There is very little of the cylinder left with no port of some kind in those engines. Normal full power is 5,500 RPM.

Every stroke is a power stroke.

 

I don't think a bridge in the rotor housing would be in more danger than the rather brittle cast iron bridge in a bridge ported side port engine.

 

Lynn E. Hanover 

Lynn,

   Sometime I'll show you one of the Yamaha GP 500cc road race cylinders I have. I wondered how they could have compression at first glance since there are SO MANY HOLES in that cylinder. Highest specific output of any normally aspirated engine on the planet. Hondas 500 was the most powerful with Yamaha close behind. Mick Doohan, was once asked how much power his Honda made. He replied, "My contract with Honda prohibits my telling. But I'll say that if they made 1 liter engine it would make over 400 HP!" No bridges in any of those ports.

 If you run the 3rd gen 2mm seals you shouldn't need a bridge. My concern would be if the bridge caused a wear pattern that might cause a stress riser right in the middle of the seal. This would be bad. Doesn't translate exactly to a piston ring.

Bill Jepson