Exhaust smoke -79

[xlfan]

Excessive exhaust smoke, tends to lessen when engine gets hotter. -79 1000 XL. I guess sumping can cause this? Would one culprit be oil pump check valve?  Is it possible for worn piston rings and/or worn valves/valve guides to smoke less after engine gets hotter? Maybe due to xpansion? Anyone experienced this kind of smoking?

xlfan

[pappyfreebird]

thats a good ?  xmayun....seems itd be oil in the pipes that smokes as heats then dries (that sound like what ya mean)..has that aon a few jap bikes ive bought n sold..there valve stem arears have a lil dip n would stsy filled (thats way desinged helps dry starts) n would be seal..but on a hog engine,,again good ?  sumpin she should jus puke it,,is it mo so on idle n lettin off er when in the power..to me power is rings idle is guides er seal,,all the time mmmm good ? sarry i ain no fuggan help at all am i..be innerestin ta see the end result  paps..this ol 76 i have will puff on let off er idle when jus warmin up,,but after warm then she clean up ..no seals in a 76 thou

[wreck74]

Smoke at start up then going away = valve stem seals or badly worn valve guides. Smokeing alot at start up then subsideing to a light smoke is Rings and valve guides/seals. It's easy to tell with a leak down test or a teaspoon of oil in the cylinder trick.

[olpigiron]

                 Something Comes To Mind,
If Your Going Down A Incline, Back The Throttle All The Way Off,
             Let The Bike Coast For A Ways,
          Then Crack the Throttle Open Again,
   If It Smokes, It Is Your Top End (valve guides,Seals).
I Can't Remember Where I Heard This?   Hope It Helps!!!

[pappyfreebird]

high vacuem smoke is valve guides seals er all..puffin whilst on her is blow by rings er score

[xlfan]

Thanks guys 
It sounds that I can rule out oil pump problems.
I'll try and get some more info about the engine, but it is sadly out of the bike so I have missed the possibility of running it to see for myself.

xlfan