Can anyone offer up any advice. Van recently hit my wife side on and on inspection, amongst the other damage, the sidestand bracket forward mounting lug on the crankcase has been cracked and bolt was bent when removed. Local Ducati specialist says with confidence that an insert can be used but the lower part of the lug has cracked and been pushed inwards and down. Surely if just using an insert, won't the rear surface of the sidestand bracket only be butting up against / be in contact with the top half face of the lug/ Is it not likely to need welding? If so can this be done in situ or is it an engine out job? Only had the engine out two months ago for a full rebuild after it threw a big end bearing.
Weld and insert in-situ, I reckon - but it is only a chance it will be OK. That crack at bottom left, doesn't look good to me.
You can't use an insert, as there is no support for it, due to the boss being split. It will just force it open even more.
Thats what I thought but then again the specialist has thirty years of Ducati experience and is confident it will work. I trust him implicitly but my concern is the hairline crack leading from the boss back down the side to the face of the crankcase. There also a smaller one on the other side.
you can use an insert but thats only half the story, to me I'm looking at the crack at the base of the boss and the web. You don't know how far that forward crack has propagated. It's a potential stress and failure point if left unattended.. Those bores don't go very deep and it'll always be a point of flexion when the weight of the bike gets put on the stand. Find a decent fabricator aerospace preferably and he'll be able to weld that all up for a few beer tokens in about half an hour
Looks like the other has already had an insert. Best to clear all the paint away from the area and get it crack tested with dye. You could get it welded up and re-tapped, but would need to get the mounting face machined level to match the other boss. I would look to cut it off flush and weld a complete new boss to the flat case, however, I suspect the thread goes deeper than just the thickness of the boss.
Since I have seen some residual oil leaking from the area (engine has already been drained) and the tapped hole is blind into the crankcase, I'm fearing its compromised the casing. I think I will get my local specialist to take another look Hmm sounds like a more permanent solution to me. The thread does go deeper than the boss. However your suggestion gives me that sinking feeling that this will need the engine to come out and at worst the cases split to get the part repaired and machined.
the top of the boss isn't compromised, which is the good part as you'll have a datum to work from. If you look at your two photos its the bottom of the boss. At the front it's chipped away, at the back it's cracked down onto the main case. Your specialist will say new cases 99%, i'll wager. Get a fabby to look at it it might be that an insert is put in and them filler rod is built up around it, and the crack repaired. You won't know how that crack has propagated until you strip back the paint locally in that area, which you'd need to do for the welder anyway. I had a similar situation with a gsxr1100 which I bought for the price of the van hire to get it to me.. the chain strike had wiped out the water pump and it's webs I cleaned up the area And tame ex F1 fabricator welded up what was left of the web and rebuilt the missing tower. (I might put a thread up if anyone is interested... well, it ends in an i). I worked on the principle that if I needed a new engine case it was engine out and splitting the cases. IF this worked I wouldn't have to split the cases or take it out of the bike (which I did as he recently had an operation on his knee and I wasn't about to have him kneeling down). win. If it didn't work, I was back to option one + a few quid lighter. Worth a try I think as it was a few quid vs new(ebay) case, gaskets, strip down and rebuild cost. Worth considering if budget is a thing.
The cracking looks localised to me, I think you’re specialist is right and you could just about get away with an insert due to the thread extending into the casing beyond the depth of the boss, but having it welded and filed/linished smooth (no need for machining) and repainted would make a better job of it.
The cracking looks localised to me, I think you’re specialist is right and you could just about get away with an insert due to the thread extending into the casing beyond the depth of the boss, but having it welded and filed/linished smooth (no need for machining) and repainted would make a better job of it.
Is that a crack above and between the holes? To have a chance of successfully welding that you really need the cases splitting IMO. Plus you need to establish how deep the crack at the left goes as it may have weakened the area to the point where the case will break away?
Another way to do it could be to remove the broken lug completely back to the casing hopefully removing all the cracking out in the lug. Make up a spacer the same size as the broken lug and have this welded in place. Drill it out and put an insert in. Have both the holes got inserts in already? That will make it awkward if the top of the insert has broken off.
