XJ550 Maxim - Oil Burn issue ... too full?

1981 XJ550 Maxim with 3337 miles.
Has always ran perfect up til today.

New owner took delivery of the bike at noon. He drove it 55 miles on the Freeway. Then called me from side of the road with "there's white smoke coming out the exhausts" (at 75 mph). Said "it lost power like it wasn't getting any fuel, engine was cutting out."
He checked and there's plenty of gas in the tank and showing in the see-thru fuel filter. Petcock is rebuilt and has been trouble-free.

Now I've run the bike pretty hard up & down through the gears and never had a problem with oil / smoke / or power loss. My last trips have been around 25-30 miles.

OIL was slightly over the required level close to the 3/4 (top) mark in the window.

Maybe a bit too full and the excess oil is burning off?

Bike sat for 16 years virtually untouched.
I've put approx. 370 miles on it since Oct. 2008.
Is it possible the oil control rings have to re-seat?
Hasn't shown any sign of trouble engine-wise up to now.

Very strange stuff indeed.

Any ideas about the slightly high oil level?
Would this damage the engine?
OR will the oil just foul the plugs?

 

Sounds like one or more cylinders wasn't firing properly or at all. White smoke is unburned fuel and the oil level you describe is nowhere near being too high. I keep mine with a barely visible bubble in the sight gage or the oil light won't stop flickering.

I would say you either have a carburetor or an ignition problem.

 

White smoke is burning oil

 

Pure white smoke is unburned fuel being vaporized. Bluish white to black smoke is burning oil.

 

Since he lives 70+ miles south in the desert I've asked him to pull and replace the spark plugs with new; AFTER lowering the oil level. Sounds like burning oil was 'drowning the fire' at high speed.
(my fault for not checking the oil before he left).

Failing the above remedy it'll be time to test Ignition / coils.

 

Oil level on a 550 can be just above the top mark with a bubble showing and that's not too full. He may have experienced a stuck float.

I would have him open the drain screws and drain the carbs. New spark plugs was a good idea too.

 

Turns out it was rider error ... he was likely going WFO with the Choke ON at 80-85 mph. All that white smoke was raw fuel being vaporized, drowning the spark plugs. Funny how a bike will fight back under a heavy hand.