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Old March 12th, 2009, 02:39 PM   #1
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1098/1198/848 setup the right way

Introduction
In this write up, I'll be covering the chassis numbers/geometry of the 848-1198 and the "Chassis Kit" that I came up with to solve its shortcomings. Chassis settings/geometry is the single most important part of setting up your bike ...period. Throwing $20,000 worth of Superbike forks, TTX shock, etc. at a bike with a bad chassis setup won't do a thing for you. Chassis setup is the foundation of your motorcycle. You wouldn't build a million dollar house on a bad foundation, would you? Of course not, you would lose your house in short order, and, therefore, it would be worthless. All suspension action is based on or starts with the chassis geometry. If it is not right the rest of your suspension will not be.
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Old March 12th, 2009, 02:42 PM   #2
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The Importance of Chassis Geometry and Its Relationship with Springs
Even though I won't be covering springs in this write up, I would like to put their importance into perspective so your understanding of chassis setup is clearer.

In regards to performance, chassis geometry and spring selection represent 90% of your suspension. Geometry and springs aren't nearly as sexy as a TTX shock or a set of Superbike forks. But geometry and springs have a LOT more influence on how your bike works than anything else. And, by a large margin. All riders on the planet will go a lot faster with good chassis numbers and a proper set of springs-all while still using the stock forks and shock-than they would with the most expensive forks and shock you could find with bad chassis numbers and the wrong springs.

Even though good chassis numbers and correct spring rates are the most important parts of your suspension, when I'm at the track, I see a vast majority of the bikes have thousands of dollars wrapped up in trick shocks and forks, linkages, etc., all while running horrible chassis numbers. And these are just the ones I see walking through the pits. Out of the bikes that people bring over for me to set up/work on, 95% of them have spring rates way off from where they should be. And this includes the bikes with the trick suspension bits that were supposedly set up for their "weight." I couldn't possibly give you a number that would represent the amount of times I've heard "But I told the guy on the phone how much I weighed" when I tell them they have the wrong springs, but it would be a very big number.

Springs have a lot more to do with chassis setup and geometry than they do with "suspension." After you're working with a good chassis baseline setup, you have to set up the bike with the correct springs or you'll have done all that chassis work for nothing. Springs, just like geometry, are part of your bike's foundation. Of course, your suspension moves as you ride your bike. As it moves, the geometry changes a lot. Your springs dictate how far your suspension will move when a particular load is applied. For example, when you're hard on the brakes and setting up for a corner, you want to be down in the bottom few mm of fork travel. This isn't because the bike will brake better with the forks compressed, but you do want the forks compressed to a certain point when you turn it into the corner at the end of the braking zone. The more the forks are compressed, the easier it will be to turn, because when the forks are compressed, your steering head angle and trail numbers go down, which makes for easier steering. If you repeated the same braking drill and turn with fork springs that are too stiff, the forks won't be compressed enough. Then you'll find that, with the front of the bike riding too high, turning into the corner is a lot harder.

Most riders have raised or lowered their forks through their triple clamps at one time or another and know what it feels like when you change them only 5mm. Fork spring changes will have the same felt effects as moving the forks in the triple clamps. Springs will only compress so much for a given load. Imagine having fork springs that are so stiff that they leave you 30mm short of where you want to be when turning the bike into a corner. It's going to feel just like when you moved the forks in the clamps 5mm, but even more so (6 times more, to be exact). Springs can make or break your chassis setup. Get the spring rates working right, and your chassis geometry will do what you set it up to do. Getting the spring rates wrong will ruin your geometry in every instance that a load is placed on the suspension. Which is every situation except jumping the motorcycle. Spring rates affect your "net" geometry all the time. Spring rates should be considered and thought of as "soft geometry".

In conclusion, good chassis numbers are your foundation. They determine the starting point for all suspension movement. Springs, which can be thought of as "soft geometry," determine what the geometry of your bike is for a given load. Geometry and springs are co-dependant. If they aren't working well with each other, the bike will be incredibly hard to ride.

I'll be doing another write up on the 848-1198 shortly that covers spring rates, linkages, etc. I still have a few conclusions about the operation of the rear end of the bike that I'd like to prove by using multiple methods. I've done a lot of practical testing, and I'm 99.9% happy with my conclusions, but I like to be 100% sure. So, I'm working with a trig teacher at the local high school to prove my conclusions from a different angle.
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Old March 12th, 2009, 02:42 PM   #3
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Geometry, Its Parts, and Their Order of Importance

Everything that makes up the geometry of a motorcycle is incredibly important. But, everything is a compromise. While setting up, you can place a larger importance on some of the settings than others based on how you ride, what you are riding, where you're riding, etc. A good example of this is how you would set up the bike to run Barber compared to how you would set it up to run Mid Ohio. For Barber, you want to have a massive amount of trail, but you may want to run slightly lighter fork springs than you normally would. At Barber, you want the extra trail because you spend a ton of time on the side of the tire during a lap. In a lot of sections, you're even using the front tire to intentionally scrub off speed. For this kind of riding, you need a lot of trail so you know exactly what's going on with the front tire. Having a lot of trail, of course, has a penalty and that is slower/high effort steering. But, at Barber, it's a reasonable trade off, because Barber doesn't have a lot of corners where you need to slam the bike on its side lightning fast. Most corners at Barber have a nice sweeping entrance, which doesn't penalize you for having slower steering.

