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Discussion Starter · #1 ·
Does anyone else here think that the frame of the monster could be improved upon by adding a bar between the two engine mounts? I've seen a couple of engines with broken engine mounts and I think they break there because the frame flexes on impact in an accident.
 

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I think the whole frame itself can be improved in terms of a few additional crosstubes, tube sizing, better material (chromoly) and quality TIG welding. Then again I'm incredibly biased -- I build my own Ducati frames. (I use the old frames for shelves or artwork purposes only then)
 

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exertus said:
Does anyone else here think that the frame of the monster could be improved upon by adding a bar between the two engine mounts? I've seen a couple of engines with broken engine mounts and I think they break there because the frame flexes on impact in an accident.
Actually, the frame is too strong already, that's why it can transmit enough load to the cases to break 'em.

The trick is to make it weaker without losing stiffness, but not so weak that it cracks in normal service.

Superleggera said:
I think the whole frame itself can be improved in terms of a few additional crosstubes, tube sizing, better material (chromoly) and quality TIG welding. Then again I'm incredibly biased -- I build my own Ducati frames. (I use the old frames for shelves or artwork purposes only then)
You can make the frame lighter with chrome-moly, because it's stronger and thus you can use thinner walls.
But then you have to add crosstubes to get the stiffness back to where it was before, because you've got thinner walls.
Or you can use larger diameter tubing to get the stiffness back.
But the thinner walls make it harder to weld, and the larger tubes make it more difficult to get the joints accurate enough to weld.
Just drives the cost up....

Make no mistake, I do wish my frame was as pretty as what I've seen on a Brutale.
I probably would have paid the cost difference.
Other folks wouldn't...
 

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Does anyone else here think that the frame of the monster could be improved upon by adding a bar between the two engine mounts?
Original 888/851 frame had that.
The Nichol`s Engine Bolts are a good and simple improvement IMO.
 

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+1 on the Nichols mounts, but the motor damage comes from hard frontal impact & I'm not sure what could be done to make that better, short of better cases (which I've tried to get a group effort to undertake before - w/o success).
 

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O.K.,
I've seen several posts now extolling the virtues of the Nichols bolts, but haven't seen an explanation of WHY they are better than the stockers. I presume it's related to the big shoulders on the nuts... and perhaps how they install? Better material?

Also are these bolts beneficial to all Monsters or just the "older" frame styles with the "hoop"?
 

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Ducati frames are not chrome moly - only their racing frames.
The Nichols bolts (actually studs) fit the hole better, are slightly larger in diameter, and are made of better material. I use them on every bike I build.
I don't know much about the mounting bolts on the newer frames, but I think they are bigger than the older hoop style frames.
 

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Thanks Norm,
I just called Nichols to see what they had to say. They basically said that *some* improvement could be expected on the newer framed Monsters, but not as significant an improvement as on the *hoop* framers.

They reiterated your comment:
The Nichols bolts (actually studs) fit the hole better, are slightly larger in diameter, and are made of better material
The explanation given for the large *shoulders on the nuts was simply that they use a larger hex size on the nut so the shoulder just moves said nut outside the frame for easier access with a wrench or socket.

I guess I'd like to hear from someone who has actually used the Nichols engine mounts on a newer frame... hard to quantify *some improvement*
 

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Discussion Starter · #10 ·
What I think happens is that the front end impact causes the frame to flex at the one intersecting bar between the two engine bolts. With the frame bending, the result is the two engine mounting bolts pulling away from each other. When that happens, the engine casing breaks at the bolts.

The engine needs to be beefed up around the frame bolts and/or there needs to be a bar on the frame between the two engine mounts to prevent this kind of impact stress from braking the engine.
 

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This is just speculation, but I doubt if the frame flexes out in an impact. I think it's just the momentum that breaks the case.
 

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What NCR (I guess) did 1992:



888 Corsa, 1 of 26 built.
 

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exertus said:
What I think happens is that the front end impact causes the frame to flex at the one intersecting bar between the two engine bolts. With the frame bending, the result is the two engine mounting bolts pulling away from each other. When that happens, the engine casing breaks at the bolts.

The engine needs to be beefed up around the frame bolts and/or there needs to be a bar on the frame between the two engine mounts to prevent this kind of impact stress from braking the engine.
The bolts you refer to are actually through bolts so there is only one in each location. They can't apply the load you refer to. I think Norm is probably right.
 

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ducpainter said:
exertus said:
The engine needs to be beefed up around the frame bolts and/or there needs to be a bar on the frame between the two engine mounts to prevent this kind of impact stress from braking the engine.
The bolts you refer to are actually through bolts so there is only one in each location. They can't apply the load you refer to. I think Norm is probably right.
I _think_ he's suggesting a pair of horizontal frame members joining the front and rear engine mounts on each side. I can sort-of understand why someone might want that, but _geez_ they'd get in the way of a lot of other parts...

Back when I used to fly model airplanes, they had a saying which went something like "build them to fly, not to crash" - the underlying truth being that you can make things stronger and stronger to reduce the damage they suffer on those (hopefully rare) occasions you happen to crash them, but all that strength quite often adds complexity and weight, all of which you need to deal with and haul around all the rest of the time when you're _not_ crashing. Seems to me to be equally applicable to motorcycles as it is to model planes - the solution to the problem of cracking engine cases when you hit something too hard isn't "make the frame stronger", it's "don't crash!" ;)

big
 

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Horizontal in which plane? Forward/aft or front/rear?
 
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