shock=2)

grz Léon
_________________
Better too late than too ugly..
Duc750
Posts: 373
Joined: Mon Apr 03, 2006 12:00 am
model: 907 I.E.
year: 1993
Location: Northampton UK

Post by Duc750 »

"racy suspension settings" don't exist. What are you trying to do ?

for example speed up turn in ?


The basic place to start before changing any settings from stock is to set the static sag front and rear.

Once you 've done that the best bit of advice I've ever had is to go out and ride - learn to ride the bike and then start playing with it!

To that end I'm still learning.! :laugh: Perhaps if I get my Rospa instructor this year I might adjust my compression damping but it'll be another 100K miles before I touch the rebound :laugh: :laugh: :laugh:
User avatar
Brutus
Posts: 257
Joined: Sun Jan 16, 2005 12:00 am
model: 750 Paso
year: 1989
Location: The Netherlands

Post by Brutus »

I would like to know if people have any experience in adjusting the suspension settings that gives me the best handling on the track. If anyone has experience with this setting, plz let me know.

regards, Léon
_________________
Better too late than too ugly..
Duc750
Posts: 373
Joined: Mon Apr 03, 2006 12:00 am
model: 907 I.E.
year: 1993
Location: Northampton UK

Post by Duc750 »

OK well my settings would be totally different to you but as a starter.
Set your rear axle adjuster to the lowest position (so you get the most rear ride height.)

Then set your static sag up correclty. Its amazing the difference it makes. There are some good articles on the web with step by step guides on how to do it.

Everying elese is personal but be aware that you can turn a bike that handles ok into a real dog very quickly.
Make changes to one thing at a time and then ride it.

I still stand by what I've said above
User avatar
jcslocum
paso grand pooh-bah
Posts: 1714
Joined: Mon Jul 19, 2004 12:00 am
model: 750 Paso
year: 1988
Location: Eastern Shore, MD
Contact:

Post by jcslocum »

The Paso will never really be "racy" but with the set up written above it will steer quicker. I have also found my Paso to be very sensative to tire pressures so make sure to play with this as well as the suspension.

You MUST keep a log of your starting point and any changes that you make. This will allow you to go back to a good setting and help you understand what each change does to the set up.
User avatar
ducinthebay
paso grand pooh-bah
Posts: 1323
Joined: Sat Sep 03, 2005 12:00 am
model: 750 Sport
year: 1990
Location: SF Bay Area

Suspension setup

Post by ducinthebay »

Start with getting everything else correct on your bike. Grease your headset and adjust it. Get new tires if yours are worn. Check your tire pressures. Change the fork oil, and make sure your forks are not binding. Clean and lube the shock joints in back. Make sure everything is tight and right.

Suspension tuning is a bit like carb tuning, it benefits from expertise and experience. I have found that buying that expertise is well worth while. After having my forks on my ST2 rebuilt by Aftershocks, I had Phil, the owner, set up the suspension for me and my riding style. He started with the right spring rates, then the sag on front and back, then adjusted the compression and rebound damping. It truly made a world of difference. I haven't changed it since.

Like carb tuning, only make one change at a time, so you know what you have and can feel the difference. Like John says, keep good notes. Find a short route that has a variety of road conditions and test out the changes, one at a time.

If you have a local suspension shop, go there. They do this all day and know quite a bit. Your bike will definitely ride better after you leave. Some of the Ducati gatherings, or track days, or other motorycle meets will have a tent from the local suspension shop. For $30-50 they will adjust your bike as far as they can, and make recomendations for what you should do next. Trust me, its money well spent.

Hyperpro makes springs for our bikes, but it's best that you get a professional opinion before you go and buy new parts that you may not need.

Suspension is never perfect, but better is, well, better.
Duc in the Bay
1990 750 Sport x2-Rosso Blanko (900ss copy) & Nuovo Nudo (Scrambler project)
1991 907 -mostly stock
2002 ST4s - Lots of mods.
User avatar
Harigeharry
Posts: 87
Joined: Tue Apr 04, 2006 12:00 am
model: 750 Paso
year: 1990
Location: Amsterdam

Post by Harigeharry »

I have a basic document from Ohlins.

And a document special for Ducati's from Affetto (Netherlands).
I am willing to translate it if there is need for it.

First the Ohlins story:
Introduction
Unfortunately there is no literature that can give you the perfect machine setup. Also suspension setup is individually dependent on the rider (style, preference) and track conditions, which vary from race to race. We can therefore only try to give you guidelines and ground rules for the chassis setup of your machine.

General guideline
The general guideline in road racing is that the suspension has to support the tyres to create the best possible grip. For this reason suspension plays it's most important role in corners, chicanes, acceleration and braking. In the straight line the suspension works satisfactory if it can absorb the bumps without causing instability.

