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I have the same problem on my SSS. Have twisted preload to max but still I keep bottoming out my front forks. Comp and reb are at 16 and 6 clicks out respectively. Do i really need to change forks?
How many kilometres have you done? How much do you weigh? Have you set the sag? Are you using a zip tie to confirm you are using all the travel? What sort of roads are you riding on? What is your riding style?

If the back of the bike is too high the weight transfer to the front will see you using more travel. It will also mean no free sag. Both are bad, and are usually a result of a 'stiffer is better' philosophy that leads to excessive preload (which doesn't change stiffness :oops:).

Your compression damping might be a bit fast, but as @RD52 says, compression damping complements preload but does not replace it. If you are running out of adjustment, the only sensible solution is to change the fork springs. If you are due for a suspension service do both at the same time.
 

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I dont get it. Could you explain this maybe?
Springs are designed to store energy and then release it. Spring rate is selected based on the energy it is expected to encounter.

Damping controls the speed at which the spring compresses and extends. It converts energy into heat.

Damping is sensitive to fork velocity, not position on the suspension stroke. Springs, on the other hand, store energy and are sensitive to the position in the stroke and not velocity. Therefore a shock absorbed by the suspension relies on the two working together. Compression damping cannot stop the suspension from bottoming out, and a spring cannot control the speed it compresses.

If you try to control travel by slowing the damping, all you end up doing is making the suspension harsher because the spring is robbed of its ability to store energy from whatever causes the suspension to compress.

The symptoms of excessive compression damping in the forks are:
  • good result during braking
  • feels harsh over bumps
  • tyre patter mid-corner
The symptoms of too much preload are:
  • hard to turn in
  • good braking performance
  • understeer (pushing the front)
  • harshness in corners
Notice that apart from the effect on brakes, the effects are different. Harshness in particular is contraindicative; it becomes harsh on both corners and bumps. Harshness is what suspension is meant to overcome, as it leads to a loss of traction. I wouldn't want to ride a bike that is hard to turn in, understeers, and then has tyre patter mid-corner.

And it's good braking, not better braking...
 
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How many kilometres have you done? How much do you weigh? Have you set the sag? Are you using a zip tie to confirm you are using all the travel? What sort of roads are you riding on? What is your riding style?

If the back of the bike is too high the weight transfer to the front will see you using more travel. It will also mean no free sag. Both are bad, and are usually a result of a 'stiffer is better' philosophy that leads to excessive preload (which doesn't change stiffness :oops:).

Your compression damping might be a bit fast, but as @RD52 says, compression damping complements preload but does not replace it. If you are running out of adjustment, the only sensible solution is to change the fork springs. If you are due for a suspension service do both at the same time.
The bike is pretty new, at around 3200km, I'm at 90kg with gear. Yes using a zip tie is how i found out. (Also I see a little oil on both my forks- can bottoming out damage the seals too?😶). A lot of speed breakers in my usual way to work. Ride moderately aggressive when out to ride otherwise easy going. Also It's raining this month here..so lot of muddy waters on the road.
And at last yes i have set sag, that's what I have been trying to correct in the front. Decreased the rear preload to get into the 30-35% sag figure.
Check out my current stats (attached) and the bike balanced here ....looks pretty balanced right?
 

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At 90kg, much like me, you are approaching the zone where you probably need to get springs with a higher compression rate. This is confirmed if you have set sag but have used up all of your preload. Some people with that sort of weight get away with it. Others don’t, and I didn’t. It all comes down to riding position and style. I, too, had to go for higher spring rates.

Your fork seals are leaking much earlier than most would expect. It’s probably a result of debris instead of wear, but dirt and grime can lead to premature wear. There are fork seal healers available that slide up between the seal and fork and divert debris away. If your seals are leaking they are worth a try.

If the leak cannot be stopped, bite the bullet and get the forks serviced. They will replace the seals and you can get them to replace the springs. It will only cost the cost of the springs over the top of replacing fork seals. Get it done by a reputable suspension specialist or race shop.

It’s not a Ducati thing, forks are usually provided by outsourced specialists, be it Ohlins, Marzocchi, Showa etc. But if you buy a motorcycle with fine handling characteristics you owe it to yourself to do what you have to do to maintain those characteristics.
 
