I weighed my dp GL plus last week and it was about 11kg. That's with a set of skyways.
I've not weighed it yet but the wife's Aero Reflex is a LOT lighter!
i used to have a dp firebird freestyler in 80s, the frame cost me £75 new i think, cant remember if it was light or not,
i remember a friends silver streak 2 was 21lbs
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but it was horrable to ride because the crank felt too far forward.
i would like an old dirty light oldskool bmx with skyways oneday, but at the moment im just window shopping