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Discussion Starter · #1 ·
hello all

I have been changing sprockets (front and rear), adjusting sag and damping many times, and now i am somewhat confused. I have a feeling that the bike is too easy on steering, not so stable to hold a line on a long turn, and frequently wobbles when accelerating out of a turn. i am also afraid to come to a turn pushing the front anymore... i feel it will lose grip.

I need to start somewhere, and i feel that i need some feedback from people here. I like working on the bike on my own, but if i can't get info i will take it to a suspension guy. I think that i want to try increasing the trail (without buying the offset triples for now). My current setup is like this:

I weigh around 95 kilos (210lbs)
- sag set to around 35mm front, 22mm rear (i know i have to add to the rear, its on the schedule. maybe front too). oil front is fresh (ohlins r&t), rear is 2 years+ old.
- comp/reb close to stock. 7/9 front, 8/10 rear
- 15/39 sprockets, stock chain links (this as I've read, shortens wheelbase 4mm and adds some rear height)
- height. see pics please. i have no idea where i am or if something is terribly wrong, that's how i bought it:







I would like to try raising the rear as well as the front, one turn rear and one line lowering the forks, and ride it to see how it feels.

I 'd love some feedback on this, I've spent literally hours reading the past threads about geometry and the 1098 line. i am also considering buying some measuring tools.
 

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I don't think you'll find happiness with the stock setup. Most of that is due to rear end squat and that blasted progressive link. You're fighting with the front thinking that's where your problem is, but in reality, most of the issues are caused by the rear. Right now, you have way too much weight on the front end, no wonder it feels like shit. With your shortened swing arm length, you've actually pulled weight away from the front end and that has also led to the twitchiness.

First thing is to raise the entire bike up, running the front so low is giving you most of the issues for sure. I'd start by simply getting the bike pretty flat. It's hard to do this without the proper measuring tools, however if you have flat/level garage and a smart phone with a degree app, it can be easier to do this. A good starting place is the swing arm at 11 - 13 degree's of down angle. This of course is measured with the bike off the ground and parallel to the ground. Then you simply put your smart phone on the swing arm and measure using the degree app. My guess is, this will really get the rear end up high and the next step is to compensate by brining up the front. These bikes really like to be level with no rider on them.

If you want to learn more about this and have a few minutes to read something, here is a great information I've complied over the years which is public and free. Start with the "1089 Geometry Guide" and then you can look at the other stuff. Index of /suspension
 

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^here you go.... Dan Kyle knows about Ducati suspension set-up....................................... not a self proclaimed "internet expert" .... This post has been posted on numerous websites..... Lotsa info here, take your time and enjoy.....





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Joined: 28-December 06 Bike: 1098S 848 S1000RR


Posted 05 November 2009 - 09:44 AM

BEST setup for a 848 1098 1198

Kyle 30 MM offset triple clamps

Ohlins FGRT803 forks or
Comp 12 clicks out
Rebound 12 clicks out

Revalve of the OEM Ohlins forks to the same spec as the FGRT803 forks or
Comp 10 clicks out
Rebound 10 clicks out
Oil level with spacer installed 145 MM
Oil type Ohlins 1309 19 CsT @ 40 Degrees C

Ohlins 25 MM Cart kit for the Showa Forks
Comp 2 turns out
Rebound 12 clicks out
Oil level 165MM
Oil type Ohlins 1309 19 CsT @ 40 Degrees C

Height of forks using Kyle 30 MM offset triple clamp:
measured from the top of the triple clamp to the seam between the fork tube and the fork cap 6 MM to 13 MM.

The 13 MM will turn faster and be less stable.

Start in the middle 9 to 10 MM.

The heights will vary with rider preference and tire height differences.
Different tire brands have different diameters.

Kyle Track Link
Our track link requires the use of the DU788.
We mod the shock, making it shorter and changing the valve spec.
We have valve specs for the standard length OEM swingarm and the longer race swingarms.

With our track link and the OEM swingarm we start the damping settings at 10 click out for Comp and 10 clicks out on Rebound.

We also require a shortened Sato Height adjuster.
This will be set to about one thread showing on each end.
Using the ducati height adjustment measuring tool, we set the ride height at 235 MM, with a range of 230 to 240 MM.

Using the tool, this is measured with the rear of the bike FULLY extended, meaning there is NO weight on the rear wheel.
The measurement is taken from the top of the tool to the center of the rear axle.

