I think a couple of welded on lugs (onto the yoke tube) would be the best option, which the bracket/frame can bolt to. Preferably don't weld over the frame number!
The yoke could feasibly be drilled and tapped to bolt a bracket to it, but the tube is not really that thick. (And use short bolts that don't hit the inner stem and seize the steering!)
I prefer to have the capability to point the headlight beam in directions other than that the bike is pointing in, but that's just me
Looking at some of the bracket options on the web, it might be feasible to drill through the frame gusset behind the steering yoke tube to allow for mounting bolts. Probably the least "intrusive" option.
Some more photos would be really appreciated, even 2 years later.
Plus a list of parts used and parts fabricated.
S'pose since this is 2 years old, the op is off riding the world, and this is his 1 day!
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In the Riverina.
'73 RD250, '80 XS1100, '81 RD373LC, '96 Tiger 900/sidecar, '02 TTR250, and another XS11 - this time a chain drive Period 5 race bike that may be ready to race eventually.
Well mine is more of a mini fairing/wind shield/gps mount than a tower...but it works for me.I got it in the sale at Ali express for around £100 GBP Inc delivery and taxes. For the money I really can't fault it!
£115.99 | Universal GPS Mount Bracket Mini Fairing Kit For KTM EXC 300 Husaberg Husqvarna Honda Beta GasGas Yamaha Suzuki Kawasaki Sherco