Yep, what everyone is saying. Those hand throttles are maintenance pigs. I have to take mine apart, clean, and adjust it at least once every 30 or 40 years. ...
It's likely to take almost an hour to do it right if I just sort of pick at it while cleaning the shop and lubing the front axle.
But just like all one hour jobs it takes longer - especially if I am doing it again because I forgot a part the first time. But it's one of those things that works so well when you get done that it's a pleasure.
rScotty