Wheelbase length show be as long as possible.
The numbers measured from the center of the swingarm pivot bolt to the center of the axle should be as close to 504 MM as possible, with a range of 496 mm to 504 MM.

With the long swingarm the number is 510 MM with a range of 505 to 515 MM.

Rider sag with our Track Link should be:
Front 40 MM
Rear 30 MM.







In my opinion,
You have a number of things that are not so good on a stock 1098S.
They are in two parts.
Suspension.
Geometry.

The two can and do overlap, meaning that adjusting one can affect the other.

The one thing you want to be careful of is not adjusting one to fix the other.

The first thing to be corrected is spring rate and spring preload.

One more thing, IF you have the OEM 80 Nmm rear spring on your Ohlins shock and your Ohlins dealer told you to add preload, he does not know anything about the 1098S.
The OEM 80 Nmm spring already has too much preload on it.

The front fork springs are 10.0 Nmm
Depending on your weight they may be right, too stiff or too soft.

The same with the rear, but whatever the rear spring you use, you must reduce the spring preload by machining the preload nuts.

The OEM shock and forks are OK for street use, as far as the valving spec. But for ANY track use they are not any good.
You can revalve the OEM shock and forks.
Or replace them with the FGRT803 forks and the DU788 TTX36 Rear shock.

Here are rear shock spring recommendations with the OEM link.
To get the recommended 12 to 16 MM of spring preload the two spring preload nuts need to be machined. The plastic one on the 1098S will need to be replaced with an aluminum one.

1098 Shock Spring Recommendations
NOTE!!!!! This is with 12 to 16 MM of preload on the spring!!!!!!
Note weights are rider weight with gear, or take your weight and add 15 lbs for gear.

140-160 Lbs 80.0 Nmm
160-180 Lbs 85.0 Nmm
180-200 90.0 Nmm
200-220 95.0 Nmm
220-240 100 Nmm
240-260 105 Nmm
260-280 110 Nmm

For OUR Track Link stiffen rear spring by THREE 5 Nmm steps.So if you use a 90 Nmm spring with thye stock link we would go to a 105 Nmm spring with our track link.

These are the parts or mods I would recommend and the order I would recommend them.

Basics:
If doing any of the items below, or all, saves you from crashing ONCE, you have paid for everything and more.

If you are going to ride your bike at a race track, track day, or race day, it does not matter,
PUT ON RACE TIRES. I
Suspension
Install the correct springs for your weight.

Set the sag.
This is with the bike suspension fully extended and with the Rider on the bike. The measurement is the difference of these two points.
For the street:
40 MM Front
30 MM rear

For the track:
Front 40 MM
Rear with the stock suspension link 20 MM to 30 MM
Rear with the Kyle Race Link 30 MM

Bikes with Showa forks

Revalve with 20 MM valves Good
Install Ohlins 25 MM Cart kit Better
Install Ohlins FGRT803 Forks Best

Bikes with Ohlins Forks

For the street the stock valving rides well, it will have a lot of brake dive, and bike movement. Good
Install Kyle Superbike valving Best
Install Ohlins FGRT803 forks Best

Bikes with Showa Shock
Respring the shock for your weight Good
Install Ohlins DU515 or DU520 Better
Install Ohlins TTX36 DU788 shock Best

Bikes with Ohlins shock
Install the correct spring for your weight, Machine the shock spring preload nuts to reduce the preload on the spring. OK for the Street Good
Install DU515 or DU520 Better
Install TTX36 DU788 Best

Steering damper
With Ohlins damper Best
With no damper (848) install Ohlins damper
With base damper Install Ohlin’s damper

Triple clamp
Stock 36 MM Clamp OK for street use, you will find for track use the bike does not have enough trail and tends to run wide on the exit of a turn under acceleration.
Ride height with the stock 36 MM triple clamps will vary with the tires you are using.
The rear ride heights at this time should remain stock.
The front fork height can be altered.

As you RAISE the front ride height you are adding trail, more trail will allow the bike to hold its line exiting a turn. This by the way is exactly what the 30 MM offset clamps do.
If the bike is running wide you can raise the front of the bike by pushing the fork tubes down. This should be done in very small step, I would try 2 MM at a time. You can continue to raise the front of the bike by pushing down the front forks until the forks are flush with the top triple clamp.
As you raise the bike up it will require more effort to turn the bike.
As you raise the bike it will tend to “feel” like it is falling into turns instead of rolling into turns.

