Modern Vespa

Sure, we've all been there. But I don't think I've ever experienced a bolt as stubborn as this (on a Vespa, anyway).

2011 GTV300ie, the bottom-most of the three bolts that hold the muffler on. It was once a Torx, was at some point replaced with a hex bolt, that got stripped, and boy is it in there good.

I've already cut it into a flathead, and that didn't seem to work, so now I've drilled into it and have the relevant size extractor bit in there nice and tight. I'm using a tap wrench with it and there just seems to be NO way to get enough torque, or at least it feels like something's gonna snap in a bad way before that bolt starts turning.

So... where to go from here? Fire?! (If so, I could use a lesson on how to do it right.)

I'm also open to everyone's horror stories of various parts that just would not budge.

Thanks in advance for any help/advice!

Probably too late for this, but I invested in a battery powered impact wrench during a dirt bike revival project I was working on.

I've spun off so many stubborn bolts with it, it almost feels magical. It's not even a big boy, only 12v.

First - get that extractor bit out of there - they have their uses, but IF and WHEN it breaks you're in a whole new world of hurt.

If you can by drilling or grinding, just get that head off.

Then you can get the exhaust off. Then you can work on the bolt - a couple of nuts locked together (you can buy really thin ones) will make a good purchase point. Use loads of release fluid - PB blaster or weapon of choice (acetone and ATF 50:50 work well), let that soak for hours - rinse and repeat.

Then try heating the exhaust bracket and also use some freezer spray on the bolt itself. It should now unwind from its shell.

If all that fails, drill out the bolt as much as possible until you can dig the remains out, and consider using a helicoil in the probably damaged thread.

If you cut or grind the head off, you can get the muffler off.
I would recommend taking the swingarm off, and taking it to a machine shop. They take broken studs out of engines all day.

Yeah, at the rate you're going you will end up snapping it off flush, removal then becomes a much bigger job.

I had issues with exhaust bolts on my S, I now use anti seize on these.

Last time I had a stripped bolt I got so fed up with it I traded the bike in for a Vespa. LOL