This is getting good 
What exactly are you doing with those intake "pockets"? Hard to tell from the pics.
Spence
Hi Spence,
So I was reading Hondaman's FAQ and he spoke about the flow of the heads in the 550. Here is the link
http://forums.sohc4.net/index.php/topic,7401.0.html. So specifically in the section he wrote:
3. In the heads: all of the inline fours except the 400-4 had breathing issues. Grinding a "pocket" above the intake valve(s) and matching the ports to the carb tubes will improve them, especially at high RPM. Polishing the intake valve(s) helps, too. Don't back-cut the intake valves or you'll pop off a valve head - an expensive day, at best. (Backcutting exhaust valves will make them burn, and quickly - the CB650 malady). Trim (narrow) the intake valve guide bosses for a smaller profile, and polish it. Smooth, but don't polish, the intake tract. If you're good at heliarcing, raise a bead about .100" high along the bottom of the intake ports (CB750 only) in a half-moon shape, then smooth it off along the sides so it "restricts" (apparently) the bottom passageway about 1/3 of the way around. The floor of the port should ramp up to it, then be fairly abrupt in fall-off on the valve side. Do this at the point where the intake track bends down toward the valve (no, it's not easy). Although not obvious, this mod creates some "free turbocharging" at RPM above 6000, all the way to 16000 (lots of work), which deals more with fluid dynamics than I will put into this post.So initially I am just doing a big bore on the engine. I will probably put it all together and just run it this summer as is. Then this next winter I am going to build the top end out quite a bit more with cam, valves, rockers, springs, etc. But to build up to all this I am trying to get the porting on the head done now to help with the response because I would like to track the bike this summer some. I am going to try and get dynos done at each stage too since I dont see many actual numbers and have the opportunity to do it.
Ernie