Or
You can install a Kyle 30 MM offset triple clamp, this adds the needed trail, and shortens the wheelbase which allows the bike to turn with little effort.
With our 30 mm offset clamps the fork height should be between 6 mm and 13 MM above our clamp. This again needs to be fine tuned depending on tires And rider preference. Again adjustments should be done in 2mm increments.
The 6 MM to 13 MM is measured from the top of our triple clamp to the seam between the fork tube and the fork cap.

Depending on the Tire you may have some rubbing if you are running 13 MM.

Suspension 101

Let me go over some basics on suspension. As if the basic stuff is not right no matter how much adjustment you do it will never work, Example it you front tire is at 10 PSI and the Rear 50 PSI do you think you can make the bike ever work right??
But everyone knows about tire pressure, the problem is everyone does not know about suspension, and must "gurus" do not bother to explain anything, a lot of times it is because the "gurus" do NOT KNOW.
My experience is if they cannot explain it to you, run away.

First always adjust your spring, do not tinker with the damping adjustments until the springs are right.
Front sag with rider 40 MM range 35 to 50MM
Rear sag with rider 30 MM range 25 to 40 MM.
Do not do anything until the springs and sag are right.

Now if, like in this case you are bottoming the bike, do not rely on a zip tie to determine this, if it is bottoming you will feel it.
The way NOT to stop bottoming, is more preload and or more compression damping, while this will slow down the dive it will make the bike ride harsh and not absorb bumps.

The way to stop it is by raising the fork oil level.
What does this do, the oil level does not have anything to do with the damping, as long as the fork valves are covered in oil they will work.
What changing the oil level does is REDUCE the amount of AIR in the forks.
Remember as you are compressing this air the PSI is building, just like more air in your tires, the more the forks are compressed the higher the PSI, the stronger the air spring.

This AIR is a powerful progressive spring, the less air the more powerful this air spring becomes. The great thing about the air spring is that is does very little in the first 75% of the fork travel, but when you approach bottoming out, this air spring acts as a second spring, holding the bike up. Without having to have a too stiff steel spring.

When adding oil to do this it MUST be done in very small amounts, usually 10CC per fork leg at a time. A very small amount of oil will make a big difference.
Rising rate suspension

What is it? Here is a good basic definition (taken from f1technical.net) with a few changes.

Rising rate suspension
A suspension system where the spring rate increases when the wheels move further in its travel. This action can be accomplished by configuring the geometric shape of the suspension, by using springs which change tension as they are compressed. The purpose of a rising-rate suspension is to maintain consistent ride and handling characteristics under a variety of situations: loaded or unloaded, straight roads or curves, and smooth roads or bumpy.

Ok, I will try and give a description on what is really does.

You have a rear wheel. This wheel has a travel usually around 120 MM on a Sportbike.

You have a shock, the shock travel is usually around 60 MM.

The two are connected by at least one link.

The link can have different designs allowing it to be Linear, meaning for each 2 MM of wheel travel the shock is travelling 1 MM, a 2 to 1 ratio.

Or you can design the link to be a progressive or rising rate link.

With a rising rate the options are endless. You can design it to do almost anything you want.

What we usually see is the travel, thru the first 50% (60MM) of wheel movement is very linear, meaning the for every 2 MM of wheel travel the shock is moving 1 MM.

Well what is happening in the next 60MM of wheel travel?? This is what is different.

What you may have is 60 to 70 MM of wheel travel the shock is moved 1.3MM
70 to 80MM of travel the shock is moved 1.6 MM
80 to 90 MM of travel the shock is moved 2MM
90 to 100 MM the shock is moved 2.5 MM
Etc

So what is happening, the shock and shock spring are moving more, they are moving at different ratios compared to the first 60MM of wheel travel.
So while it may take 60 lbs to compress each of the first 10MM wheel movements.
10MM 60 lbs
20MM 120lbs 60 lbs more
30MM 180Lbs 60 lbs more
40MM 240lbs 60 lbs more
50MM 300lbs 60 lbs more

Now it changes
60MM 78lbs more instead of 60 more 60lbs X1.3=78
70 MM 96 Lbs more 60 lbs X1.6=96
80MM 120lbs 60lbs X2.0=120

So what you feel on the bike is it takes more and more weight to compress the rear end.
This is great when you are selling a bike and have no idea how much weight is going to be on it, could be 120 lb rider 180 lb rider or a 180 lb rider with a 140 lb passenger. As this rising rate suspension can handle the different weights without bottoming out, which can cause a loss of control.