Slightly lighter fork springs at Barber may be a benefit to most riders too. Because you're on the side of the tire so much and making a lot of sweeping corner entrances, having a lighter spring will make those situations easier, because the forks will compress slightly more, which will speed up your steering a little and transfer a little more weight to the front tire. The downside of light fork springs is that the bike's stability during braking will suffer. But Barber doesn't have any "big daddy" braking zones. You do need to get hard on the brakes fairly hard going into turn one but because the exit of one is fast and downhill you don't need to threshold brake. Braking for turn five on the other hand does put a big load on the forks and having springs with a relatively high rate would be beneficial there. The thing is that you don't spring a bike for one brake zone/corner at the expense of the rest of the lap. Additionally you can blow five in a big way without it effecting your lap time because there are about a thousand lines through the corner and depending on what degree you blew the entrance you can simply pick another line to exit on. The top speeds at Barber are very low compared to a lot of other tracks, so it's possible to run lighter springs, because you're not spending much time on the brakes, and you're not braking from very high speeds.


Now, if you were going to Mid Ohio, you would want to go up on your spring rates front and rear compared to Barber. Mid Ohio is a "point and shoot" track. It has a lot of second gear corners that you trail brake to the apex, then square off the exit, and squirt your bike out as fast as possible. You don't spend much time at all on the edge of the tire compared to Barber. So you need higher rate fork sprigs to support the additional braking loads and a stiffer shock spring to cope with the corners being squared off and the throttle getting whacked open on corner exit. In addition to that, Mid Ohio has a 175 mph (on a 1000cc bike) back straight which leads into a second gear corner. That's a huge demand on the brakes and the fork springs. It's also one of the only spots to pass on the track.

If your bike is set up weak for that brake zone and the entrance to the following corner, you'll find yourself getting passed regularly there, and you won't be able to get spots back in the same spot. And, because the track is so hard to pass on, you may not get a chance to pass anyone else even if you can run a second a lap faster than they can.


Depending on how you ride, where you are, the strengths and weaknesses of your bike, etc., the following list may not be 100% accurate. But I wanted to put this in here so you'd have an idea what takes precedence..most of the time. For the most part, the items toward the top of the list are getting set up without compromise. The items at the bottom of the list are the ones that have been deemed compromise able. Use this list as a suggested outline, not "the last word." There are a limitless number of variables when it comes to setup. Staying flexible in your thinking and abilities is a must.

•Trail
•Swingarm angle
•Weight distribution
•Wheelbase
•Swingarm length or % of wheelbase
•Ride height/capsize/center of gravity
•Steering head angle
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Old March 12th, 2009, 02:45 PM   #4
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Initial Impressions of the 848-1198 Chassis
(this covers every 848, 1098, 1198, S, R, etc.)
It seems like an eternity since I first swung a leg over a 1098S and took it out on the track for the first time. I had very high expectations and, at the time, was looking for an excuse to buy one. Long story short, I was back in the pits in 15 minutes staring at it while it was sitting up on its stands. I didn't like it at all. I managed to push it up to about 80% and anything after that just turned pear shaped. Going any faster than that was getting scary and wearing me out. A sure sign of chassis issues. The only way the bike could be ridden at any sort of fast pace was to trail brake it to death, almost folding the front, parking it at the apex, and then point it where you wanted to go, waiting longer than you would need to on any well set up chassis, and then getting on the gas. The bike wouldn't get anywhere close to finishing a corner on the gas. Riding like this was very, very hard to do because it had next to zero front end feel and judging the limits of the rear contact patch was next to impossible. Four or five laps of riding 80% was enough to zap all of my energy. It felt like I had ridden an hour on a well set up endurance bike. At that point, I knew that I was not going to solve what problems the chassis had trackside. Sure I could have thrown lighter springs at it and played around with the geometry, but it would have taken all day and I was certain that it needed more than a little tuning. It needed to be gone through top to bottom, front to back.

From my short ride, I was certain of a few things right off the bat, which gave me some things to think about on my drive home.

It was sprung like a brick front and rear. Despite running everything "full left" (taking out all the compression and preload) on the forks, I couldn't get close to using all the travel, which is the first thing I try to do when setting up the front end of a bike. The rear tire would spin up everywhere even at very light throttle applications. And, to make matters worse, when it spun the tire it would go sideways instead of forward. If a chassis is set up correctly, you can spin the tire all day with very little fear of it stepping out, hooking up, and launching you to the moon, the dreaded highside. The bike being sprung like a brick explained why the bike wouldn't use all the fork travel and why the tire spun like it was on ice. What didn't make sense was that, despite being sprung like a brick, it still wouldn't finish a corner on the throttle. A bike that won't finish a corner on the gas has one or both of two problems. It's either sprung too light, which I already knew wasn't the case, or the swingarm doesn't have enough angle in it. It's not very often I need to work with a modern bike that has a swingarm angle that's way off the mark. I was very surprised.

