That is a Suzuki DR350. A lightweight dual-sport motorcycle from the '90s with an air-cooled, 4-stroke, 350cc engine, and a 6-speed manual transmission.
Lightweight and bulletproof.
DR350s are still sought-after by some specifically for the low weight, simplicity, and 6-speed transmission. Many dual-sport enthusiasts are adamant that having the extra gear vs a 5-speed is a huge benefit, and i can tell you from my own experience: they're right.
