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Anyone had similar experiences with this?

The flywheel nut is still secure and shaft still in the flywheel but completely detached!

Felt small vibration, steadily increasing for a few miles then pulled over and the bike stalled. I.e. crankshaft snapped
 

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Bon Vivant
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A couple of years ago I went to a Ducati demo day at the local dealership. The guy who was managing the ride spoke to our group before we set out and one of the things he stressed was not to "lug" a ducati engine. Riding at low RPMs, he went on to explain, is very hard on the crank shaft and can ultimately cause damage. Since then I've found quite few Multi owners try to ride at super low RPMs - under 3000 for any extended period is too low and low RPMs in higher gears are even more stressful on the engine. I have a friend who is an older gent who constantly switches up to 6th gear for cruising even when were are going 40 or 45 MPH. He complained to me that the muti has no power. He's riding this thing around at 2000RPM! I tried to explain to him but he laughed and said something about his superior fuel mileage... This guys has owned bikes his entire life and has 50+ years of experience.

I'm not saying the OP or any others with crank problems are guilty of this but it is something that we should all be aware of.
 

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I'm one of the folks that think that some worry too much about low rpm operation (typically those who come from the superbike end of the rider spectrum)... but even I don't run the bike under 3k with any load at all. From 3-4k the rider needs to be careful to manage engine load (gentle acceleration is possible but the Multi isn't a GS... you won't get smooth power from 3k-3.5k and it's only a bit better from 3.5k-4k). 3500 is perfectly fine for cruising through a town's 30mph zone at a steady speed. It's also fine for cruising along a country lane at 45-50mph (or whatever 3500 amounts to in 6th). But... if you want to accelerate away you need to shift down because 3500 under load will cause a lot of drivetrain strain due to having two big can's with very short strokes.

As a general rule... minimize the engine vibration and you'll be fine. From 3-4k engine vibration is a pretty noticeable thump thump thump... don't do that. It's not lugging... but it's probably still not good for your motor and drivetrain. from 2-3k you probably WILL get lugging... and that's REALLY bad.

Getting 50mpg is great and you CAN get 50mpg safely with the Multi (it's easy... just keep your wrist un-twisted - IF YOU CAN... BWAHAHAHa)... but causing $5k-$10k in damage to your bike to save a few bucks in gas... probably not super smart.
 

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.... He's riding this thing around at 2000RPM! I tried to explain to him but he laughed and said something about his superior fuel mileage... This guys has owned bikes his entire life and has 50+ years of experience.
Sounds more like he has one year of experience repeated fifty times over.
 

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My ‘13 broke exactly the same way as your at 12,700mi.

Went thru my local dealer to bring it to Ducati’s attention. They in the end offered me $4000 towards parts but the entire rebuild was quoted at $8800. I found a used monster 1200 engine with 1900miles on it for about $2000. Decided to use that engine but the cylinder heads are vastly different so will use my stock mts heads. The m1200 has higher compression so to deal with that my plan is to use a set of 1098 cams. Should be a little bit more lively, cost less than the dealers full rebuild and I get to build it how I want to.

Good luck!
 

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Another contributor to these failures, in my opinion, is the fact that the mts flywheel is twice as heavy as the 1198. Ben Fox mentioned that these cranks do a little better with a lighter flywheel...

Also had one of the metallurgists look at the fracture and he said it was classic torsional fatigue. I took a closer look at it and there were some questionable features. Unfortunately they would require more work to determine if they were defects or not...
 

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People, especially new to Ducati riders, are constantly questioning why their bike doesn’t run smoothly below 3500 rpm. My theory has always been to make sure the bike is in good tune first, then if it still vibrates at a certain rpm, it’s trying to tell you something. It’s not happy, it doesn’t like it, don’t do this. Even Harley’s have this rpm range, and shouldn’t be lugged. One of the main things to consider is adequate oil flow on some bikes. Most motorcycle engines are not designed to run at low rpm’s.
Do you think it might help against crankshaft breakage to switch to a lighter flywheel ? It seems plausible.
 

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Even Harley’s have this rpm range, and shouldn’t be lugged.
This was pointed out to me very early on in my HD ownership years. It's particularly relevant to their crankpin arrangement - both rods sharing the same bearing point on the crankshaft. I then started observing all the people that deliberately lowered their idles to get that slow thumping sound - sounds great, but inside my head always sounded like a crankshaft and bearings being tortured!
 

