After fighting to get the 2000 400ex running I swapped Coils and bang it fired right up.. Smoking quite a bit though and was rebuilt prior to me taking it on trade and only couple hours max on it.. Valves were ticking pretty bad so I went ahead and readjusted valves to specs, they were way too loose.. Seems like some of the smoking went away but still does..

So I pulled the valve out of my compression gauge hose so I could put some air to it.. Lined all my timing marks up so I was TDC and put low air pressure 20psi, based on compressor regulator, and it definitely leaks out the exhaust..

So my question is with hearing the leaking air out the exhaust is that a Ring issue or Exhaust Valve seal issue?? If I rotate the engine thru the stroke and its off TDC you can hear it out the air box..

Thoughts?? I personally did not do the rebuild so can’t say for sure if rings were seated or installed correctly.. Doesn’t smoke like a chimney but still has more smoke than normal for 4 stroke.. Not so much at idle but when opening throttle..

Compression was 180 with throttle open and cold motor when I checked it earlier in week trying to figure out my problem why it wouldn’t start.. Ended up being weak coil..

John T