My 1996 Suzuki VS-1400 Intruder chopper (my old avatar) was specified as air/oil cooled and did indeed have and oil cooler from the mfgr. The VS-800 Intruder was water cooled. The GZ is third world transpo designed to have low maintenance, cheap to run, and excellent longevity. If the GeeZee needed an oil cooler, Mr Suzuki probably would have put one on.
Parade duty Harley's have massive oil coolers. All the 09 Big Twins have an auto rear cylinder shutdown for overheating. (also has manual control by twisting the throttle grip
Backwards....hmmmm)
If I get stuck for over 10 mins in traffic I'll find an alternate route. I'm smart enough not to sit there and let the bike (or me for that matter) overheat. Duh.
If the bike is overheating it's too damn hot to ride anyway. It's Guinness time!!