Topic: Thoughts on my old dream

[ken65]

Hi, im selling a 64 c72 dream. The compression is  a bit low and it blows a little bit of smoke that was with castrol 4T 15w-50..

Any how , when i  changed the oil to 30w(as par the manual) it appears not to smoke anymore. Is this even possible. PLEASE I,m not starting an oil thread

but am wondering if it's all my head. Thanks in advance, regards Ken

[calj737]

The only thought I'll risk is it's possible the heavier oil is creating more pressure on the seals in the head and thus forcing oil into the combustion chamber. If your results switching to a lighter weight oil have indeed reduced or eliminated the smoke from blow-by, then I'd draw that conclusion. Is it correct? Is it possible? Don't know for certain but there's a deductive logic to it. 

[chewbacca5000]

My guess is that the rings were slightly stuck to the piston and by running it the rings freed up and sealed better.  This happens all the time to a wide range of vehicles rings sticking to the piston due to varnish and carbon build up.  That is why alot of bikes that have not been run in awhile have that funky feeling to them.  As the rings free then they roar back to life.

[ken65]

Thanks for the insight fellas. Certainly food for thought. Much appreciated,

ken

[faux fiddy]

Certainly more testing is in order.