But when you know what the rider weights and it is say 180 lbs it works like crap as the rider does not weight enough to use all of the suspension.
As far as that 180 lb rider goes the suspension is pretty much doing the same as bottoming out, the suspension cannot use all of the available travel and stops moving, this causes a loss of traction and the tire, under acceleration, spins.

So what do we do, we make a new link that is more of a linear rate, less rising rate install a spring on the shock that is also a linear rate spring, and correct for that persons weight, and we get a more compliant suspension, that can use most or all the available travel, giving us more traction, hence the advantage at a track.

30 MM offset triple clamps

The advantage of these clamps is mostly at the race track, doing track days or racing.
The stock offset is 36 MM, these are 30 MM.
30 MM offset adds 6 MM of trail, this allows the bike to finish the turn better, allowing you to get on the gas sooner and hold your line better as well as better "feel" for what the front end is doing.
That same 6 MM change shortens the wheelbase making the bike turn faster and with less effort

53/53 MM Short stem

for 1098 Base, 1198 Base or any of the 1098/1198 series for use with the Ohlins Replacement R and T fork the FGRT803.

53/53 MM Long stem

These are for the 848 stock forks or the 848 using the FGRT803 forks.

53/56 MM Long stem or short stem.

These are for use with the FG511 Ohlins R and T forks.
This would be for the 1098S, 1098R, 1198S, or any 848/1098/1198 that you are mounting the OEM FG511 forks.
 

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Discussion Starter · #4 ·
ok thanks guys. both posts helpful. i ll read (again....sigh) the second and proceed with some measurements and modifications.
 

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Discussion Starter · #5 ·
I'd start by simply getting the bike pretty flat. It's hard to do this without the proper measuring tools, however if you have flat/level garage and a smart phone with a degree app, it can be easier to do this. A good starting place is the swing arm at 11 - 13 degree's of down angle. This of course is measured with the bike off the ground and parallel to the ground.
one small clarification. how do you measure the bike "flatness" in the end? supposingly you have the bike in the air (with a mid frame lift or something) how do you know its parallel? what is the horizontal line on the bike, let's say, that should be parallel to the ground?

and you set the swingarm angle from the height rod only right? ok 11-13 degrees... and then you put bike on the ground again and lift from forks until the bike is parallel again to the ground (the line on the bike again). so why setting it parallel on the first place in the air, if i am to do it again after i put it down?

or do i have it all wrong? :/
 

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ok thanks guys. both posts helpful. i ll read (again....sigh) the second and proceed with some measurements and modifications.

:) thanks to Dan Kyle. Kyle Racing....
 

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one small clarification. how do you measure the bike "flatness" in the end? supposingly you have the bike in the air (with a mid frame lift or something) how do you know its parallel? what is the horizontal line on the bike, let's say, that should be parallel to the ground?

and you set the swingarm angle from the height rod only right? ok 11-13 degrees... and then you put bike on the ground again and lift from forks until the bike is parallel again to the ground (the line on the bike again). so why setting it parallel on the first place in the air, if i am to do it again after i put it down?

or do i have it all wrong? :/
yeah, good luck with all that mumbo-jumbo...Tooned talk!!
 
