Increase your fuel tank by 1.5-2ltr for free.. Drill an 8mm hole in the filler neck on the natural lip of the thread..
8mm hole..

Warnings.. This allows the tank to be filled to the brim so don't leave it without expansion room in the sun. And no suing me if you get swarf in the tank.

I have performed this on a Softail fat bob but I’m guessing that this should work on others that use the same filler neck..

 

No thanks... You'd have to fully remove the tank and then make sure no metal is left over in the tank. Not to mention...it's always going to leak thru your overflow when topped off.

 

You mention the swarf and expansion risks. You forgot: drill->spark->gasoline->ka-boom!

 

I doubt a bit of swarf in the tank will make any difference. There's two filters (IIRC) between the tank and the injectors.

There are many bikes riding around today with shitloads of crap in the tank.....

As for the spark issue. Well....yes. You'd either needs the tank off, empty and dry - or perhaps use a ceramic drill bit?

But that's a good idea. I wondered why the filler neck in these tanks went so far down. Having said that, I seem to manage to fill mine up to nearly the top of the filler neck anyway. Just takes a bit of patience......

 

Less than a 1/2 gallon increase...that'll get me a whole 15 miles.

 

I think I'd rather pipe some gas cans from my saddlebags.

 

It'll get you 24 miles on a 114" Fat Bob. And take your max range to 200 miles per tank.

 

Your bike.... do as you see fit....

Back in the day, we used to call those kinds of fixes/mods a Mickey Mouse repair or Mickey Mouse mod... and no it wasn't supposed to be a compliment...

"That guy really Mickey Moused his (bike/car/truck)."



There was a guy in high school with a Plymouth Duster. Instead of buying headers and/or new mufflers, he just drilled holes in his mufflers to make them louder...

Like this mod, it worked.... but.....

 

 

Insane!
Not for me thanks