Lifter noise is a typical thing for the G1. But what's happening is the valves are getting stuck when the engine is cold. They'll loosen up once the motor is hot. There are some stuff you can do like adding ATF into the crankcase since it had detergent to clean stuff up. I need to look into that first so hang on a bit while I confirm on that.
The idle issue, where does the tach needle sit? Things you can try doing is cleaning the throttle body, change air filter, and adjust idle screw.
The idle issue, where does the tach needle sit? Things you can try doing is cleaning the throttle body, change air filter, and adjust idle screw.