I have a 76 fxe wiseco 30 over pistons and the heads and valves are in good shape will be file for weeks but every now and again when it starts it will blow a large cloud of blue smoke out the exhaust then it will be fine for a few more weeks didn't know if there were any ideas out there
thanks
Ron

 

Usually smoke at start up is valve guide/seals.

 

agree a valve guide seal could be loose on the guide top and sometimes it sticks up and that will allow oil to pass intake or exhaust /< my guess its an exhaust you should be able to pick it up on the plug what one is doing it

 

it uses no oil to speak of and it only does it once every 2 or 3 weeks or if it sits after being run hard , I guess I will have to pull it apart this winter