We've owned the bike from new so I don't know why it would have an insert in it unless it was put there without my knowledge. Bikes never been dropped until.the accident recently. I think this could go one of two ways. Put an insert in and it fails or remove the boss and weld on a new spacer and drill and tap it which seems a better solution. The cracking that leads down to the crankcase itself is what worries me
Sorry did not read them all. Reason it looks like there is a insert because on the undamaged lug you can see the darker material round the thread which looks like a steel insert. If the other lug has the same, it means the top of it has broken out and may lead to complications.
I appreciate that this was not on a 620 crankcase, ( it was on a 900 SS) but I have got by with a temporary solution making up what I call a shadow plate. This would rely on using an adjacent redundant boss (I believe you might have one? see pic) to attach the plate to for additional strengthening. The remaining good boss would be used as normal possibly with a longer screw/bolt (or as long as possible anyway) and the damaged boss would need modifying to make space for a steel nut which would be located (preferably welded) behind the shadow plate. I think I used something like 1/8th inch gauge plate or similar which of course means the side stand is that much further away from the crankcase but it certainly didn’t make any difference when fitted and used.
Thanks for all the suggestions chaps. I have sent the pictures to the local specialist to see if they still feel an insert is a viable option. Looking at it up close and personal I'm concerned that this will not be strong enough, not withstanding that the insert will not have a complete hole in which to reside and that given the original OEM tapped hole is a blind hole into the casting and I have seen oil leaking from it (or maybe it was from the cracks on the sides of the boss), that the case has been compromised in which case it is either going to have to be welded and that means engine out and cases split and casting stripped, (since the heat generated when welding will cremate any adjacent oil seals and o-rings anyway) or engine out and they can effect a repair without splitting the cases. I seriously have to consider after having only just paid for a costly engine rebuild less than three months ago after the big end bearings went pop, if this is now a viable option. My wife does not want to part with the bike but if I do end up having the engine rebuilt it's going to cost at least another 500 quid and the potential of a replacement crankcase on top of that if this one cannot be salvaged and finally getting the secondhand one or the existing repaired one painted to match the RH casing. Decisions, decisions!! It s a bugger as the rest of the damage to the bike is mostly superficial, broken front break lever, footrest hangar bent gear lever and bar ends plus a few parts that will need repainting from scuffs and scratches which would have been quick and easy to remove and replace. I hae already ordered and paid for most of those needed when I first saw the bike but only discovered the damaged boss after I removed the bent sidestand and then removed the bracket. The front mounting bolt was severely bent which has ripped out the threads and where the van hit her leg and the LH side of the bike probably collected the stand as well as the bike actually fell over onto its right side in the road which is where most of the obvious damage was, but he hit her hard enough that her leg fractured the LH footrest hangar into three pieces which is probably the same point at which her ankle bone broke. Insurance is in place to repair the bike which they have agreed to but not sure it will cover the cost of repairs to the crankcase as well, since this subsequently came to my attention, in which case they may pay for the remaining parts and I'll have to stump up for the repairs to the damaged crankcase/engine rebuild again. Bugger!
If you can establish that the forward hole is definitely not leaking then a shadow plate will be your best option but from 10mm or 13mm alloy plate rather than steel. Some years back I had a 900ss which had suffered similar damage after an off by the previous owner. In this case half of the boss was completely broken off. It was "repaired" by the use of 13mm alloy shadow plate. The plate was attached to the spare threaded hole at the rear and with a longer bolt through the stand lug and the plate into the next threaded hole. The forward mounting screw for the stand lug was screwed into a suitably threaded hole at the front of the shadow plate, so the forward broken boss was no longer used. With this arrangement there would be no load on the broken boss so the crack would be unlikely to propagate and if there is any oil leakage it should be possible to fill the crack with JB Weld to stop it. It is certainly worth a try before writing the engine off and the 13mm plate had no effect on the operation of the stand and was almost unnoticeable on the bike.
