Owning a Ducati is a terrible experience. That’s why it’s so special.
Experience may not be the right word; lifestyle might be a better fit. A Japanese motorcycle, on one hand, affords the owner of drama-less starts and carefree rides that can stick to a schedule. There are no worrisome noises originating from in and around the engine, and you can essentially be the same person you were before owning the bike.
A Ducati, on the other hand, will throw your daily schedule and expectations out the window and replace them with its own. The bike is a moving work of art but it’s also a prissy attention seeker. It will soon teach you why you are the only “Duc” rider in the area.
Now, to clarify, I’m not speaking about the new-ish Ducatis that are being cranked out of Bologna in droves. No – it appears that those have gone through a mechanical testing regimen that rivals those of the Japanese competition. Overall, these are well-wearing machines that predominantly run like clockwork. The troublemaker Ducatis I’m referring to are the now-affordable and forever gorgeous 916 era bikes. This includes the 916, 748, 996, and in some cases the 998. These are the machines that really nailed down the high-maintenance and expensive-to-operate Italian motorcycle mentality. But oh, are they ever beautiful.
I have owned a 2001 Ducati 996 Biposto for about a year now. In that time frame I have put 1,100 miles on the bike and spent around $700 in maintenance-related repairs. Yes that’s right; almost 64 cents a mile. That sounds bad. Ok it is bad. Keep in mind that I do all of my own mechanic work, so that dollar amount is strictly the parts cost. I’d be in significantly deeper hole had I taken the bike to a reputable mechanic to be worked on.
The truth is that $700 is the bottom end of the “expected” maintenance expense for a Ducati of this age. If you buy a Ducati from this era you have to assume the responsibility of changing the timing belts and adjusting the valves at a minimum. Unless of course, in a rare turn of events, you have paid book value for the bike and the previous owner has meticulous maintenance records and has also recently had all of this work performed. Again, that is a very uncommon scenario. Usually when these beauties come up for sale the seller just wants them out of their life, no strings attached.
Even so, those maintenance items still don’t add up to $700 in parts. No, there happens to be a lesser-known and fairly expensive maintenance issue that can creep up on you. An issue that most manufacturers would consider a serious defect. An issue that only presents itself when you go to perform a routine oil change. An issue that will make your heart sink.
Flaking rocker arms.
Add another point under the column Things That Honda Motorcycle Owners Do Not Have to Worry About.
School Is In Session
Ah, the Desmoquattro engine. Residing within this mechanical ball of frustration is the desmodromic valve train which is a staple of Ducati engines. There are no springs that pin the valves closed like in a conventional engine. Instead, there is an opening rocker arm and a closing rocker arm for each valve. The camshaft has two opposing lobes for each valve, one operates the closing rocker, and the other lobe operates the opening rocker. Getting into the details of how this system operates is a story in itself, so the picture below will have to suffice for the scope of this post.
Basically, this means there are 16 rocker arms because there are 8 valves in this engine. Each of those rockers has chrome plating in the locations that ride on the camshaft. Over time, this chrome plating begins to let go in little bits and pieces. Many a forum thesis has been written on the topic of why this happens. Some blame it on inferior chrome plating done by a third party company that Ducati contracted with at the time. Others say it’s due to not providing sufficient time for oil to get to the cylinder head on a cold start. Others attribute it to a dissimilar material hardness between the camshaft and the chrome plating. Regardless of its origins, it is an issue that can’t be ignored.
There are a few issues that can to develop if you do not replace flaking rockers:
- Small metal flakes clog the filters and oil galleries leading to horrific engine death.
- Valve tolerances will loosen significantly causing rough running.
- Camshafts will begin to wear due to degrading and uneven rocker arm surface.
- General chaos and regret that an Italian machine typically provides will commence.
When you drain the oil and pull out the primary mesh filter screen you will know immediately if you have flaking rockers. Unless you recall that you intentionally added glitter flake to the oil for that extra ‘bling’ many riders go for these days, these shiny slivers mean that the rocker arms in the cylinder heads are starting to let go. Out of the 16 rocker arms in the engine, all you know at this point is that at least one needs replaced. At about $65 a pop for re-manufactured better-than-new rockers, you cross your fingers and hope for the best.
When this inevitably happened to me, there was only one logical course of action: Strip it down and brace for the financial unknown.
Taking it Apart is Easy…
Getting down to the innards of one of these bikes isn’t too difficult once you’ve done it a few times, which you will have done, if you end up owning one. Everything is held in place with the minimum number of fasteners to keep pieces in place while still providing the right amount of fragility you would expect from an Italian vehicle. For example, these two plastic pins, which are held together with a rubber strand, are practically all that secures the tail fairing to the frame. How innovative!
After yanking out the gas tank, air box, fairings, and battery, you eventually will expose the timing belts of the engine and the accompanying rat’s nest of factory wiring.
With the timing belts removed, it’s time to start digging into the valve train.
