I just had this same thing happen w/ my new 2012 650 I believe. The nut had been stiff from the first change but I had never backed it off more than a couple of turns. It was stiff enough coming off this past weekend that I had to use a breaker bar to "help" it rather than the Craftsman closed end wrenches I'd been using. I pulled it out and about 2 threads on the axel about a 1/2 inch in (flush w/ the outside of the swing arm) were pretty much ruined and the inside two threads on the nut were ruined also. Strangely enough the nut spins off and on by hand just fine and the outer threads on the axel are just fine. It's like there was a bur on the axel or something and it ruined the threads on the nut. After multiple chain adjustments they were pretty much melded into each other. I took it into the shop and they took pictures and within just an hour or so Suzuki had decided to warranty the axel. They did tell me I had to use a torque wrench which I have already but nothing else was said about it. I wonder if the damage was there from when it was originally installed because I had tried to torque it the first time I adjusted the chain and couldn't get it tight. I thought maybe it was because my wrench only went up to 75 ft. lbs. but that probably doesn't make sense now that I think about it. I just ended up snugging it w/ the closed end wrenches but this past time it just bonded itself together and wasn't coming off. The shop put it back on and I am riding it until the replacement arrives.

My theory has been to install with what you might have to use to remove. I use the oem axle tool for both install and removal.. I haven't tried it, but I am afraid I wouldn't be able to get the nut off in a roadside pinch if it had been torqued upon installation. 45 plus years and have never had an axle come loose. Not changing procedure now.

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79 GS1000S
97 TL1000S
2002 Concours
2005 DRZ400
2005 KDX220R
2007 DLK
2009 KLR650

Good theory! For that very reason I carry a tool roll containing "real" tools in the side case anytime I venture more than a few miles from home. They are the same ones I break out when it's time for a chain adjustment. I'm not thrilled about the idea of having to use the factory tool kit unless there's just no other option.

+1
Mike

Wanna bet that mechanics who have that 'gentle' touch know instinctively how much torque to apply to any given fastener? They can feel how much tightening to apply using a 1/4", 3/8", or 1/2" drive ratchet to a fastener with a certain sized head is correct? They quickly look at the thread pitch, fastener size, and heat/cooling cycles to ascertain how much torque to apply along with whether there is a need for a thread locking compound or anti-seize.

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'92 Honda Z50R
'94 Kawasaki KLX250 modded to 340cc's
'00 Yamaha YZ426F
'94 Yamaha 125 scooter
'05 Vespa E4 scooter
'68 Vespa VBB scooter (restored)
'06 Wee
'03 Honda S2000 roadster