If you have a $120 budget for a frame what is your budget for building it?
I am sure with a little hunting you can find a decent quality bike that you can then customize as you want it.
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk