my engine is a 118 HP HTTC CNC ported and i installed valves Doherty Machine into the air vents of the heads engine.

the problem is that, when i open wide full throttle in fifth gear, at about 230 km / h, there is an oil leak from vents. Why?

I tried to enlarge the bolt holes screwed in the heads of the engine but can not figure out what the problem is.

can you help me?

 

From a Donny Petersen book:

 

I have a Joker Machine air cleaner. The banjo bolts create a channel so oil that comes out of the crankcase can be burned off in the intake. With high RPM's more oil comes out than can be burned off so the remaining oil leaks out the bottom of the air filter and sprays along the side of my motorcycle and my pants.

I think what you are experiencing is normal.

I have heard of some people lowering their oil level to help the issue but I just leave mine alone since it only happens at high RPM's. I also carry a rag with me to clean it up if it needs it.

 

My 12flhtk has had blow by problem after switching to a screaming eagle stage 2 kit. They told me it was normal, a $25000.00 machine puking oil? Taking bike to Throttle city to get the problem fixed. Dealers had NO idea what was causing it but after warrantee was out they all said it probably was the crank and they would replace it on my dime, don't think so.

 

thank you all for the information. I improved the situation by enlarging the bolt holes of 1 mm (now have the hole 5.5 mm = 0,21").
probably this powerful engine creates great pressures that need an outlet more big