I been thinking about an aluminum smaller tank for CB750.
Found a couple today & got the CHEAP..
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Have to mod them but less work that starting from scratch.
One is Suzuki dirt bike, the other is TL 125 or 250.. Oddly enough the TL tunnel almost fits a 750 frame except for the front.
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, back & petcock, would have to be changed a bit unless you maybe tried to run dohc sidecovers.. dont hold much gas though..
Man are they light, like about 4.5 lbs with gascap...
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Sure would look killer , polished , & in the sun..