Desmoquattro engines have cute little valve covers that provide you with borderline-insufficient access to see or feel what is going on inside of the cylinder head. Thankfully Ducati remedied this with Testastretta engine found in the 998 and later machines by fitting valve covers that, when removed, actually provide a complete view of the valve train so that a normal human being can work on it. Mechanical convenience seems to evolve at a geologic pace at Ducati, so if you’re a 916/748/996 owner, you’ll have to learn to see with your fingers. Here is the exhaust cam cover on the forward cylinder removed. You can see the camshaft and the opening and closing rockers for this pair of exhaust valves. There is a bunch of stuff going on in a fairly small amount of space.
With the camshaft and opening rockers removed, you can now see the closing rockers and inspect their chrome plating. These rockers, while worn, are still in serviceable shape.
The Culprits
Since this is an abridged version of the rocker replacement, I’m just going to skip ahead to the carnage.
In all, I found four opening rockers that had chrome plating chipped away. The camshaft lobes were all in good condition and all closing rockers were serviceable. Here is a close up of some of the rocker flaking.
Upon close inspection you can see that chunks are missing from the opening rockers. Knowing the extent of the damage, I could now order the four new rockers I needed. Within a few days of ordering, the new rockers showed up and it was time to get them installed.
Here’s one of the new opening rockers going in.
More than halfway through the project and I find myself burning that midnight oil. The longer a project is in pieces, the easier it becomes to forget how it goes back together. Sometimes it’s best to sacrifice some sleep to get it done.
Making Some Adjustments
Unfortunately you can’t simply slam new rockers back into the engine and call it a day. Because you are installing new chunks of metal, they will have not worn like the ones you have just removed. This means that valve clearances will most likely be way off on the valves that were fitted with new rockers. Due to this engine having two rockers per valve, it means that you have two shims per valve to check the clearance on.
This can be a somewhat time consuming process, especially the first time you go through it. It isn’t necessarily difficult but it does require a bit of precision as you are measuring the difference between hundredths of millimeters. You will probably discover multiple valves needing adjustment after you have taken your valve shim clearance measurements. To make these shim adjustments, out must come the camshaft and opening rockers.
Opening shims are really simple to replace. You just take them right off the top of the valve stem and plop a new one back on. When doing the valves on a Ducati, you just pray that the closer shims don’t need changed.
However, this is reality, and usually a few closer shims need changed out too. Removing these shims requires a little finesse paying careful attention to not lose small pieces. With the opening shim removed, you must depress the closing rocker downward to expose two microscopic half rings that secure the closer shim to the valve itself.
Here’s what it looks like when the closer shim is removed. You can see the channels in the valve stem that the half rings slot into. At this stage, the valve is completely free-hanging in the cylinder head. If the piston for the cylinder that you are working on is not at the top of its stroke, the valve will fall into the cylinder. Talk about an instant work multiplier! Top tip: Don’t let the valve drop into the cylinder. Make sure the piston is at TDC.
With the new closer shim fitted onto the valve and the half rings nestled back into their grove, you can now put the opener shim back on top. One valve done, seven more to go!
Before I knew it, it was morning and all rockers and camshafts were back in place, valves were adjusted and valve covers were refitted. The strenuous neck craning and eyeball squinting was finally over.
Next, it was time to throw on some new timing belts and tension them up to spec.
Seizing the Moment
When you have everything disassembled like this, you have to take the opportunity to replace parts that are known to go out without warning. One of the many Achilles heels on these bikes is the coolant reservoir. The plastic will degrade, become brittle, and then spring a leak from a hairline crack when you least expect it. Listing at less than $50, it’s a good idea to fit a new one while you’re in there.
Ten minutes later and the new reservoir is nestled back into its otherwise completely inaccessible recess within the frame.
Another while-you’re-at-it item to fix is the electrical connector for the voltage rectifier. It tends to melt over time which could potentially lead to fiery death. I’m surprised this bike was able to keep a charge with the connector looking like it did. It’s cheap and easy insurance to replace it now.
Purchase the rectifier connector kit here: https://amzn.to/38fTVJC
After the connectors were changed out, I then fitted the timing belt covers and routed the wiring harness.
Next it’s time fill up the cooling system and change the oil – the job is nearly complete.
Finally we’re all buttoned up and ready to embrace another 50 trouble free miles! Hooray!
It’s Worth It in the End
The engine sounded like it had more bark and a crisper throttle response when starting the bike for the first time after the rocker replacement and valve adjustment. I was probably just searching for some sort of justification regarding the two weeks and $700 I had just spent fixing it. Who knows, maybe it ran no differently than before. All that really matters is that now I can rest assured that it is good to go for a few thousand more miles.
Adopting a 916-era Ducati can certainly get off to a rough start if you aren’t prepared for the quirks and nuances that are bound to be present. A little hands-on mechanic work can go a long way in keeping the maintenance costs down and making the ownership experience a more enjoyable one.
I’ve found the character that these bikes exude makes up for their occasional inconveniences. In the end, you’ll thoroughly enjoy having one around. Just make sure you also have a Honda.