When I got back to the shop, I got the bike up on a lift, got out all my jigs and lasers, and started measuring. The bike needed to be baselined to see how it compared with the "basics." The basics are a range of chassis numbers that all superbikes will fall into. There's not that much difference between every superbike made. It's not very surprising, they're all working toward the same goal. Yes, one manufacturer will do this and one will do that, but you'll never see a superbike that's running a 30 deg steering head angle when everyone else is near 24 deg. There's a reason for that, it wouldn't work. If you look at the basic chassis numbers for all of the popular superbikes, you'll find that they fall into a fairly narrow window.

At this point, I would like to thank Joe. He entrusted me with his brand new 1098S so I could do some testing with it and prototype some parts, if needed. If Joe hadn't let me use his bike, I would have needed to buy one. It took me a long time to be 100% confident with my setup findings (because they ended up being so simple it didn't seem possible). At this point, I've had his bike for almost two years, and all that he asks of me is that I meet him at the few track days he wants to ride at per season. Again, Joe deserves a big thanks.

Before we get to what the bike measured out at, it would be a good time for you to review the terms that are used when talking about chassis setup. These terms are defined in the Glossary which can be accessed through the menu in the opening page.Â
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Old March 12th, 2009, 02:45 PM   #5
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Chassis Geometry as Set Up by Ducati
Keep in mind that all measurements need to be and have been taken with the suspension fully extended (not compressed at all). This keeps things apples and apples.

848/1098/1198

Ducati's Published Chassis Specs (taken from Road Racing World Feb 2009):

•Trail 97mm
•Swingarm angle NA
•Steering head angle 24.5 deg
•Swingarm length 505mm
•Wheelbase 1430mm
•Weight distribution NA
•Weight 377lb
Ducati didn't have its trail number listed in any of the press material I could find online or on ducati.com. I find it odd that they've published so little chassis information. In the past, this wasn't the case, and all the other manufacturers throw specs at you like they'll get a prize if they hit you in the head with them.


What You Actually Get Off of the Showroom Floor

•Trail 91.5mm
•Swingarm angle 7.8deg
•Steering head angle 24.7 deg
•Front ride height 711.5mm
•Rear ride height 230mm (measured with DOS tool)
•Swingarm length 505mm
•Wheelbase 1447mm
•Weight distribution 49.5f/50.5r
•Weight 401lb
So What Does This Mean?

First, it means that Ducati's published/claimed numbers aren't accurate. But, that's no surprise, every manufacturer has been "optimistic" with their weight and horsepower figures since the beginning of time. It stands to reason that their chassis numbers would be incorrect as well.

Of course, all of the above data doesn't do you much good unless you have a benchmark or set of basic measurements to compare them to. For example, the 848-1198 has a swingarm angle of 7.8 deg. What does that mean to the average Joe? Well, probably not much. Unless that average Joe has something to compare it to, it's effectively useless information. The good thing is that we're in a bit of luck with this chassis.
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Old March 12th, 2009, 02:46 PM   #6
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How the 848-1198 Chassis Numbers Stack Up Against the Benchmark
Ok, now that we know the 848-1198 chassis is for all intents and purposes identical to its predecessors, let's take a look at some more data. These numbers are taken directly off of my 999R, which is fully developed. I went as far as to have some VERY fast riders (lap record fast) ride it and give me their setup input to see if I left anything on the table. Aside for some minor ride height and spring changes to suit particular riders, none of them ended up sticking with the changes we made to the bike though. Everyone ended up back where we started. Keep in mind that these numbers are nowhere near the stock 999R's chassis numbers. But the only non-stock part that was needed to achieve these chassis numbers was a set off offset triples.

Completely Developed 999R Chassis Numbers

•Trail 101.2mm
•Swingarm angle 10.4deg
•Steering head angle 23.3 deg
•Front ride height 715mm
•Rear ride height 255mm (measured with DOS tool)
•Swingarm length 505mm
•Wheelbase 1445mm
•Weight distribution 52f/48r
•Weight 376lb
The 848-1198 of the Showroom Floor Numbers Again

•Trail 91.5mm
•Swingarm angle 7.8deg
•Steering head angle 24.7 deg
•Front ride height 711.5mm
•Rear ride height 230mm (measured with DOS tool)
•Swingarm length 505mm
•Wheelbase 1447mm
•Weight distribution 49.5f/50.5r
•Weight 401lb
*Tire height was factored in for this comparison.

So what do we have here? We have one seriously screwed up Ducati 1098S, that's what we have. The numbers are so bad that I checked them three different times, calibrated my lasers, measured again, and then set all my tools up on a different bike that I knew the geometry of. The tooling was fine.

As wacky as the numbers are, they do explain exactly what I was feeling while riding the bike, though.

