1974 DT360 Bog/Idle Issues

Hey,

I have a 1974 DT360 that has been my most reliable bike for a long time, but it recently has been bogging down when put under load (ect. small hills) and when the throttle is applied. I have been able to get over the bog by shifting down and getting in the higher revs of a lower gear, but it is kind of difficult to do when you're going up a hill. I've tried soaking the carb in carb cleaner for a day or so, but that has only made it idle funny. When I stop it, the idle gradually increases until it hits the rev limiter or the red line. I've run out of ideas, so please help.

Thanks