Suspension stroke
A road race bike should normally not use its full suspension stroke, although on some circuit one or two big bumps or hollows can cause the suspension to bottom. Also landing of front wheel after wheelies can cause excessive use of the front fork stroke. If suspension bottoms in big bump or hollow, it should not automatically mean that the suspension should be set more hard. However, if suspension bottoms at the place were the maximum grip is essential the tyre cannot create the best traction, because it also has to perform as spring. Adjusting the setting is necessary. During every riding session the suspension stroke should be carefully checked.When tyre grip and lap times improve, the suspension has a harder job. So, setting must be set harder. On the opposite, when it starts raining tyre grip and lap times go down, in that case a softer setting should be applied.

Suspension setup
Before starting suspension setup, read the owners manual!
A tip, do your changes in suspension setup one by one, try to learn what effect each individual adjustment has on your bike and take notes!

Static sag without rider
Hold the bike upright on a flat surface. Independently lift front and rear until the suspension is fully extended, the value should be approximately:

Type Front sag Rear sag
Super Bike 20-30 mm 5-10 mm
Super Sport 20-30 mm 5-10 mm
RR 250 15-25 mm 0-5 mm
RR125 15-25 mm Just top out 0 mm

Note: An RR 125 cannot afford to loose the momentum that the sag would give in a straight line (loss of top speed). The static sag is adjusted by the spring preload. The procedure is the same for the front fork and rear shock.

Static sag with rider
The accepted manner to adjust the spring ratio is to measure how much stroke is used with the rider sitting on the bike in straight line position (behind fairing) after you have set the correct static sag without rider. Normally 1/3 of the full stroke is a good starting point for all machines. This is only a guide line for the right spring ratio. The final check must be done on the circuit.
Note: Ohlins racing shocks features a "top-out" spring to prevent the shock from extending to quickly, causing the rear wheel to jump under braking. The top-out spring also effects the negative sag, making it difficult to adjust the sag with the shock on the bike.
Your Ohlins shock is delivered with the correct spring preload set and we recommend you to use this value for the basic setup. Ride height should be adjusted with the ride height adjuster on the bike or on the shock.

Rebound damping

Rear suspension
Too much rebound damping can cause:
The rear "jumps" on the bumps instead of following the surface.
The rear "jutters" under braking.
It holds the rear down with the result that the bike will understeer!
It can cause overheating in the hydraulic system of the shock absorber and make it fade, in other words, it will loose damping when hot.
Too little rebound damping can cause:

The rear "tops out" too fast under braking, causing the rear wheel to jump
The bike feels unstable.
Front suspension
Too much rebound damping can cause:

Oversteering!
It will give poor grip of the front tyre.
It feels like the front wheels will tuck under in corners.
Too little rebound damping can cause:

Understeer!
The front can feel unstable.

Compression damping

Rear suspension
Too much compression damping can cause:
The rear wheel to slide under acceleration.
It can give a harsh ride over bumps.
Too little compression damping can cause:

The rear wheel start to bump sideways under acceleration out of the corner.
The bike will squad too much (rear is too low), that will cause the front to loose grip.
Front suspension
Too much compression damping can cause:

Good result during braking.
Feels harsh over the bumps.
Too little compression damping can cause:

Strong diving of the front.
Adjustment advice:
Compression damping should be adjusted together with front fork oil level.





Spring ratio

Rear
Too hard spring ratio:

Gives easy turning into corners.
Makes the rear feel harsh.
Create poor rear wheel traction.
Too soft spring ratio:

Gives good traction in acceleration.
Creates understeer in entry of corner.
Makes too much suspension travel which will make it difficult to "flick" the bike from one side to the other in a chicane.
Will give a light feeling in the front.
Front
Too hard spring ratio:

Good under braking.
Creates understeer.
It feels harsh in the corners.
Too soft spring ratio:

Gives easy turning into corners.
Creates oversteer.
Can cause front to tuck under.
Bad under braking (diving).

Front fork oil level
First see manual. The modern front fork of cartridge type is very sensitive for oil Ievel changes, because of the small air volume Air inside the front fork works as a spring. The different level of oil effects the spring ratio from the middle of the stroke and has a very strong effect at the end of the stroke.

When the oil level is raised:
The air spring in the later half stage of travel is stronger, and thus the front forks harder.

When the oil level is lowered:
The air spring in the later half stage of travel is lessened, and thus the front forks are softer. The oil level works most effectively at the end of the fork travel.
Note: Adjust the oil level according to your manual.
Marinus

Good info above

Post by Marinus »

Try this site http://www.strappe.com/suspension.html
I found it very helpful. I found my suspension needed a lot of playing with before the bike and I got along. Someone had put in a 20mm spacer in the front forks which I found while changing the fork oil. As has been suggested above start with new oil, correct tire pressure and set your static and laden sag. Once all that is good then I would get into the grove :D ( get to know it) before playing with rebound and damping.
Post Reply