The trail, which is dangerously low, explains why the bike turns like lightning. It's nice to have a bike that turns well, but not at the expense of trail.

The swingarm angle, which is very flat, explains why, when the tire spun, the rear end of the bike stepped out and tried to pass the front of the bike. The flat swingarm also contributes to the tire spinning earlier than it should. And, finally, the flat swingarm angle prevents the bike from finishing a corner on the gas.

The steering head angle is actually fairly reasonable but a bit on the "slow" side by today's standards. That's ok, the lack of trail makes up for the slow steering that comes from having a big steering head angle (that's a joke).

The front ride height is also fairly reasonable.

The rear ride height is INCREDIBLY low! It took me a while to figure out why (more on that later). The incredibly low ride height is why the swingarm has such a shallow angle. The low rear ride height is the cause of the flat swingarm angle and the problems associated with that. When I was measuring the rear end, I started to get worried about how drastic the fix for it was going to need to be. The low rear ride height actually "creates" more trail. Fixing the rear ride height, which would also fix the swingarm angle, would actually make the trail worse, and it was already out of the ballpark. So, fixing the ride height would fix the swingarm angle and would get the steering head angle going in the right direction. But, at the same time, it would make an already dangerously low trail number even lower.

The swingarm length is spot on for a Ducati chassis, which is a relief. Of course, the length will change when the gearing is changed, but 505mm is a good starting point that will keep the bike in an acceptable range. In the past, a single-sided swingarm that was too short (748-998) was an expensive problem to have. And even on the 749-999 as delivered, you had to add chain links to get the swingarm length you needed.

The wheelbase is what it is. It would be nice to have it down in the low 1400s though. We'll be reducing the wheelbase a bit though when setting up the bike.

The weight distribution is not so hot. In this day and age, 52/48 is a good place to be (the 06 and up Yamaha R6 is 52/48 off of the showroom floor), and some of the MotoGP guys are running them as far as 54/46. The good thing is that we know exactly why the weight distribution is so far off. With the rear ride height slammed, there's no way to get the weight distribution in the right galaxy. The solution? More ride height. Having too much weight on the rear wheel also contributes to the bike having very light steering. But, just like the low trail number, you don't want light steering at the expense of good weight distribution.

After I had the above information, it was time to start doing something to improve the setup. It's obvious that the rear ride height was the first thing to go after. It will improve the swingarm angle, steering head angle, and weight distribution but will hurt the trail numbers. Trail numbers can be fixed with triple clamps though. So, with all the measuring tooling still mounted up, I started to raise the rear ride height. Or, to be more specific, I tried to raise the rear ride height. As usual, even though the bike had only 400mi on it and had never been wet, the ride height adjuster was "welded" together. I would have thought after 13 years (the adjusters have been a problem since the 916), Ducati would have addressed this. After I had the ride height adjuster broken loose and filled up with Anti Seize, I started to add ride height. After I reached the point where the ride height adjuster was as long as it could safely be, I measured everything again. The swingarm angle and steering head angle were getting better, and, as expected, the trail got worse. The problem was the ride height, swingarm angle, and steering head angle were still not in a good place. I continued to raise the ride height with the OEM adjuster, but it wouldn't have be safe to ride on. You want to have 1.5 times the thread diameter of the end bearings threaded into the aluminum part of the adjuster per end - at a minimum, 18mm. Oddly enough, and just like magic after I got the ride height to where I wanted it, the swingarm and steering head angles ended up right where I wanted them to be, too. Just like it was designed that way, weird (note sarcasm). Of course, now the bike had a tragic trail number.

Chassis numbers after adding rear ride height

•Trail 88mm
•Swingarm angle 10.7deg
•Steering head angle 23.4 deg
•Front ride height 711.5mm
•Rear ride height 255mm (measured with DOS tool)
•Swingarm length 505mm
•Wheelbase 1447mm
•Weight distribution couldn't be determined because the bike was all set up with the measuring equipment and on the lift
Now I was looking at a chassis I knew was "in the zone," but it was dangerously short on trail. There was one more available adjustment that could be made to increase trail and that was to raise the front ride height. It wouldn't affect the trail much, but I think it's good policy to maximize the stock components before replacing them. I set the front ride height at its maximum setting of 715mm. That's not the absolute maximum height that you can get out of the front end, but, if I went any higher, the forks would start to recess into the clamps, which is functionally not a problem but isn't the most attractive thing in the world. Raising the front ride height got me just a tick under 1 more mm of trail and put the overall trail number at 89mm. The swingarm angle and steering head angle changed because of the additional ride height, but the changes are so small it's nearly impossible to measure.