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The bike is pretty new, at around 3200km, I'm at 90kg with gear. Yes using a zip tie is how i found out. (Also I see a little oil on both my forks- can bottoming out damage the seals too?😶). A lot of speed breakers in my usual way to work. Ride moderately aggressive when out to ride otherwise easy going. Also It's raining this month here..so lot of muddy waters on the road.
And at last yes i have set sag, that's what I have been trying to correct in the front. Decreased the rear preload to get into the 30-35% sag figure.
Check out my current stats (attached) and the bike balanced here ....looks pretty balanced right?
I’ll look at the video tomorrow, it’s not loading on my ipad.
 

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2021 Supersport 950
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Does anyone know which springs fit for the 43mm Marzocchi fork of the standard model?
 

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I’ll look at the video tomorrow, it’s not loading on my ipad.
The back seems a tad slow compared to the front, but it's hard to say; the guy compressing the suspension is bouncing instead of pushing.
 

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Gonna get the springs upgraded for sure. I was hesitating because there is not much expertise in my city(Pune) for such bikes and i have grown out of trusting the ducati service centre, they don't know much tbh. Gotta take a long ride to Mumbai i guess!
See if you can find a shop that specialises in race bikes rather than limiting yourself to Ducati dealers.
 

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Steve i was reading another post on one the threads and i got to thinking, what about the oil level? Doesn't that affect the overall stiffness of the fork?
It does. Adding a little oil will give you a bit more bottoming resistance.
The problem is that you're making the overall spring (steel + air) more progressive, which is bad.
Generally, when setting up bikes we'd rather use a stiffer spring and less oil, because it makes the suspension action throughout the stroke more linear.

If you're interested in learning about suspension setup I highly recommend Paul Thede's book, "Race Tech's Motorcycle Suspension Bible".

 

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@RD52 So we want the suspension progressive but not too progressive. Seems logical. Too much stiffness at end of travel is just like bottoming out i guess.

Thanks for the book suggestion. Sounds interesting. I might start this one after i complete reading 'Total control', btw you can get most books for free on zlib.org if you want.
 

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It does. Adding a little oil will give you a bit more bottoming resistance.
The problem is that you're making the overall spring (steel + air) more progressive, which is bad.
Generally, when setting up bikes we'd rather use a stiffer spring and less oil, because it makes the suspension action throughout the stroke more linear.

If you're interested in learning about suspension setup I highly recommend Paul Thede's book, "Race Tech's Motorcycle Suspension Bible".

Great book. I have a kindle version on my iPad and PC.
 

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2021 SuperSport 950S
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Does anyone here know how many turns the Ohlins front preload adjuster goes to full. I just did Sonoma and started out at 9 full turns in and ended the day at 15 and it was still bottoming the zip-tie. Comp started at 10 ended at 8. Rebound set at 5 didn't change during the day. Bike felt really good on the Pirelli Diablo Rosso Coarsa 2's at 28f, 30r, and the wear indicated the setup was fairly close.
I was going to have Dave Moss set up the bike but he wasn't at Sonoma Monday. He will be at Laguna Seca next Tue/Wed so I'll have him take a look at the set up and let him tune on it during both days. I have a feeling he will want me to go to a heavier springs.
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Thanks
I'm going to leave it just how I came off the track so Dave will have a better idea of what he will want to try. He likes to read the tires. He has set up our other track bikes and has always done good for us.
Photo of my son trying it out Monday going into turn 11, hard braking from fourth down to first. You can see full travel on the forks. He weighs more but I had the same problem at 185.
In the picture (lower) you can see the rear loaded with the front forks fully extended, don't think less preload would work but I'll see what Dave wants to do, got an idea he will want a stiffer spring on the shock.

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Thanks
I'm going to leave it just how I came off the track so Dave will have a better idea of what he will want to try. He likes to read the tires. He has set up our other track bikes and has always done good for us.
Photo of my son trying it out Monday going into turn 11, hard braking from fourth down to first. You can see full travel on the forks. He weighs more but I had the same problem at 185.
In the picture (lower) you can see the rear loaded with the front forks fully extended, don't think less preload would work but I'll see what Dave wants to do, got an idea he will want a stiffer spring on the shock.

View attachment 47004
View attachment 47005
I did springs in both the front and rear, I'm a heavy SOB, and it REALLY made the suspension shine.
 
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