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I don't think you'll find happiness with the stock setup.
Right now, you have way too much weight on the front end, no wonder it feels like shit. With your shortened swing arm length, you've actually pulled weight away from the front end and that has also led to the twitchiness.
First thing is to raise the entire bike up, running the front so low is giving you most of the issues for sure.
I could understand this style of 'contribution' leaving you more confused. Apparently you have too much weight on your front end, but not enough!
Both at the same time..
But there isn't really any 'blanket' advice on this that applies to all riders. We all ride differently. This is why racers spend days trying to achieve the optimum set-up for a certain circuit.
And why settings chosen by one rider do not translate to another.
OK. We are not highly paid international road racers - we just want our bikes to feel 'right'.
First up, it must be said that very fast lap times are set by the good guys on bikes which are not permitted to make the changes we can due to regulations. Like changing yokes and swing-arms. So it can be done on a pretty stock set-up.
But there has been a 'recipe' for Ducati superbikes which pre-dates even the first 1098 - it goes back to the days of Foggy and the 916 in'94. (WSBK permits these changes where most national series do not).That geometry 'recipe' has only been incorporated on the production bikes from the Panigale onwards - almost 20 years later..
The 90 degree "L-twin' suffers from an inherent limitation of weight bias. As in not enough weight over the front wheel.
The length of the engine, due to the 'laid-down' position of the front cylinder, limits the positioning of the centre of gravity (approximately around the crankshaft's position). Ideally this would be closer to the front wheel than the 1X98 engine permits.
The Panigale has partly addressed this by tilting the engine rearwards.
My solution to this is expensive, but I love it. That involves 'flatter' yokes/triples (30 mm offset) and a 15 mm longer swing-arm. This changes the weight bias from roughly 49% front and 51% rear, to about 52% front and 48% rear. Much closer to ideal.
I also run 15/39 gearing, but with a (pair of links) longer chain.
But you can improve it without this much expense. Getting a bit more sag on the back would help. If you can't reduce the preload further you should consider changing the spring, which has been fitted to permit you to carry a passenger.
Of course it is impossible to have a rear spring which is ideal for you solo, and also for a passenger. So if you change it you won't be wanting to take your girl for a ride.
Reducing unsprung mass - that which goes up and down with the wheels - will also help. Little things like replacing the front wheel spacers in aluminium, and using an alloy rear sprocket helps.
But you are at the start of a long and ongoing process. We all start out thinking we will just do this and that, and that will be enough.
But then the changes make the bike so much better that you continue. Titanium fasteners and expensive Ohlins components start arriving in the mail.
Your wife becomes suspicious and may leave you.:D
So be aware that this can become an obsession!
You may end up like me, with a bike which is sublime to ride, and weighs 23 kgs (almost 50 lbs) less, but which has had $30,000 spent on it.
Lucky my wife is understanding!
Best advice? Be careful who you take advice from. And only change one thing at a time.
Good luck with it. It can be a very rewarding experience.
 

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one small clarification. how do you measure the bike "flatness" in the end? supposingly you have the bike in the air (with a mid frame lift or something) how do you know its parallel? what is the horizontal line on the bike, let's say, that should be parallel to the ground?
I usually use the lines in the side of the cases to measure this. Using the same "angle" finding app, it allows you to fine-tune how level the bike is. Even though the cases aren't perfectly flat, they're the closest easy to measure object that is.

and you set the swingarm angle from the height rod only right?
Yep, the rod and preload are the only two things which make a difference in that area. Preload has much less of an effect, but it absolutely does.

then you put bike on the ground again and lift from forks until the bike is parallel again to the ground (the line on the bike again). so why setting it parallel on the first place in the air, if i am to do it again after i put it down?
You got it! You can't measure swing arm angle unless you know the bike is flat because if it's not, the smart phone app won't calculate for that difference. This is why most Ducati owners use what's known as a "ride height tool" which pushes into the side of the frame and gives you a measuring spot to work with. The bike doesn't need to be flat to use that tool.

If you read the documents and watch the video's I posted in that link above, you will learn a lot more about geometry from people who will teach you, instead of "tell" you what to do. I'm not giving you numbers because I can't touch your bike to find out what else is wrong. What I can do is give you instructions on how to set your geometry back to a base number. Then you can start reading and hopefully learn how to setup your bike properly.

Good luck!
 

