Okay.. What did I do wrong ?

[showkey]

Another set of data points on the sprocket.

My 2012 virgin sprocket bolts when checked with a beam style torque wrench:
Checked half the fasteners loosening and half tightening

When tightening or add torque the nuts begin to move at 90 ftlbs. Concluding they are likely tightened to 80 ftlbs at the factory. ???? ( 3 were thightened)

When checked in a break away mode ( loosening) they measure about 65 ftlbs (remaining 2 were loosened)

The dot on the end of the stud. I believe indicates high strength material. Looking for confirmation.

 

[b_rubenstein]

In a company like Honda no one is individually tightening those nuts by hand with a torque wrench or calibrated air gun. They designed a machine that runs all the nuts down to the proper torque setting. There's also probably a test fixture to make sure the torque values are within spec. and how often it has to be checked.

So not chase those threads with a die. if there is any corrosion, use a hand held wire brush. Those nuts have a locking mechanism to keep them from unscrewing; don't use locktite.

 

[rjarrell]

This is when you wish thad been done by the dealer

 

[showkey]

This is when you wish thad been done by the dealer

At this point we still do not know where the error was made ..........

While the 80 ftlbs seems a little high torque value, its in the range for high strength 12 mm fasteners.
It is very clear the stock nuts and studs will easily with stand 80 ftlbs confirmed by several members.

The wheel is a sub assembly so it does not have toque verification makings like the assembly line installed part have. There is another verification process for sub assembly parts. The white marks on critical fasteners installed and torqued on the line are marked.
When they are torqued they are marked and verified by another person.

Examples of the torque verifications marks:

 

[kumatae]

The used rear sprocket hub on eBay that I mentioned few posts back is now relisted at $20 shipped. Someone could use it to test it.

12 Honda NC700X Rear Drive Hub & Sprocket 3C | eBay




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[rymech]

The used rear sprocket hub on eBay that I mentioned few posts back is now relisted at $20 shipped. Someone could use it to test it.

12 Honda NC700X Rear Drive Hub & Sprocket 3C | eBay




Sent from my iPhone using Tapatalk

Tempting...

 

[rjarrell]

Sorry you are having these problems. Did you come up with the a Fix! I'm sure this will probably happen to others.

Okay... Seems clear to me that they may have been over-tightened, now why only 2/5 were over tightened and the other 3 held I don't understand, but whatever.

Could the TQ wrench be out of cal? Sure, it's not an expensive wrench, it's possible.

But beyond all of this advice about how a problem occurred, what I could really use is some advice from so many of you guys who know more about bike maintenance than I on how to fix it.

Thanks friends.

 

[supertux1]

I am in the process of changing my chain and sprockets. Most of my rear sprocket bolts crack free at about 30ftlb, but when checking their initial tightness the are at least 70ftlb, leading me to believe 80ftlb is correct.

I am cracking the bolts loose while the tire is still on the bike and doing it in a star pattern:

Interestingly enough, the studs broke free when loosening. I'm pretty sure that's not supposed to happen:

The hub thingy is not steel, magnet won't stick but the studs are magnetic.

There's some white powdery substance on one of these:

Probably some threadlock compound that didn't take?

Clean and inspect the spacer and bearings. Feels good. Loctite on deck for the loose studs only. Too chicken to use red.

New sprocket installed. Torqued each bolt four times in a star pattern adding 20ftlb each time, to 80ft-lbs. Problem children marked for later inspection:

 

[AsureDawn]

If there is thread lock, that may be why the stud came out with the nut. Shouldn't need any, on the stud or the nut, especially with the torque that's used.

 

[supertux1]

If there is thread lock, that may be why the stud came out with the nut. Shouldn't need any, on the stud or the nut, especially with the torque that's used.

This is the first time I've had it off. There appears to be some kind of factory installed compound in there.

Got everything back on:

I

(Yes the bolt is on there... you would believe how much gunk is under there!)

It's late, I'll do the new chain tomorrow.

 

[b_rubenstein]

The hub is an aluminum alloy, the studs are steel and plated to prevent corrosion (possibly clear zinc dichromate). Add in water and moisture and there's a little reaction resulting in the white powder. There certainly seems to be some thread locking compound on the end of the stud that goes into the hub. It's important that the nut rotate on the stud, and not the stud rotate in the hub, because that can cause the threads in the hub to get stripped. If the aluminum threads do get stripped, an insert can be used to repair it.

 

[supertux1]

The hub is an aluminum alloy, the studs are steel and plated to prevent corrosion (possibly clear zinc dichromate). Add in water and moisture and there's a little reaction resulting in the white powder. There certainly seems to be some thread locking compound on the end of the stud that goes into the hub. It's important that the nut rotate on the stud, and not the stud rotate in the hub, because that can cause the threads in the hub to get stripped. If the aluminum threads do get stripped, an insert can be used to repair it.

Good to know. I just put the thing in the way it came out, with a little blue loctite. The stud bottoms out and then locks up good, it can't move forward so that stops any additional torsion on the aluminum threads. Then the nut turns.

 

[Ponyperformance8]

Thanks to everyone for your help. The ole NC is back in action. Got the new studs they went in fine with a bit of thread sealant and torque to 60 ft lbs.. increased incrementally from 40.