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Discussion Starter #1
Grrrrrr..

Changed the oil on the bike and found a defective filter cover bolt.
Specified torque is 9lbs (12 newton meters), which isn't a whole lot so I used the torque wrench and torqued them in increments. The first three bolts went without a hitch but the last one twisted with just 10 newton meters of torque.

The bolts are made out of what appears to be pot metal.
On a plus side, threads on the engine are 100% fine.
So it's off to the hardware store tomorrow to find a replacement until the dealership opens on Tuesday and I can get an OEM replacement (and a couple spares now that I know they're not exactly what I'd call high quality).

I'll be damned if I let this keep me from riding. This bike has quickly become my favorite. T'is Odd considering all the beasts I've ridden, that the weakest (by a long, loooong shot) is the one that wiggled it's way deepest into my heart.

On Edit: This isn't meant to be a rant but rather a heads up for the do-it-yourself types :)
 

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Grrrrrr..

The bolts are made out of what appears to be pot metal.
On a plus side, threads on the engine are 100% fine.
So it's off to the hardware store tomorrow to find a replacement
Are you sure it's the bolt that went bad and not the threads of the block? I've never seen that. It is always the other way around. I think you will find that what you are looking at on the bolt that looks like pot metal is actually the threads which were ripped out of the engine and stuck to the bolt. You can usually even hold on to the metal and unscrew the bolt from inside it, leaving a perfect thread shaped coil of metal behind. I think you will find that the bolt is fine but you will need to repair the hole with a heli-coil thread insert. Unfortunately, torque wrenches can be a bad thing. You tend to rely on their function with blind faith and turn off all your sense of how tight you are turning something. These super low tightening torques can easily be missed by a torque wrench working at the bottom of it's scale.
 

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Discussion Starter #3 (Edited)
I checked for that.
I removed one of the other bolts and put it in the offending hole and it tightened up fine to specs.

It is the bolt and of that I'm grateful. If it had been the other way around I would be screwed (pun intended) for a few days.

When I said the bolt twisted I literally meant "twisted. It is sitting in my pocket in two pieces. I would have used the word "snapped" but it didn't snap clean off.
Only after I removed it and picked at it did it become a 'two piece" bolt.
 

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It could be bad heat treat, or plating which can effect heat treat. did it snap near where the threads meet the shoulder? Do you remember if it seemed overtightened when you broke it loose? I was checking my fairing, and they seemed not uniformly tigh. A couple made a loud snapping sound when I broke them loose, too tight I think.

I bought some 3/8 split lock washers from a surplus near where I live. These washers, every one of them would split and fly out just before the split was completely flattened as you tightened the nut. I am sure the aircraft surplus was actually a bad lot from heat treat.

Good luck finding the bolt, I have a hard time to find motorcycle bolts at the hardware store, because they usually stock only the coarse pitch metric. I hope your luck is beter than mine in this area. thanks for the heads up.
 

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Discussion Starter #5 (Edited)
I'd say a bad heat treat as well. The bolt was pretty soft.

As luck has it, my little hardware store has a good selection of metric bolts.

M6-1.00 x 25 did the trick and the bike's back on the road :)

To answer your questions:
Yes they seemed tight when I broke them loose.
It snapped at the threads about a 1/4 past the smooth shank.
 
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