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Discussion Starter #1
Well, looks like it's my time for the cracked engine case experience...



Not sure how long it's been like this, just noticed it when I had the bike stripped down for valve check. I didn't know this was a known issue so I hadn't been scrutinizing my mount locations. I just happened to be shining a flashlight around and saw the crack :frown2:

Looks like it's time to pull the motor and haul it to a welder. I'll also do some upgraded engine bolts while I'm at it like this thread: http://www.ducati.ms/forums/40-sport-touring/710690-broken-engine-bolt-worth-checking-yours-2.html

I'm supposed to be heading out next weekend for a 1000 mile moto camping tour of some twisties. There's no way I can pull the motor, get it welded, and then back in and running by then. Do you think I'm flirting with disaster by riding it another 1k miles before getting this fixed up?
 

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I hate that for you VA. Personally, I wouldn't ride it like that since the motor is a stress member. IF your trip is with a group, I'd look into getting a rental.

Good luck,
Scott L.
 

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It's not going to get better by riding it that way.

It is repairable as is. Let it get worse (especially if a chunk or two disappears), and it gets a lot more complex and expensive to repair.

Thank your lucky stars that you found it at this point, and fix it now.
 

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That's no good! I don't remember anyone reporting a broken front mount. All the topics I've read have been the rear mounts. Did the bolt break too?
 

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Discussion Starter #6
I
It's not going to get better by riding it that way.

It is repairable as is. Let it get worse (especially if a chunk or two disappears), and it gets a lot more complex and expensive to repair.

Thank your lucky stars that you found it at this point, and fix it now.
I didn't think about the complexity of the repair if that broken chunk disappeared. That's it, time to shelve it until I can pull the motor and get it to a welder.

This is pushing me to pick up my brother's KLR for a backup bike. Gotta hit him up for the family discount

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Discussion Starter #7
That's no good! I don't remember anyone reporting a broken front mount. All the topics I've read have been the rear mounts. Did the bolt break too?
You know what, I didn't check that bolt when I put the fairing back on... I'm going to get replacement bolts either way. Not going to do all that work and use the same bolts.

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A missing chunk doesn't make it more difficult to repair, really. Just saying. That said, I'd find another mount for your ride.
 

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Thats similar to what mine looked like on my rear mount that cracked. I had caught mine early, so their was only one hairline crack. My rear bolt actually broke. After considering the pros and cons of drilling out the hole diameter in the case, I decided to drill to 12 mm, like the newer ST4's, after welding. So far, its been a good decision, as I have had no issues after the welding and drilling.
 

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Discussion Starter #10
Thats similar to what mine looked like on my rear mount that cracked. I had caught mine early, so their was only one hairline crack. My rear bolt actually broke. After considering the pros and cons of drilling out the hole diameter in the case, I decided to drill to 12 mm, like the newer ST4's, after welding. So far, its been a good decision, as I have had no issues after the welding and drilling.
What year did they switch to the 12mm? Mine is a 2002.

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Discussion Starter #15
Haven't gotten a chance to start pulling the motor or check the bolt yet to see if it was broken or loose. I did get to do my weekend ride though. I was in the garage looking at my wife's Honda Rebel and thought "how bad could it be?". So I loaded up my camping gear, stashed some extra stuff on my buddy's Electra Glide and chewed up 650 miles this weekend - most of them twisties. Slightly less power than I'm used to and a really loose chassis, but you know what, I had a ton of fun! I think it was good to keep a little perspective on sometimes its about the ride, not what you're riding. That being said, I'm not sure I'll plan on riding a Rebel that far again... :)

A few distinct benefits of the weekend on the Rebel: 1 - never worried about cops :) 2 - cost me like $20 in gas for the whole weekend :grin2:



 

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I was in the garage looking at my wife's Honda Rebel and thought "how bad could it be?".
Well, now you know. :grin2::grin2::grin2:

I teach the MFS classes and we use Rebel 250's for the class. Most of the coaches hate them, but I have found a special place in my heart for them. They're great little bikes for what they are, but they're certainly not designed for anyone over 5' 8". :grin2:

Glad you had a good ride. Bummer it wasn't on the Duc.
 

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Discussion Starter #18
I shelved the Ducati for the summer as life got in the way and no time to mess with the motor. Ended up picking up a KLR from my brother for dirt cheap so that held me over the summer.

I've been missing the thrill of riding the Duc and decided last week it was time to pull the motor and see what the damage was. Surprisingly none of my mounting bolts were broken, I expected a broken one... A big chunk of material had broken off the case, not looking good! I ran it around to a few different places this past week trying to find someone who would /could weld and repair. The consensus was that the material where the break is located, is so porous that they were unsure it would ever be successful.

There's a local shop ran by a highly skilled and renowned drag bike builder, he said he could do it, but would only agree to it if I split the case and strip everything. And same story about the porous case - he said the material around the break was pretty trashy and there'd be no way he could guarantee it'd be successful. I've never split a case before, I might be dumb enough to try it but not sure if it's worth it at this point. Sounds like some work and probably a bunch of specialty tools! Am I crazy for even considering that?

What to do... what to do... hmmm



 

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Splitting the cases really isnt much of a chore, dont be afraid, it is just nuts and bolts that come apart and go back together in a certain order (piece o cake with a good service manual within reach). Since you already have the motor out of the frame, your half way there. Looks like you can source a set of cases in good condition for a couple hundred bucks on EBay if you are skeptical about welding the break. And whilst you are in there, it would be a great time to make sure everything is tip top shape. Winter is not too far away, and you know, the good Lord did create winter for motorcycle projects :smile2:
 

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I split the cases on a 1994 Monster 900 about 1 month after I bought it used. Only 4,000 miles and the left main bearing failed. I had done this many times on my dirt bikes, mainly 2 strokes, and I found it to be very similar to the Ducati. It really didnt require any special tools although I had to buy a big puller to get a gear off the right side that had locked tapers. I would think that if you bought another case, you would need to make sure the preload of the main bearings are set properly. To do this I borrowed a long depth micrometer from work and found a long straight piece of tool steel to measure the distance between the two bearing seats and then measured the distance between the two shoulders on the crank shaft. I placed each case on a table and placed the flat bar on the edge of the case. I drilled a hole in the flat bar and placed the depth micrometer through the hole and down to the counterbore for the bearing. I did this on both cases and was able to get the total distance between the two bearing counterbores. I had to borrow a caliper that was big enough to measure the distance on the crank. The preload is actually calculated by the interference (meaning the distance between the outer side of the two main bearings is larger than the space it goes into. You get the right interference by installing thin flat shims (washers).

Other than that, everything went together the opposite way of pulling it apart. There are alot of pieces, but I just labeled boxes and for each major component, like the gearbox. Put it all back together and everything worked well for many thousands of miles.

It looks like your case was defective (porous). My ST4 case that cracked was due to the broken mounting bolt and allowing the drive chain to put undo stress on the case. If you buy another case I am sure you can find someone who can figure out if it is porous (maybe xray it). Or maybe just by looking at it.
 
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