At this point, the stock components have been maxed out and then some. A ride height rod would need to be made to achieve the rear ride height I had dialed in. I was tickled pink with all the chassis numbers though, except the trail. I had the bike set up virtually identical to well set up 748-999 chassis, which, even after all these years, can still run at the front of the pack. All the bike needed at this point was a set of triple clamps with less offset to get the trail set correctly. And, the math to figure that out is a piece of cake. If you want 1mm more trail, you want to use triples that have 1mm less offset. To get to my target of 100mm of trail, the bike would need triples that had 11mm less offset than the stock ones. The stock ones are 36mm so I needed some 25s to get the numbers I wanted. An added bonus is that, since the bike no longer has an adjustable steering eccentric (I know the R does, but it's a different insert unlike the old ones that you simply rotated 180 deg), every mm you "chop" out of the clamps also comes out of the wheelbase, which is something that the bike also needed. Triples with less offset also improves the percentage of the wheelbase that's swingarm. And, finally, because you're moving the front wheel "under the front of the bike more," you get a bit more front end weight bias, which the bike can als
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Old March 12th, 2009, 02:46 PM   #7
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Final Chassis Numbers with the DOS Chassis Kit
•Trail 100mm
•Swingarm angle 10.4deg
•Steering head angle 23.3 deg
•Front ride height 715mm
•Rear ride height 255mm (measured with DOS tool)
•Swingarm length 505mm
•Wheelbase 1436mm
•Weight distribution 52f/48r
Do those numbers look familiar? They should. They're your classic "Good Ducati Superbike Numbers." I was quite surprised that getting the chassis dialed in was so easy. No one else I knew of was going anywhere near the direction I was. It seemed fairly logical to me that, if the bike was set up like its predecessors, it would work great. And, when I attempted to set it up like that, all the numbers immediately corrected themselves. There are two catches to the 25mm offset triples though. First, when the forks are fully compressed, the front tire will contact the radiator and oil cooler cover. I solved the radiator issue by making an offset lower bracket for it. The radiator simply rotates at the top mounts. The oil cooler cover, on the other hand, had to be slightly notched to get the desired tire clearance. It's not a big cut, but the "perfectionists" may not be too happy about it. The Ducatis have always had front tire contact issues when set up correctly though. In the past, you had to stop pulling the front wheel back when it contacted the cylinder head/cam cover. The new motors have shorter cylinders/heads, so that's not an issue anymore. It's a good thing, too; it's a lot easier to address the radiator and oil cooler cover issues than try and move the cam cover (which you can't). It's actually too bad Ducati didn't shorten the frame up by 10-15mm and then add that 10-15mm to the swingarm length. The room is there for front tire/cam cover clearance, and shortening the frame/extending the swingarm would help the basic chassis layout tremendously.

Riding Impressions
I was quite nervous the first time I took the bike out on the track. I'd been working on it and waiting for spring just about 6 months before I had a chance to throw a leg over it. I really didn't want to get out on the track and find that I created some sort of monster that was unrideable. I took a session running at 75% to figure out where all the levers, pedals, and pegs were located and to scuff in the new tires. Aside from some control placement issues, everything was as expected. It felt like a 748-998 more than a 749/999 because of the high seat height. It was kind of nice, I always liked the "stink bug" stance of the 748-998, and, even though the 749/999 is a great bike, I preferred the 748-998's "sitting on the bike" riding position opposed to the 749/999's "sitting in the bike" riding position. After the session, I came back in and moved the controls around so I could manipulate them better and went right back out on the track. Over 3-4 laps, I started upping the pace a little per lap to see what the bike was going to do to or for me.

I was cruising around in the 26s (at Grattan) just hanging out and familiarizing myself with the idiosyncrasies of the bike when a couple of guys with yellow plates came by, so I figured it was time to step it up a bit. I followed these two guys around for another two laps noting what the bike was and was not doing, which wasn't much. The only two things that stood out were that the brakes were violently grabby and needed a less aggressive pad with less bite and that it was almost impossible to get on the gas smoothly and not upset the chassis. The bike has a ton of torque and, unfortunately, it hits like a ton of bricks. To truly go fast, the throttle bodies would need to be set up real good and maybe some cam timing changes to push the power up further in the rev range. The power was hitting hard enough on the edge of the tire to either make it spin or it would put an input into the chassis that was a bit uncomfortable. As far as suspension impressions go, I really didn't have any. It felt like..well, a set up Duck. My lap timer only recorded the first couple of laps, so I don't know what I was doing out there, but I didn't care much either, I was just shaking the bike down.

Once back in the pits, I played around with the handlebar placement a bit and took some preload and compression out of the forks because I wasn't using them all yet. I threw the warmers on at 175 deg and hung out and told lies about how fast I was for 20 minutes or so while waiting for the next session. I knew the next session was going to be the one where I was most likely to do my fastest laps. I was all warmed up but not tired, and the tires had the right amount of time on them. I set the tire pressures hot before I went out on the track for the next session and started to get focused on doing a few fast laps. I managed to get on the track first and put my head down right away. The tires were perfect, so it was a good time to see what I could get out of the bike. I had totally clear track for the first flying lap which was a 25.2. Not bad, I wasn't riding very hard yet. I didn't have anyone hold me up on the next lap either and knocked down a 23.7. I was pleasantly surprised, I wasn't even riding that hard and the "no crashing light" was on bright. Remember, not my bike. After seeing the 23.7, I wanted a 22, which would be a lot more than I expected for the first time out on the bike. I attacked the next lap hard but got held up through 6-7-8 by the track day guys and only managed a 24.9 on that lap. As I was crossing the line at start/finish I could see there was no one on the track between me and the jump, which meant, unless someone got on at 5, I would have another clear lap. So I tried to relax, hit all my marks, and put in a nice smooth lap. Well, it paid off. That lap was a 22.2, which is very good for me at a track day and taking into account I was riding someone else's bike. I rarely get my lap times down that far even during race practice. Low 24s are the norm. There's a switch in me somewhere that only turns on when the green flag drops. I always go a lot faster during races than during practice.

