Ask for help. Harvard H6 idles from 1300 to 1400 rpm every morning, and it drops to 700 rpm in about 5 minutes. What is the problem and how to solve it?

What should I say? If your idle speed was not that high before, you can clean the air intake, especially the air filter, and then clean the throttle without changing it, which is usually one of two problems! If it is not changed, it is an oil problem, but the possibility of refueling is low! Because the oil chosen in summer and winter is a little different! Use low viscosity oil in summer, because it has good fluidity at high temperature, but it is the opposite in winter! I hope it helps you!