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Discussion Starter #1
As everybody (ahem) with Carrozzeria wheels mounted should know, you're only supposed to torque the wheel nuts to 1/2 the manufacturers' torque specs. Apparently Carrozzerias use larger wheel bearings which don't require as much torque as standard bearings, and, according to the folks at Carrozzeria, if you do torque the wheel nuts up to factory spec with Carrozzerias, you run the risk of pinching the bearings.

In the case of the Sport Classic, the Ducati factory spec wheel nut torque (as per the Workshop Manual, not the Owner's Manual) is 150 Nm rear and 63 Nm front, which halved would be 75 Nm rear and 31.5 Nm for Carrozzerias.

To make a long story short, I just realized that my Carrozzeria mounted wheel nuts were torqued up to factory spec, so I loosened them to Carrozzeria spec. I'm not terribly worried about the rear wheel, being torqued to 75 Nm but the front wheel at @ 31 Nm feels like its got almost nothing holding it on. With the Carrozzeria spec torque, there are only a couple of threads visible at the end of each axle, so there's not enough room to put a lock nut or drill for a cotter pin. Anyway, being a paranoid, I'm concerned that the wheels nuts will eventually work themselves loose allowing the wheels to come loose/ off at speed.

Anyway, short of the time, money and aggravation necessary to dig up some slightly longer axles or constantly checking the wheel nut torque, I am wondering if a Loctite product could be used on the axle threads to secure the wheel nuts, and if so, which Loctite product should be used.

Any other suggestions?

Thanks!
 

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I would rather run the risk of pinching the bearings than having the wheel fall off! Seriously though. If you're thinking the nut needs locktite, then you really should tighten it up a bit more.
What did I do when I put the new rims on? Tightened it up until it felt right. Seems to work. If I run the risk of damaging the bearings, ah well. They're cheap. I sure as hell wouldn't run around with a loose wheel nut. Are you crazy?
 

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just safety wire the axles.
 

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I'm trying to understand where this lighter torque spec comes from. Do the Carrozzerias use a different spacer between the bearings? Softer material than stock? Torquing the axle nuts shouldn't put extra pressure on the bearings as it only squeezes against the inner race, it doesn't add tension to the bearing or change the bearing "play", unless the inner spacer is not the corret length or it flexes/squeezes under pressure.

The rear nut need to be tight enough to keep the wheel from moving under load (hard acceleration caused a friends bike to almost throw a chain the other day when the wheel shifted). There is some debate about the correct factory spec for the rear nut. I use about 75 ft.lbs. If the front nut comes off you still have 4 pinch bolts holding the axle in place....but still, I wouldn't go less than factory spec on that nut. It's not the heavy to begin with.
 

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I'm trying to understand where this lighter torque spec comes from. Do the Carrozzerias use a different spacer between the bearings? Softer material than stock? Torquing the axle nuts shouldn't put extra pressure on the bearings as it only squeezes against the inner race, it doesn't add tension to the bearing or change the bearing "play", unless the inner spacer is not the corret length or it flexes/squeezes under pressure.
Thank you, Dietrich. I was wondering the same thing. It's not like these are preloaded tapers (like on my old BMW), they're ball bearings.
 

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Discussion Starter #6 (Edited)
I'm trying to understand where this lighter torque spec comes from. Do the Carrozzerias use a different spacer between the bearings? Softer material than stock? Torquing the axle nuts shouldn't put extra pressure on the bearings as it only squeezes against the inner race, it doesn't add tension to the bearing or change the bearing "play", unless the inner spacer is not the corret length or it flexes/squeezes under pressure.

The rear nut need to be tight enough to keep the wheel from moving under load (hard acceleration caused a friends bike to almost throw a chain the other day when the wheel shifted). There is some debate about the correct factory spec for the rear nut. I use about 75 ft.lbs. If the front nut comes off you still have 4 pinch bolts holding the axle in place....but still, I wouldn't go less than factory spec on that nut. It's not the heavy to begin with.
You got me -- that's just what Carrozzeria says in their installation instructions -- only torque the wheel nuts to 1/2 factory spec., whatever factory spec may be. According to the folks at Carrozzeria, they only tighten to 1/2 the factory torque because the Carrozzeria bearings are "larger" than standard bearings. I haven't a clue as to why this would cause the bearings to get "pinched" if you torque the wheel nuts to more than 1/2 factory spec.

Carrozzeria does use their own spacers, which often don't fit correctly on the Sport Classic, so you have to fabricate your own in order to get it all to fit right. I also had to use 996 rotors to get it all to fit with the 4 pot Brembos that Carrozzeria supplied in their "works kit" a while back. So much for Carrozzeria's claim that this is a "bolt on" wheel for the Sport Classic, but Carrozzeria was the first (and maybe only) manufacturer to offer a "bolt on" alloy wheel for the SC line. Just another aggravation due to the fact that Ducati has never offered a factory alloy wheel option for these bikes. Other than that, they seem extremely well-made, they're good looking and they're some of the lightest wheels short of BSTs.

The 1/2 torque thing sounds odd to me, too, and I certainly wouldn't want to under torque the wheels so that they come loose or jerk the rear wheel forward so the chain comes off while riding.

I have to say, I've been running these wheels for 2500 to 3000 miles apparently at the Ducati spec torque (as per the Workshop Manual) of 150 Nm rear, 63 Nm front, with no apparent ill effects. So, I guess if the Carrozzeria bearings wear out prematurely due to using factory torque, I can get them replaced or maybe put some "standard" bearings on that can be torqued up proper.

BTW, what would the early signs of bearing wear/failure be so I can replace them in plenty of time?

Thanks!
 

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Carrozzeria does use their own spacers, which often don't fit correctly on the Sport Classic, so you have to fabricate your own in order to get it all to fit right.
Those aren't the spacers Dietrich was talking about. He's talking about the spacer in-between the bearings - inside the hub.


The 1/2 torque thing sounds odd to me, too, and I certainly wouldn't want to under torque the wheels so that they come loose or jerk the rear wheel forward so the chain comes off while riding.
The chain adjusters prevent that.

I have to say, I've been running these wheels for 2500 to 3000 miles apparently at the Ducati spec torque (as per the Workshop Manual) of 150 Nm rear, 63 Nm front, with no apparent ill effects. So, I guess if the Carrozzeria bearings wear out prematurely due to using factory torque, I can get them replaced or maybe put some "standard" bearings on that can be torqued up proper.
I can't imagine that the "larger bearings" swap out with stock Ducati bearings. They have to have the same I.D., but, if they're larger, they undoubtedly have a larger O.D..

BTW, what would the early signs of bearing wear/failure be so I can replace them in plenty of time?
Noise, play, roughness when turned when up on a stand, and, if left too long, they'll spin in the hub and ruin the wheel.
 

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I just can't believe that the 150 NM figure for the rear wheel is correct when the figure for the Multistrada 620 rear wheel is 83 NM. That's what I've been using on my GT1000.
 

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What's the method to safety wire the axles?

Thanks!
Before you start, buy a bunch of 1/16 inch drill bits and just break about 2/3's of them before you start and you will be on the road! (I know that doesn't make sense now but soon enough, you will understand.)

Does your axle stick out past the the tightening nuts at all?
 
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