Are you allowing the engine to warm up before touching the throttle?
Any oil that is JASO certified is good to use with a wet clutch. That is part of the certification standard. Almost all motorcycle-specific...
You can't. The rubber is heat-molded to the steel. You can wire brush the paint off and electroplate the visible metal in nickel at home though.
The jet needles are also different for the 750 than for the 650. Those will need to be swapped into the 650 carbs Are the air jets in the correct...
That the rear tire is warmer than the front would be expected. The final drive is partially cooled by the rear wheel.
The pistons need to go into place before putting the cylinders on. This isn't a car engine.
