Like this? https://motowheels.com/i-8328068-corse-dynamics-ducati-stainless-steel-case-saver-chain-guard.html
That looks right. Although, the part I was referring to was a replacement alternator cover that I got off eBay.
Finally got the parts to start working on the bike and found horrors. The crack is inside the case we're the slave is bolting up. What would you do to solve this? JB weld? Welding? I can't weld here so then it's engine out.
That crack appears to be where the alternator case bolts to the crank case - maybe the bolt that is hidden behind the slave? If that’s the case (excuse pun) then it needs to be properly repaired as it is needed to make sure the alternator case is evenly applying pressure to the mating face of the crank cases. If that cannot be correctly torqued up then there will be a large span between the adjacent attachments and you will likely have a leak. I think the case needs proper welding and a new thread/helicoil. Make sure that the mating faces are super flat after welding. What a pain in the butt!
You're right. It's for the alternator cover behind the salve. Total crap. I need to find a welder. Thanks for quick response.
I had my wife's Monster crankcase repaired (after she was knocked off her bike) where the sidestand bracket bolts to the crankcase, which caused a small crack. It's held up remarkably well and no leaks, plus you would need to look very closely to even spot the repair. I am not sure how easy yours will be to weld but if you were to remove the alternator it might allow the welder enough room to work on the damaged area without removing the engine, then you'd need to get a helicoil fitted. My only concern with that is that since the crack runs through the thread to the outside of the casting, it might be the case that they'll need to plug weld the hole and drill it out and retap it. Not sure if it's a blind hole or not. If not then the only other complication would be the risk of any swarf entering the engine when they drill and retap it. It would at least mean you wouldn't need a helicoil As RickyX said, the tricky part however, will be ensuring the mating surface is flat afterwards, which will be difficult with the engine in situ, as ideally you would want any excess weld milled down to the existing/surrounding level for a really accurate finish and to ensure a good oil seal. The worst case scenario would be to source a secondhand matching crankcase pair, but I appreciate that is a LOT more involved and expensive, though there are plenty of skilled specialists I or others could recommend, who would be able to disassemble the engine and swap out the internals, for a lot less than a dealer would charge you Saying all this however, I have seen people do wonders with some ingenuity and the right kit/tools, so fingers crossed you won't need to go to those extremes.
Thanks for the reply. I've been talking to a few different welders. All but one said no, won't touch it. My biggest concern with welding is that you risk warping or destroying seal. But maybe I'm exaggerating that risk? Maybe i should give jb weld a try after all. Thinking about drilling at the end to stop the crack, creating a valley which i then fill with jb weld. Since it's not cracked in the middle i think there is a very small risk of the pice coming undone a then a oil leak is the worse think that could happen. Though it would make welding later harder.
How far does the thread go beyond the crack? If there is plenty of thread past the end of the crack then JB Weld might be enough but if the thread ends at the base of the crack then as soon as you try to tighten the bolt down it will crack it open again. Fill with weld, drill and retap is the best solution really.
There is plenty pass the crack. This is one of the short bolts for the cover which should be tourqed to 10 NM.
That’s not very tight then, if it was me and there is plenty of good thread left as you say then I’d give the JB a go. If it fails then you can still clean it off and get it welded. Just make sure you get it spotlessly clean before you use the JB Weld.
Another thing. How would you guys go about doing the jb weld? Would you like i previously wrote drill a hole at the end and cut a valley in the crack and fill with jb weld or just get as much as possible in the crack, squeeze together and lay it out on top?
Use something like a spray on brake cleaner to clean the crack If you heat the JB Weld once mixed with a hair dryer it will get very thin and flowable (mix a small amount and try it to see what I mean) Could you drive a small screwdriver into the flat face below the thread to open the crack slightly-apply the heated JB Weld and add more heat to get it to flow into the crack then gently using some lock plyers put one side in the large hole and the other side on the outside of the cracked piece and gently squeeze and hold together. Then gently run a bolt backward and forwards through the threaded hole in case the JB Weld flowed through in to the thread
First jb weld was a total failure. Tried to heat it so it would go in to the crack. Which it did, about 0.1 mm. Next i tried to open it with a screwdriver resulting in the pice breaking off. Now the second time it holds 10 nm no problem. Let's hope it holds over time. What do you guys think of this "professional" work? Thinking heat cycles and vibrations might be a problem. Otherwise I can't see that it would be under heavy load other than the 10 nm. After the picture was taken i sanded it down a bit and put a new light coat on extending the repair a little.
