I'm going to resurrect and oldie here...found this thread while searching for tips on a problem
So I actually did manage to strip one of these cam bridge bolts. They were torqued correctly last time but I'm wondering about my torque wrench calibration at this point. I think it was more a problem of my hex bit not fitting entirely square due to tight access and maybe my XXXL mitts and too much force have something to do with it.
Anyway, I spun my craftsman hex socket attachment in the screw, then tried a T30 torx bit with a ratchet handle and eventually spun that too.
After regrouping overnight, I realized I could get a straight shot at the bolt if I removed the rear fender, so did that, and then my Dad came to the rescue with tools - we managed to get a little bit of grip in the bit with the better angle, and we first tried a makita battery powered impact wrench, which didn't have enough force to turn the bolt, and then we tried my new favorite tool:
Something like THIS:
Basically you whack this thing with a hammer and the force of the blow pushes the bit while rotating it, to knock the bolt loose.
Honestly I was having visions of having to drill out the bolt, etc and this tool saved me - three whacks with a dead blow hammer and I managed to break the bolt loose.
Plus in the spirit of Top Gear Jeremy Clarkson this adds one more use for the all-mighty hammer - loosening bolts!
The threads on the bold looked good, so honestly no idea why it bound so hard but all is good now, and it was kinda fun that my dad saved the day with the old school man-tools...
Word to the wise - if you do a lot of valve checks like me and/or see any rounding just buy new bolts (they're not expensive)