John, I have some BSA heads with big inlet valves but I also enlarged the exhausts. If I have new seats fitted I could use std 35.8mm or 37mm with the 44.5 inlets. I'm wondering if it makes much difference, most are 38 or 39mm. They go fine but I'm wondering if they are detrimental?
Joe do you have pictures of the intakes?
I welded “fillets” in my exhaust pipe on the A65, it worked well and gave a better top speed and more seat of the pants feel at midrange torque
. However the fillet took up about 1/6 of the port area and it made carburettor tuning a right royal pain in the ass, so I got my die grinder and removed them again. I was having to use leaner slides #4, standard needles at lowest setting and 105 needle Jets. The difference was definitely noticeable Straight away after I removed thee fillet, even after I rejected the carbs to suit its new requirement. I’ve since modified my silencer again so it needs some more tweaking, but top end speed is still not quite as good.