What causes Carburetor jetting issues, rough idle or stalling on the Qj Motor Sv300?

Cold start behavior, idle quality, throttle response smoothness Estimated fix cost: $30-$80

What causes Rectifier/regulator failure, battery not charging on the Qj Motor Sv300?

Battery voltage at idle should read 13.5-14.5V Estimated fix cost: $40-$120

Oil streaks on fork tubes, soft or bouncy suspension feel Estimated fix cost: $60-$150

Test all lights, signals, horn before buying Estimated fix cost: $20-$60

Known issues to inspect before buying a used Qj Motor Sv300. What to check and how much repairs cost.

MODERATE

Cold start behavior, idle quality, throttle response smoothness

Fix cost: $30-$80

SERIOUS

Battery voltage at idle should read 13.5-14.5V

Fix cost: $40-$120

MODERATE

Oil streaks on fork tubes, soft or bouncy suspension feel

Fix cost: $60-$150

MINOR

Test all lights, signals, horn before buying

Fix cost: $20-$60

☐Check for oil leaks around engine cases

☐Test charging system with multimeter

☐Inspect frame and welds for cracks

☐Verify VIN and title are clean

Decent budget bike, maintain religiously or problems multiply