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I think my ‘93 SS has the dreaded frame crack. It’s really subtle though. I was really hoping to avoid this. Now I wonder how long it has been there. I’ve had the bike since 2001. My question, for those who have experienced this... is this a drop what you’re doing and fix this immediately kind of thing or put a mark next to it to see if it grows and keep an eye on it? I think I know the answer but wanted to get some second opinions. Thanks in advance.

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It's just going to get worse with neglect. One of those things you can't wish away, or pretend it's not there and it will go away. It doesn't look too bad just yet, you may be able to get away with having it repair welded and then installing a BBB Fab Frame Brace to stop any further cracking.

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Find yourself a good experienced tubing welder NOT a guy who CAN weld, they should be able to repair it once and for all. I have seen many repaired frames and once weld repaired I have not seen any repeat failures. I have seen some add gussets and yes the bolt on brace above, I have not seen any difference between additional bracing and no brace having problems after the repair so what ever method helps you sleep at night.
 

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Find yourself a good experienced tubing welder NOT a guy who CAN weld, they should be able to repair it once and for all. I have seen many repaired frames and once weld repaired I have not seen any repeat failures. I have seen some add gussets and yes the bolt on brace above, I have not seen any difference between additional bracing and no brace having problems after the repair so what ever method helps you sleep at night.
Listen to this man. He really knows his stuff, and has many years of full-blown experience specifically with Ducati motorcycles (as well as many others).
 

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Discussion Starter #5
Thanks. That’s what I was thinking. I was a little bit concerned that without a gusset the other side might eventually go. On the other hand it has been ok this long so I’ll focus on fixing the crack that is there.
 

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I had a tube welded in in the same spot as the removable brace posted by Rex. Besides the obvious problem of having to paint the frame afterwards, the main issue with the brace is that it made removing the OEM airbox a major pain in the ass. I had to split the airbox top and bottom halves to install or remove them, not the most fun job to do every time you do valves or touch the carbs etc.
It may be possible to have a different style brace welded in closer to the head tube to avoid this problem.

I solved it by installing FCRs with pod filters...
 

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Discussion Starter #7
Ducvet, any advice on how to find a good welder? Or what questions I can ask to know if I have found one? I found a mechanic who was at FerraccI for a lot of years and corrected a bunch of these back in the day by welding them. He sounded confident he could repair it but I’m not sure if he’s a welder or works with someone else. I’m planning on stopping in to see him soon and am trying to get my ducks in a row first. (I really wanted to say ducs in a row there). Thanks very much for the help.
 

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unusual for a 93 to crack. i would remove the bosses welded to the frame that the tank hold down bracket mounts to, to allow the frame to flex as it wants to, and make another bracket to hold the tank down. i welded a threaded boss to the back of the steering head (down lower) on my 93 frame to fix a tank hold down bracket.
 

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Ducvet, any advice on how to find a good welder? Or what questions I can ask to know if I have found one? I found a mechanic who was at FerraccI for a lot of years and corrected a bunch of these back in the day by welding them. He sounded confident he could repair it but I’m not sure if he’s a welder or works with someone else. I’m planning on stopping in to see him soon and am trying to get my ducks in a row first. (I really wanted to say ducs in a row there). Thanks very much for the help.
Any good welding shop or machine shop will do. I think what Member *ducvet meant when he said ~don't just let someone who knows how to weld~ do it is don't let a buddy with a welding machine in his garage do the job (y'know, your typical shade tree mechanic type). Any machine shop or welding shop that is more than familiar with welding on tubular space frames will be fine. Most shops like that depend on protecting their reputations by providing good work. That guy you know down the street with the welding machine in his garage has nothing to lose if he does a fuddup job on your motorcycle frame.

Now, I've spoken for *ducvet here, which was inappropriate of me. Just to get that said.

The fella you mentioned who "corrected a bunch of these" sounds like a great place to start.

Here's a thread in this forum about how one member dealt with the cracked frame issue:

LINK = https://www.ducati.ms/threads/forced-restoration-of-900ss-after-finding-crack-in-frame.472634/

Here's an example or two of cracked SS frame repairs I've dug up ... there may be some overkill going on ... but then again sometimes this stuff comes down to putting one's mind at ease over what may actually be necessary. There used to be a kit available that included pre-cut gusset(s) that were ready to weld into place to address this cracked SS frame thing ... I can't recall who offered it or if it is still available ... someone else here may know. I believe the 3rd and 4th images are of the kit gusset. Image #2 depicts the TIG process using custom fit bracing.

