That almost needs a wheelie bar without even giving it gas..

So, here is the first attempt. 7068 aluminum. 5.45 oz instead of 14+oz.
And that's without the right side steel spacer.
Haven't done the deflection test.
Instead of the right side spacer, I left the axle full thickness so that it shoulders against the right side wheel bearing. That means that the right fork leg doesn't have a spacer to rest against, but then again, a lot of new bikes do it like this.
Reason of this is that I get to take advantage of the larger axle diameter for a much longer distance. In shafts, strength increases as does the square of the diameter.
With the holycrap fork brace, I'm sure the lower legs will be where they are supposed to be.
Guess I'll find out.
Of course, the real load comes from the left side under braking. The next generation will have the axle coming in from the left.
A bit more work.....

Armen wrote on 10/08/19 at 12:14:56:

Or larger ID bearings?

I think bearing mfr's are evil, why aren't bearings available in every OD and ID?

Edited:
Ohhh, c'mon, look at how the axle is loaded and supported.
My forks were snapped off and the sliders were pinching the tire. The axle IS bent, but I had to roll it on the drill press to see it.
I'm not about to go drilling one, because I don't think the performance gain from the weight loss would justify the effort. Not because I'm afraid of the axle crapping out. Well, depends on the hole diameter you're thinking about..

Armen,
Yes you can get great aluminum.
no matter what you do, aluminum will flex 3 times more than steel.
It's in the young's modulus.
Higher strength just means it can flex more before it breaks.
And the harder the material is, the more likely it is to break than give you a tell tale bend.
That tale is a warning... replace me.

Versy,
That's why I did the deflection test.
The stock axle moved about .004" and the 7068 about .005". Not three times the flex. the thicker right hand section of the aluminum, and it's holycrap qualities account for that.