Motorcycle Forum / General / Yamaha / August 2004

i have an old flat track, fromm the 70's, i trying to restore he motor
first, it  has a dry sump oil system, my question is as follows, where
if any is there a check valve in the system that would control , or
draining of the oil from the reservoir down in the engine after it shut
down.  or refer me to someone who has experence working on them, the
problem is white oil type smoke after it sets a while, the valve giudes
and seals are good, compression is also good,  after it runs a mjnute or
two it clears up, it runs strong.                                 thanks
Gregory