They're universal if you use them as throw-overs and don't bother with the racks. Straps for that are supplied.
As mentioned I've used Oxford Lifetimes for years with no racks on my hoop type Monster.
The side racks are easy to mount on homemade brackets anyway. I reckon a couple of P-clips on the grabrails would do the trick. Even if it needed a light brace down to the pillion rests, but was never needed with the Oxford throw-overs.
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