But you're not reading this to know what kind of laps I rode. You want to know how the bike works. And the answer to that is "great." It feels just like it should, a well set up duck with a high seat height. Despite having a 100mm of trail, it still turned very fast, and I was still running the short OEM bars. A wide set of aftermarket clip-ons would reduce the bar effort even more. The bike didn't wear me out at all, which was a big change from when I first rode it. And I never felt like I was even pushing that hard. I know there's more time in the bike, too. If I spent a couple of days just tuning, I know I could make it even easier to ride. The biggest things I wanted to address had nothing to do with the suspension though. It needed some less aggressive brake pads, and it needed some tuning to smooth out the throttle application on the side of the tire. And a short throw throttle would help out tremendously. It felt like I twisted it around twice to get it to WOT.

Since the first test I rode/tested with the bike at two more track days to rack up some seat time and make sure that I was 100% satisfied. Of course I goofed around with settings between every session to see what would happen but aside from a little nip here, and a little tuck there I don't feel the need to make any changes to the bike.
The forks are the stock Ohlins except I'm running .925kg fork springs and they've been rebuilt/had an oil change.

The shock is the 46mm Ohlins that came stock on it, and I updated the valving package to current specs. I'm running a 7kg shock spring.


I'm running the stock shock link/rocker arm.

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Old March 12th, 2009, 02:47 PM   #8
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Poking Holes in My Theory
The above setup process may seem like it was difficult to do, and I would like to make the claim that I'm a genius for doing it like I did. But, it was actually very easy after I determined that the chassis/engine case layout was the same as previous superbikes. It was so easy, in fact, that I thought I may be missing something big and obvious. I also thought it was odd that no one else had come up with something similar. In fact, everything I had seen floating around on the "net" pointed toward lowering the rear ride height. Not that I put a lot of stock in "net chatter" though. I spent a lot of time looking for holes in my conclusions because I just couldn't believe that Ducati released a bike that was so far from set up right. Ducati has always been real bad about setting up their bikes, but not nearly this bad. The two biggest problems with the chassis as delivered were the rear ride height (which screwed up the swingarm angle and weight distribution) and the trail.

I spent a ton of time on the net looking at every picture I could get my hands on of the WSBK bikes. I would have thought it wouldn't have been very hard, but it took me forever to find a perfect side shot of one of the team bikes while at the track (a real bike, not a display model). I wanted to see what the WSBK team was running for swingarm angle/ride height. Of course, I wouldn't be able to tell the difference between 10 and 10.5 deg, but the difference between 7 and 10 deg can be seen from a mile away. After I found the shot I needed, I was in luck. The picture was huge (2500 pixels plus); I took it up to the print shop and got the rear end of the motorcycle printed out at a 1:2 scale. When I got back to the shop, I put it up on the wall, leveled it out and then took some time measuring angles.

Of course, having the picture was not as good as having an actual team bike to measure, but it was more than good enough to verify my conclusions. As measured, everything came out to be within a half a deg of what I had set up the shop bike to. Needless to say, I was glad to see that. I knew that my conclusions were virtually identical to what they were running on the factory race bikes. Then, when I went to the Milan Motorcycle Show a few weeks later, I got lucky. There was a team bike in the Ducati display that was clearly ridden, and it had a lot more than a 7 deg swingarm angle. It also had a set of clamps on it that had very little offset. So little, in fact, that they had moved the steering damper to the front of the top triple. I'm sure the reason they moved the damper was not entirely because of the clamps being pulled back so far, the fuel tank was bigger, too. But it was valuable information.


After verifying my findings by comparing them to the picture of the factory bike and seeing the bike in Milan, I was satisfied that I went in the right direction.

