Join Date: Jan 2002
Location: Auburn, WA 98401
I have owned a '93 Zephyr 1100 since new. Make sure the motor has not been over filled with oil, even a little. That will appear as a mysterious oil leak. Try changing the oil and make sure you measure accurately the oil volume you add. Make sure you have the owner's manual or the factory service manual to find out the oil capacity with and without an oil filter change. I am not sure about the 750 but the 1100 has two oil plugs, if you remove only one then the volume of oil you add is slightly less.
The "burning" issue is vague. Could be the rings, that is my best guess with what little information you have provided. Those motors are pretty durable, however, but if someone mistreated it, it won't matter how hardy the motor is, it can still fail.
"...If you can meet with triumph and disaster, and treat those two imposters the same....you'll be a Man, my Son!"
- Rudyard Kipling