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Discussion Starter · #11 ·
I could understand this style of 'contribution' leaving you more confused. Apparently you have too much weight on your front end, but not enough!
Both at the same time..
But there isn't really any 'blanket' advice on this that applies to all riders. We all ride differently. This is why racers spend days trying to achieve the optimum set-up for a certain circuit.
And why settings chosen by one rider do not translate to another.
OK. We are not highly paid international road racers - we just want our bikes to feel 'right'.
First up, it must be said that very fast lap times are set by the good guys on bikes which are not permitted to make the changes we can due to regulations. Like changing yokes and swing-arms. So it can be done on a pretty stock set-up.
But there has been a 'recipe' for Ducati superbikes which pre-dates even the first 1098 - it goes back to the days of Foggy and the 916 in'94. (WSBK permits these changes where most national series do not).That geometry 'recipe' has only been incorporated on the production bikes from the Panigale onwards - almost 20 years later..
The 90 degree "L-twin' suffers from an inherent limitation of weight bias. As in not enough weight over the front wheel.
The length of the engine, due to the 'laid-down' position of the front cylinder, limits the positioning of the centre of gravity (approximately around the crankshaft's position). Ideally this would be closer to the front wheel than the 1X98 engine permits.
The Panigale has partly addressed this by tilting the engine rearwards.
My solution to this is expensive, but I love it. That involves 'flatter' yokes/triples (30 mm offset) and a 15 mm longer swing-arm. This changes the weight bias from roughly 49% front and 51% rear, to about 52% front and 48% rear. Much closer to ideal.
I also run 15/39 gearing, but with a (pair of links) longer chain.
But you can improve it without this much expense. Getting a bit more sag on the back would help. If you can't reduce the preload further you should consider changing the spring, which has been fitted to permit you to carry a passenger.
Of course it is impossible to have a rear spring which is ideal for you solo, and also for a passenger. So if you change it you won't be wanting to take your girl for a ride.
Reducing unsprung mass - that which goes up and down with the wheels - will also help. Little things like replacing the front wheel spacers in aluminium, and using an alloy rear sprocket helps.
But you are at the start of a long and ongoing process. We all start out thinking we will just do this and that, and that will be enough.
But then the changes make the bike so much better that you continue. Titanium fasteners and expensive Ohlins components start arriving in the mail.
Your wife becomes suspicious and may leave you.:D
So be aware that this can become an obsession!
You may end up like me, with a bike which is sublime to ride, and weighs 23 kgs (almost 50 lbs) less, but which has had $30,000 spent on it.
Lucky my wife is understanding!
Best advice? Be careful who you take advice from. And only change one thing at a time.
Good luck with it. It can be a very rewarding experience.

I have been reading that the panigale is the beginning of stock geometry corrections for ducati and to be honest i was so so surprised i cannot still believe it 100%. You know, the question in your mind, "why...". Anyways. Thanks for all the additional info. Its a sum of what i have been reading the past months, with more details. I didnt know they tilted the motor on the pani!

When i bought the bike, living in Greece, i knew i wouldn't be able to sell it. The same ones are on the market for sale for years... I bought it because i wanted a supersport bike that i could keep for 20 years and work on it. I wanted something that its design would last for decades, and i bet on the 1098. I have all the time to slowly bring it to my riding preference through adjustments and parts, and i prefer to work on it myself. Heck i disassembled the motor on my first year to find out why it was burning oil :). I have been reading your posts of removing so much weight and its impressive (already have 520 and alu sprocket lol).



I usually use the lines in the side of the cases to measure this. Using the same "angle" finding app, it allows you to fine-tune how level the bike is. Even though the cases aren't perfectly flat, they're the closest easy to measure object that is.
which lines are these? could you post a picture maybe?

Yep, the rod and preload are the only two things which make a difference in that area. Preload has much less of an effect, but it absolutely does.

You got it! You can't measure swing arm angle unless you know the bike is flat because if it's not, the smart phone app won't calculate for that difference. This is why most Ducati owners use what's known as a "ride height tool" which pushes into the side of the frame and gives you a measuring spot to work with. The bike doesn't need to be flat to use that tool.

If you read the documents and watch the video's I posted in that link above, you will learn a lot more about geometry from people who will teach you, instead of "tell" you what to do. I'm not giving you numbers because I can't touch your bike to find out what else is wrong. What I can do is give you instructions on how to set your geometry back to a base number. Then you can start reading and hopefully learn how to setup your bike properly.

Good luck!
i have read most of them, time for a repeat. thanks a lot.

as it seems i have to buy some more stuff like stands (center maybe). I will probably start by increasing the sag numbers and then lifting both rear and front a bit, starting with the rear from swingarm angle.

Many thanks to you people here, who after posting the same stuff for years, you bothered posting once more :)
 

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which lines are these? could you post a picture maybe?
See the grid pattern on the bottom of the right side of the engine? Those lines are pretty flat in the grand scheme of things. Sure, sure, they aren't perfect, but good enough for this work.



as it seems i have to buy some more stuff like stands (center maybe).
This is how I do it… simply put car jack stands under where the swing arm pivot shaft goes. Works fantastic and doesn't cost much money.



I will probably start by increasing the sag numbers and then lifting both rear and front a bit, starting with the rear from swingarm angle.
Unfortunately increasing the sag numbers isn't a fix for anything. It's treating a symptom and not the root cause of the issue which is the progressive rear link and perhaps improper shock spring.
 

