Take a look at your bike..do the pipes come STRAIGHT out? or are they ANGLED like the ones shown??
I am not saying they did not fit in the ports but doubt they were flat against the sealing surface.
Now look at the pipes shown in pic from the side, does there appear to be a 10 degree angle from the pipe were it exits head (up to first bend).. when you compare it to the lower (under the frame) section.