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I'd reckon TIG, MIG, or even oxy-acetylene brazing would work fine. Brazing allows the joint and surrounding area to flex a bit more, which can prevent the transfer of stress to other areas of the frame. Note that the BBB Fab frame brace (made in England) is brazed together, most likely for the very reason I pointed out ..... here's one more look at that ....

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It's also noteworthy that some of the more successful and famous motorcycle frames were (and still are) brazed together, most were made in England. It's a very good method of fabricating motorcycle frames as well as repairing them. I did a number of rear suspension modifications to motocross bikes using this method on bikes that were raced every Saturday night for years without failures.... circa 1974/75.

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(below ... not my work)

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I just wanted to point out that there is more than one "right way" to take care of this problem. A competent welder can apply pretty much any method. Good luck!!!


.
 

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Discussion Starter #10
Thanks Rex. That’s great info. i found references to a gusset kit from Nichols and a listing on their website but it looks like they are long out of stock. I’m going to look hard at moving the tank hold down - the crack origin is at its attachment weld which makes it very suspect.
 

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One thing to notice as you look at all these frame cracks : The frame often tends to crack, or crack again, just beyond the braced or welded area. It appears that bracing the frame moves the point of greatest stress but does not stop the frame from cracking. It appears the bolted on brace may even be a little better against re cracking because it supports the stressed area without being totally rigid .
When welding a crack in tubing it’s advisable to drill a hole at each end of the crack first to reduce the chance of the crack continuing after being welded. I can’t see any evidence that this was done in many of those samples of repaired cracked frames. This is crack repair 101.
 

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The only thing that really works is to make the whole bike out of carbon fiber, right , Combi ?
 

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One thing to notice as you look at all these frame cracks : The frame often tends to crack, or crack again, just beyond the braced or welded area. It appears that bracing the frame moves the point of greatest stress but does not stop the frame from cracking.
Which supports the notion of brazing rather than welding. A brazed joint (aka "bronze welding") is more flexible, and has less tendency to create a "hard edge" at the end of the welded area. It also spreads out the stress over a wider area, again less tendency to crack/break at the edge of the brazed area.

It appears the bolted on brace may even be a little better against re cracking because it supports the stressed area without being totally rigid.
.. and again, it's brazed rather than welded.

I'm not sure I agree with the practice of drilling a hole at the end of the crack prior to welding in every case. If that were required, it would also be required at every joint. If I recall, drilling the end of the crack was more useful when repairing cast iron failures, since cast iron is so brittle. Welding up cracked brittle metals can also make the crack "run" (continue cracking) as the damaged area is being welded, drilling a hole helps to stop the crack from "running" while welding. It should also be noted that when drilling a hole at the end of a crack, the hole should be drilled at least 1/8" past the visible end of the crack since cracks can continue well past the visible end. Drilling is also required in some situations to prevent "blow out" or "blow through" ... where hot/expanding gases can blow the puddle out near the end of the weld. The drilled hole allows those hot gases to escape without blowing out the puddle. Once the weld is complete and cooled a bit, filling the hole with a bit of weld finishes the job.

If I recall, end drilling of a crack depends a lot on what the base material is.
 

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Well the clamp on frame brace is what I did, My frame has no cracks or damage but I got the BBB Fabrications frame brace just as an extra insurance policy. and the nice thing is you can remove it in 2 min so you can R&R your airbox with no problems. My thought was --frames cracking are a known issue, --So if I can eliminate the issue before it happens why the hell not. --Now my bike is a 91 white frame bike and everyone I have talked to says they have never seen a white framed bike frame crack, this may be the case but still the frame brace cant hurt
 

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... better to have it and not need it, than to need it and not have it .... kinda like a 12ga under yer bed!
 

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Many ways to do the job right, tough part is knowing which ones leave you with the result you expect. I see no harm in extra gusseting but I personally do not believe it is necessary if the repair is welded properly. I do not believe the gussets are needed because the earlier frames with no gussets did not have the issue and the early 97 with the larger gusset still cracked. A bad weld process with a good design is as likely to fail as a bad design with a good weld process.


If you have an airport or aerospace manufacturers near by they often will have someone with the certifications and more importantly the certifications AND the practice welding to set you right up.

That is a beautiful frame above I wish I was that talented, maybe a new hobby in retirement.
 

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I think the tubing used on the frame was selected by the accounting department.
Also, the welding might have gotten the tubing too hot and weakened it.
Stosh, That frame looks fantastic.
 
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