Check spark plug cap. Drain puke tube. Do you wait for self-check to complete before starting? Do all warning lights go out after it finishes self-check (except oil)? Recently my DT300i, which ALWAYS starts in two revolutions, became reluctant like yours. Battery voltage while cranking was down to 9.5 volts. Anything below 10.5 volts means replace battery. Like Stig said, your battery is probably the culprit. Yuasa the best.