Suzuki 2 Strokes

Hi, working on my 500 front forks which are off a Kawasaki and held in place by older FZ600 triple clamps with gs750 rotors bolted to a gt750 hub and need to make a bracket to mount a pair of SV650 calipers, but I only have room for a 1/4" spacer and I don't feel safe making it out of Aluminum that thin. Is that to light and if not what grade aluminum 6061????. I have some 1/4" steel plate but it feels so heavy, such an important part so needs to be done rt. Thanks for any and all input.

I would suggest dumping those rotors and get a set from say a CBR600F3 on an FZR1000. Less weight and less offset so it's easier to fit the calipers.

Thanks tz, I will check out ebay again, I am surprised about your comment on the weight of the gs750 rotors, there much lighter than the old gt750 disc, building this to run in vintage racing so stuck with non floating rotors and twin piston calipers. I don't know if the ones you suggest will comply with those rules but I'll take a look. Thanks again.