At that point, all I had to do was wait for it to warm up and turn into spring (spring 2008, the testing I outlines above) so I could do some on track testing. While I was waiting for things to warm up, I started to ponder why Ducati shipped the bikes out set up like they were. I was confident that my baseline setup was good, but not knowing why Ducati shipped them out like they did left a little bit gnawing in the back of my head. What was the reason? Was I missing something fundamental that needed to be present to make the bike work? Without an explanation of why they were set up like they were I still had doubts. Keep I mind it was also too cold to ride so all I could do is think about the setup, I couldn't go out and test it yet.
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Old March 12th, 2009, 02:47 PM   #9
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Why Did Ducati Set Them Up Like They Did?
Tank Slappers? My first theory why Ducati did a set up with so little ride height was that this was their most powerful bike ever released, and they didn't want to have "gentlemen riders" tank slapping themselves off the side of the road. Remember the 1997 Suzuki TL1000S? That bike was single handedly responsible for the entire industry making steering dampers an OEM item. The TL would tank slap like crazy when the bike got "into the cams," and a lot of people ended up in the ditch. I was thinking Ducati took out a ton of rear ride height, because it would make the bike less likely to get in a tank slapper situation. It seemed reasonable to me. As delivered, the bike is reasonable for road riding (sane road riding), and maybe they figured the track riders would figure out how to set it up or something. I chewed on this for quite a while but couldn't get comfortable with this being a solution for Ducati. There are a lot of ways to keep a bike from tank slapping that won’t ruin the rear end of the motorcycle.

Wheelies? My next thought was that maybe Ducati took all the ride height out because they knew the bike would have much more controllable wheelies that way. The 1098 has so much torque there's no doubt that a lot of riders will soon be introduced to the "surprise wheelie." Now don't get me wrong, low rear ride height won't prevent a bike from sending the front wheel skyward. The low ride height will actually make it wheelie sooner, but they will be a lot lower and controllable than the wheelies you get when you have a high ride height. The wheelies you get with higher ride height won't come up as soon as they will with low ride height, but, when they do come up, they snap up fast and hard. Of course, this is great if you want to ride wheelies all day but only a very small percentage of riders can or want to ride a 12 o'clock wheelie that just snapped up on them. Now don't get me wrong, setting the ride height up higher than what the bike had stock isn't going to turn it into a wheelie death machine. 99.9% of the riders out there will actually benefit from the wheelie characteristics of added ride height. With the added ride height, it's harder to wheelie, it's just when it does the wheelie what you get won't be a little baby one. I assure you that, with the higher ride height, the bike won't be trying to flip over backward all day. With the bike set up with the chassis numbers I outlined above, I have to intentionally wheelie the bike to get it to do one.

Bingo! It took me some time, probably because it was staring me in the face. But I finally figured out why Ducati set the rear ride height so low. Seat height. It was right in front of me the entire time. As soon as I thought of it, I measured the seat height and referenced it off of the swingarm pivot (remember, the swingarm pivot is "absolute zero"). At the point where the seat meets the tank, the seat is already 18mm higher than a 749/999. That right there is almost an inch more seat height. To compound the problem, the 848-1198 seat angles upward sharply toward the rear of the tail where the 749/999 is basically flat. An average 5'10" American will take up at least 250mm of the seat measured from the tank backward. The seat height 250mm behind the tank is another 50mm higher. So what you have is a seat that starts 18mm higher than a 749/999 (which doesn't have a low seat height) and slopes up another 50mm. Even if you just took those two numbers and averaged them to give the slope of the seat a "value," the seat height compared to the swingarm pivot would be 34mm higher than a 749/999. That's one very high seat and, depending on how big you are or how you sit in the seat, it could be higher because you sit more toward the rear.

My theory on how this all came together is this. The Ducati design team gave it everything they had and were determined to put out a bike that wouldn't have the love/hate looks that the 749/999 had. Their target was to make the bike they should have to follow up the 748-998. I'm sure everyone agrees that Ducati nailed the looks this time around. But with those looks came some compromises. Getting that giant exhaust to run up under the tail and fit all the suspension linkage in there (that has been extremely crowded by the massive swingarm) made it necessary to raise the seat height. The bottom line is that there's only so much room, and Ducati jammed a lot of really big stuff in there. Just the exhaust and the swingarm are enough to force the seat higher. And, on top of that, the tail does look good angled up toward the rear (the 748-998 and 749/999 were pretty flat in comparison), which pushed the rear of the seat even higher. I suspect that after Ducati had the first prototypes finished and had good chassis numbers plugged into them (there's no doubt they know how to make their bikes work perfectly...just look at the 749R, it came with everything you need as far as chassis goes right out of the box and that included offset triples), they realized that the seat height was way too high for what's considered reasonable for the buying public. Well, there's no way that the design side was going to change the whole look of the bike because of the seat height. They really did nail it. I'm sure they made the decision to simply lower the rear ride height to achieve a reasonable seat height. It wouldn't affect street riders much at all because you simply can't ride that hard with any sort of sanity. They could do anything they wanted as far as rear ride height on the race bikes. And maybe they thought that the track day riders/racers would figure out a solution. The short version, I think Ducati decided to sacrifice a lot of rear ride height and, therefore, chassis performance to get the seat height down to a point where you don't need to be 6' tall to swing a leg over the tail. All you have to do is look at the numbers. The ride height that needs to be added to the rear to get a good swingarm angle is almost exactly the same as you would have to lower the rear to get a competitive (compared to other superbikes) seat height. I've been around Ducatis for a very long time, and lowering the rear to get a target seat height, even if it sacrifices chassis performance, sounds like standard operating procedure for them.