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Some Diavels have the same issue, there is lots of conjecture about why it happens, what's interesting though is when they went to the Gen2 the flywheel was a little lighter and the crank was a little more substantial.

I took that as a suggestion that maybe i should take the std flywheel off mine so i bought a std 1098 flywheel and put that on in it's place, the std Diavel flywheel weighs nearly 4kg! the std 1098 one weights just a shade over 2.

I know why they instal such a heavy flywheel but really, the 1098 one hasn't made much difference in how it rides, i'm happy i have changed it, will it save my crank? i don't know, but not all of them break, at least i've done what i can....

Lugging the engine is a possibility, also when the cases are assembled they measure crank deflection and there have been plenty of threads on bearing failures etc from too tight an engine, i wonder if not warming them properly could contribute too?
 

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Even Harley’s have this rpm range, and shouldn’t be lugged.
My stepdad spent piles of money on his FXRT to get more power. Jerry Branch welded up and machined heads, Supertrapp exhausts full system, aftermarket carb, cams, the lot. And even after doing all of that, he still couldn't keep up with my stone stock FXRS. I tried to tell him many times that the problem was how he short shifted the livin' hell out of his engine. He would ride it in far too low rpm ranges. All of that money was wasted on his 1950s riding style.

Many riders act like they're on a John Deer tractor or something ... be them Ducati or Harley riders.
 

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Some Diavels have the same issue, there is lots of conjecture about why it happens, what's interesting though is when they went to the Gen2 the flywheel was a little lighter and the crank was a little more substantial.

I took that as a suggestion that maybe i should take the std flywheel off mine so i bought a std 1098 flywheel and put that on in it's place, the std Diavel flywheel weighs nearly 4kg! the std 1098 one weights just a shade over 2.

I know why they instal such a heavy flywheel but really, the 1098 one hasn't made much difference in how it rides, i'm happy i have changed it, will it save my crank? i don't know, but not all of them break, at least i've done what i can....

Lugging the engine is a possibility, also when the cases are assembled they measure crank deflection and there have been plenty of threads on bearing failures etc from too tight an engine, i wonder if not warming them properly could contribute too?
Good to know on the vibes with the lighter FW. Did you have to machine a spacer for the rotor with the 1098 unit? I'm planning to run the monster 1200 FW as its 4.9lb vs the MTS's 9.6lb but the monster flywheel is ~0.4 inches skinnier so will have to space the rotor off the flywheel. As i'm typing this, i wonder if i couldn't space the stator off the case...

Also on lugging, it's tough not to lug these things when highway cruise speeds are at like 2,000rpm. Wish the gearbox were tighter and 70-80mph landed at a "safe" rpm...
 

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So live, yes you just need to machine a spacer on the lathe to run a lightened superbike flywheel. I have a Nicholas from an 1198 on my MTS...beware it will stall much easier, I eventually tuned that out with tuneboy settings....and 1098 cams work well with MTS.... I have a set in mine....midrange sufferers very noticeably. I did however bring the compression ratio up with 1198 sbk pistons.
 

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The first Ducati I test drove was an ST3... and thinking it was a V-twin... well... L-twin... it was supposed to have bottom-end torque, right? I'm riding this thing and it's just falling on itself... and really had me scratching my head.

Fast forward to 2016, when I bought my 796... same-same. I figured out real quickly that I had to keep it above 4000rpm to even keep it running... which was OK, but not something I was used to. Slip-ons helped the low-end response, and regearing really helped rideability... but 4000+ is really it's happy place, and I know that now.... and that's where it stays.
 

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The first Ducati I test drove was an ST3... and thinking it was a V-twin... well... L-twin... it was supposed to have bottom-end torque, right? I'm riding this thing and it's just falling on itself... and really had me scratching my head.

Fast forward to 2016, when I bought my 796... same-same. I figured out real quickly that I had to keep it above 4000rpm to even keep it running... which was OK, but not something I was used to. Slip-ons helped the low-end response, and regearing really helped rideability... but 4000+ is really it's happy place, and I know that now.... and that's where it stays.
Power from 4000K plus is bottom end torque for a Ducati
 
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