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Discussion Starter · #1 ·
Finding confusing info on the net.

Can anyone tell me the correct torque setting for the flywheel/alternator rotor-nut?

My workshop manual says 176,5-186,3Nm. No mentioning of Loctite whatsoever. Not sure if my manual is the correct one for the modelyear ('97) I own.
Then searching the net: some say 140ft/lbs (=190Nm), another one says 157Nm, yet another one says 330(!!)Nm... :|

So if anyone can give me the correct setting (and any info on Loctite use), it would be most helpfull.


My setup: all stock flywheel and retaining nut. This is a single nut with a flange. Bike is a '97 900SS (last year of the carb. models)
The nut is a tight fit, I can't screw it on the crankshaft completely by hand. So I think it's the better version of the nut (not the one where the threads are too loose).
Flywheel has no holes in the side for any C-shaped tool. Just one hole (for a holder tool) right besides the alternator rotor).



And one more question: (although this is not a huge problem, I can always assemble it and test it before putting everything back together) the sprag clutch has an arrow on one side. Should this arrow be one the back of the flywheel assembly (facing the engine) or on the front (facing away from the engine, and not visible when looking at the clutch from the circlip-side)?
Yes, I know, I should have looked when I dissasembled it but I placed the sprag clutch on a table the way it came off and my youngest daughter knocked this table over...
:frown2:
 

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your bike has a single phase alternator, spec is 185nm. the other specs you list are for, in order, 3 phase alts (original spec, since upgraded to 270nm), single phase 600/750 and late st3. you need to go with the spec for your model. i would use a strong thread locker - green loctite or wurth.

for the single phase alts there's a tool that goes over the ribs on the front of the rotor that you use to hold it while tightening the nut. some people use things to jam the timing gears i believe.

if you have the flywheel assembly on the bench in front of you, with the gear up, the gear should rotate freely to the left (counter clockwise), but grab when you turn the gear to the right (clockwise).
 

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Discussion Starter · #4 ·
Thanks belter and duvet for this very clear information! Much appreciated and really helpfull (again).
 

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When I got an SS, I was warned to look out for two things, frame cracking in the top rails in front of the tank and the alternator nut coming loose.

Both happened.
 

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flywheel nut ...

This is the torque settings page from the Ducati Workshop Manual:

Text Electric blue Font Brand Logo

Fred
 
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Discussion Starter · #7 ·
When I got an SS, I was warned to look out for two things, frame cracking in the top rails in front of the tank and the alternator nut coming loose.

Both happened.
I knew about the frame cracking when I bought it so I double checked the frame and there were no cracks.
I might be wrong but I think I once read that the later models (mine is a '97) didn't suffer from frame cracking anymore.

Didn't know about the nut problem when I bought it but that also seems no problem on my bike. I had to take the nut off with a rattle gun. Tight as hell.
And again; I know there are a few differences between the early and later models when it comes to that nut. I believe (and hope) that the later model nuts were designed beter than the early ones.
 

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I knew about the frame cracking when I bought it so I double checked the frame and there were no cracks.
I might be wrong but I think I once read that the later models (mine is a '97) didn't suffer from frame cracking anymore.

Didn't know about the nut problem when I bought it but that also seems no problem on my bike. I had to take the nut off with a rattle gun. Tight as hell.
And again; I know there are a few differences between the early and later models when it comes to that nut. I believe (and hope) that the later model nuts were designed beter than the early ones.
Let's hope you continue to be luckier than I was. IMHO, the frame cracking is largely due to the incredibly harsh front suspension, which causes the frame to deflect because the forks don't. Once Ducati UK supplied me with a new frame, I therefore drained the oem 7.5wt fork oil out and replaced it with 5.0wt.
There is a guy on the DucatiUK forum who sells bolt-on frame braces.
 

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When I started at the dealership in 97 they had been offering a alternator reliability service for years prior. The flywheels falling off were well known and was a very easy fix (loctite). I was told the factory engineers felt loctite was not a "correct" fix so they kept trying to redesign crankshaft nuts instead of adding a drop of thread locking compound.

While I was there there were 2 updates to the nut neither of which solved the issue, our loctited bikes were problem free. Starting in 2001 the problem was mostly solved, that was about the time Ducati started using thread sealant. Of course at the same time Ducati also started buying every bolt pre-loctited and suddenly we could not get front fenders off without destroying the fender clamps...lol.

Many bikes were done this way by many shops/owners as it was a known issue. If I see a paper gasket it is a safe bet the mod has not been done. however a liquid gasket was not used on early engines so if you see sealant it may already be done.

While you are there also
loctite
starter bolts
layshaft nut
shift arm bolts
make sure to inspect the shift arm for wear and adjustment .
lighten flywheel
condition of starter clutch.
 

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Of course at the same time Ducati also started buying every bolt pre-loctited and suddenly we could not get front fenders off without destroying the fender clamps...lol.
what a clustercuss that was. 1098 fuel pump plate screws too, with those stupid 3mm hex heads.

and the disc bolts with the t40 heads. the t45 are fine, but i've broken so many t40 bits. even with heat.

stupidos.
 

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Maybe someone could help me with regard to flywheel nut torque setting. I have a 1999 Cagiva Gran Canyon which has,I believe,basically a Monster 900 engine.The Haynes manual states 157 Nm for all Monsters but I think that is for the earlier carb engines. My engine is injected so suspect it should be the higher setting of 180 - 190 Nm or so.Also, what is the torque for the alternator rotor bolts that attach to the flywheel,and locking agent recommendation.Any information gratefully received.
 

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from memory, the gc is a 3 phase engine, so 270nm is what i would use. and a new nut with red or green loctite. i use wurth green, it's really good shit.

those m6 screws i would use blue loctite and 14nm.
 

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from memory, the gc is a 3 phase engine, so 270nm is what i would use. and a new nut with red or green loctite. i use wurth green, it's really good shit.

those m6 screws i would use blue loctite and 14nm.
Thanks for that. 270 Nm seems really high and I don't want to strip anything.The various pieces of information don't mention a torque that high.
 

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Ducat later revised their original spec, that is why you find conflicting info. The 3Phase alternator models are 270nm on that nut, or 190 foot pounds. It is better to use a new gland nut and locktite (works as lube too) so you don't strip anything.
 

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Ducat later revised their original spec, that is why you find conflicting info. The 3Phase alternator models are 270nm on that nut, or 190 foot pounds. It is better to use a new gland nut and locktite (works as lube too) so you don't strip anything.
Thanks RockAz and Belter. 270 Nm it is.I find a lot of conflicting info on the net but good to have guys like you who know.
Cheers
 

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Now it is up to you to verify that you have a 3-phase system before bringing out the big breaker bar -
 

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red or green thread locker -( I use Wurth-just because it's easy) --and use the German torque spec--- Gootentite
 

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loctite 242 is blue, 262 is red and 270 (which may have been replaced) was green. wurth blue is like 242, wurth green is like 270 - use heat or you might break something.
 
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