Secondly, I suspect that, after Ducati had the whole bike put together, they figured out they were short on trail, too. It's very possible that Ducati was already locked in (I'm fairly certain the frames are not made in house and their supplier may have already started making them or made the tooling) as far as the steering head placement was concerned, and lowering the rear would help because it would add trail.
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Old March 12th, 2009, 02:48 PM   #10
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Riding Impressions
I was quite nervous the first time I took the bike out on the track. I'd been working on it and waiting for spring just about 6 months before I had a chance to throw a leg over it. I really didn't want to get out on the track and find that I created some sort of monster that was unrideable. I took a session running at 75% to figure out where all the levers, pedals, and pegs were located and to scuff in the new tires. Aside from some control placement issues, everything was as expected. It felt like a 748-998 more than a 749/999 because of the high seat height. It was kind of nice, I always liked the "stink bug" stance of the 748-998, and, even though the 749/999 is a great bike, I preferred the 748-998's "sitting on the bike" riding position opposed to the 749/999's "sitting in the bike" riding position. After the session, I came back in and moved the controls around so I could manipulate them better and went right back out on the track.

Over 3-4 laps, I started upping the pace a little per lap to see what the bike was going to do to or for me. I was cruising around in the 26s (at Grattan) just hanging out and familiarizing myself with the idiosyncrasies of the bike when a couple of guys with yellow plates came by, so I figured it was time to step it up a bit. I followed these two guys around for another two laps noting what the bike was and was not doing, which wasn't much. The only two things that stood out were that the brakes were violently grabby and needed a less aggressive pad with less bite and that it was almost impossible to get on the gas smoothly and not upset the chassis. The bike has a ton of torque and, unfortunately, it hits like a ton of bricks. To truly go fast, the throttle bodies would need to be set up real good and maybe some cam timing changes to push the power up further in the rev range. The power was hitting hard enough on the edge of the tire to either make it spin or it would put an input into the chassis that was a bit uncomfortable. As far as suspension impressions go, I really didn't have any. It felt like...well, a set up Duck. My lap timer only recorded the first couple of laps, so I don't know what I was doing out there, but I didn't care much either, I was just shaking the bike down.

Once back in the pits, I played around with the handlebar placement a bit and took some preload and compression out of the forks because I wasn't using them all yet. I threw the warmers on at 175 deg and hung out and told lies about how fast I was for 20 minutes or so while waiting for the next session. I knew the next session was going to be the one where I was most likely to do my fastest laps. I was all warmed up but not tired, and the tires had the right amount of time on them. I set the tire pressures hot before I went out on the track for the next session and started to get focused on doing a few fast laps. I managed to get on the track first and put my head down right away. The tires were perfect, so it was a good time to see what I could get out of the bike. I had totally clear track for the first flying lap which was a 25.2. Not bad, I wasn't riding very hard yet. I didn't have anyone hold me up on the next lap either and knocked down a 23.7. I was pleasantly surprised, I wasn't even riding that hard and the "no crashing light" was on bright. Remember, not my bike. After seeing the 23.7, I wanted a 22, which would be a lot more than I expected for the first time out on the bike. I attacked the next lap hard but got held up through 6-7-8 by the track day guys and only managed a 24.9 on that lap. As I was crossing the line at start/finish I could see there was no one on the track between me and the jump, which meant, unless someone got on at 5, I would have another clear lap. So I tried to relax, hit all my marks, and put in a nice smooth lap. Well, it paid off. That lap was a 22.2, which is very good for me at a track day and taking into account I was riding someone else's bike. I rarely get my lap times down that far even during race practice. Low 24s are the norm. There's a switch in me somewhere that only turns on when the green flag drops. I always go a lot faster during races than during practice.

But you're not reading this to know what kind of laps I rode. You want to know how the bike works. And the answer to that is "great." It feels just like it should, a well set up duck with a high seat height. Despite having a 100mm of trail, it still turned very fast, and I was still running the short OEM bars. A wide set of aftermarket clip-ons would reduce the bar effort even more. The bike didn't wear me out at all, which was a big change from when I first rode it. And I never felt like I was even pushing that hard. I know there's more time in the bike, too. If I spent a couple of days just tuning, I know I could make it even easier to ride. The biggest things I wanted to address had nothing to do with the suspension though. It needed some less aggressive brake pads, and it needed some tuning to smooth out the throttle application on the side of the tire. And a short throw throttle would help out tremendously. It felt like I twisted it around twice to get it to WOT.

Since the first test I rode/tested with the bike at two more track days to rack up some seat time and make sure that I was 100% satisfied. Of course I goofed around with settings between every session to see what would happen but aside from a little nip here, and a little tuck there I don't feel the need to make any changes to the bike.

The forks are the stock Ohlins except I'm running .925kg fork springs and they've been rebuilt/had an oil change.

The shock is the 46mm Ohlins that came stock on it, and I updated the valving package to current specs. I'm running a 7kg shock spring.
I'm running the stock shock link/rocker arm.
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