Mechanic said he rebuilt the engine, smoke coming out of engine, could it be the grease burning off?

The mechanic said he rebuilt the engine to my 1974 Honda CB550 I bought from him. Said he rebuilt the engine and is in perfect running condition. He has many bikes lying around and seems as if he is a hobbyist for bikes.

He told me that he basically greased up a lot of parts of the motor and it is burning the grease off. The next oil change I do should remove the excess grease.

Assembly lube will burn off in a ride or two.

If it continues to smoke after a couple or rides then something is seriously wrong

Building motors in one of my strengths. Just amuse me, pull the spark plug(s) and see if they are oily wet. Just do it. If they are dry, it's what Ryde on told you. If they are black wet, call this guy and tell him it has issues and you want it looked at cause something's not rite. No motor that leaves my shop smokes, unless I don't wash the out side after the work. If the plug(s) are oily wet: it's a valve guide seal failure, or bad ring job. He should have installed new rings, with cross hatching 40-65 degrees.

More specific please

Be more specific.

Smoke coming out of exhaust?
Smoke coming out of crankcase breather?
Smoke coming off engine head/cylinders/actual pipe-mufflers from handling with greasy/oily hands?

Ask him if he used a can of Lubriplate on shafts, ring grooves, valve stems and seals. If he says he used only 1/2 the can because of small engine then OK. The use of assembly lubes is a known rebuilding drill for engines that might set on shelf awhile after building- this includes motorcycle engines in cold weather areas that get built in winter and even in summer- the mech has gotten into the habit of 'greasing' all the possible friction parts when putting them together for ease in breakin. - smoke is normal for awhile- but 100 miles is about the limit unless Harley- then 250 miles. Other mechs use lots of engine oil for assembly- still going to smoke at startup. Compression good, sprark plug not fouled, keep riding to 100 miles.

If it smokes after a hundred miles of riding he's full of chit. Poor piston ring job or too much slop in the cylinders for the rings to seal.

Even if he greased it up it should quit smoking a short time after the temperature comes up to normal. I would be very leery of his explanation.

After doing extensive work on the engine i'm sure any mechanic worth his salt would pressure wash the engine bay. There should be negligible fumes coming from that area