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Discussion Starter · #13 ·
See the grid pattern on the bottom of the right side of the engine? Those lines are pretty flat in the grand scheme of things. Sure, sure, they aren't perfect, but good enough for this work.

-thanks.

This is how I do it… simply put car jack stands under where the swing arm pivot shaft goes. Works fantastic and doesn't cost much money.

- ok i used the car stand for lifting the front, i did't know you could lift the rear from the swingarm pivot point!

Unfortunately increasing the sag numbers isn't a fix for anything. It's treating a symptom and not the root cause of the issue which is the progressive rear link and perhaps improper shock spring.

-yeah i know... still the sag is on the low side and i 'd like to try it
 

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Vehicle Crane Machine Automotive tire Auto part


A picture is worth a thousand words!!!!!!!...... :shrug:
 

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-yeah i know... still the sag is on the low side and i 'd like to try it
Yea maybe a turn or two of the preload adjuster.

Just be aware, there is a minimal preload required to make the shock function properly. It needs a certain amount of back pressure on the shaft (put there by the spring) to make the rebound circuit work properly. Sure, you can unscrew the adjuster to compensate, but all that's doing is opening up a bleed port for slow speed damping. All the high speed rebound is controlled by the circuit and not adjustable on the outside. So if you hit a bump in the road, the rebound will keep the rear end tucked in, instead of fully rebounding. If your on the throttle when this happens, it can lead to reduced traction.
 

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Discussion Starter · #16 · (Edited)
oh? i didn't know that. so there is no other way to find out if you are on the minimum preload required?

if i understood well, if you have the preload set too hard (very few mm of travel difference with rider on) it won't work right? or the opposite (too much sitting down when the rider is on)?

I think i will be ok though with the stock spring and my weight, with 30mm.

BONUS QUESTION: If i change the swingarm angle, do i need to set sag again? hmm. we will see.
 

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Guys, how about start by getting a simple ride height tool and set the rear up to where most track guys get their bike to . (Photos indicate the bike is to low in the rear), Front forks , usually2 rings through the top clamp. Base line the R and C settings and work from there?
 

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oh? i didn't know that. so there is no other way to find out if you are on the minimum preload required?
Öhlins recommends 10mm of preload with a linear (straight rate) link.

if i understood well, if you have the preload set too hard (very few mm of travel difference with rider on) it won't work right? or the opposite (too much sitting down when the rider is on)?
Yep! 100% accurate. Spring rate and preload go hand in hand. If you have the right spring, the suggested preload will give you the correct sag. Once you have those things dialed in, then the valving needs to be built for your riding ability. There are strict guidelines to how the valving and spring rates work with each other. Usually the springs are stiffer then the valving, but on an OEM setup, it could go the opposite because the spring rates are usually wrong. This is why simply unscrewing preload can cause the damping to be too stiff at certain times, completely independent of the clickers.

I think i will be ok though with the stock spring and my weight, with 30mm.
Absolutely no harm in trying!

BONUS QUESTION: If i change the swingarm angle, do i need to set sag again? hmm. we will see.
Most likely yes. Theoretically the two (sag/ride height) are completely independent, as you aren't adjusting the preload to make the rear end go up and down. However, because your increasing or decreasing the gap between the measuring spots where you get your sag number from, you could see a difference in the final sag number.
 

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I didn't read the entire thread but to the OP I would try raising the front by lowering the forks in the triple clamp at least two lines. Then try it. Don't change anything else. If you like that better then you have a lack of trail problem. Its easy and cheap to check and it makes a pretty big difference. I see you're showing three lines on the forks. If it was me I would make a large change up to say no lines showing. Then you can at least tell what happened.

If the front on turn in is an issue work the front geometry. Not the back.
 

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I haven't read all the comments, seeing as to it looks like it may turn out the same as countless other threads ruined. OP, do yourself a favor and read Dan Kyle's info on that (which Bob was nice enough to copy and paste on here). I have that link saved as a bookmark in my browser...for good reason! All the info you'll ever need on setting up an 848/1x98 for track or street, with multiple options to choose from. Sure it's a lot of reading, but what else you gonna do over winter? :)...it's a great starting point for any track day rider and novice racer. Unless you're a WSBK rider, the advice Dan gave in that write-up will work for you. He's a TRUE expert in this stuff, not like some others who had an 848 for a year, crashed it and gave up, and hasn't had a Ducati for like 4-5 years.
 
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