Please validate your needle. I believe 6DP5 does not exsist (no such thing). Neither Sudco nor Mikuni nor this site, http://www.psep.biz/store/mikuni_vm_type_parts.htm
show a 6dp5. Go to this site and get a 6DH3 and and a couple extra clips. When they go a flying, they're gone. While your at it, pick up a 159 Q2 needle jet. You just may find it useful.
The choke kit didn't work too good for me. The throttle adjusting screw is so easy to use. Once started, first or second kick always, push the choke back down, give the screw a little turn and at the first stop sign just turn it back.
Ker plunck Ker plunck Ker plunck Ker plunck Ker plunck Ker plunck Ker plunck Ker plunck 500 rpm all day.
By the way, I am the one that was using the 300 main on the 36mm VM on a 750. I use the 300 on my 34mmTM now. But that just me. You will find that their is no universal set up for these Mikuni's on a Norton(no two breathe identically, only similurely), but what's stated above should be concidered a starting point. The needle and needle jet setting is what sets these apart. When it's right, it's great.
Another interesting thing is once the needle and needle jet situation is cured, you can change the mains to your preference. As in 300+ for performance and 280 and below for economy. This may be unique to my machine, but I don't think so.
Rarely if ever will you need to be concerned about the pilot.
Better to be the one who understands than the one who needs to be understood.
I believe this philosophy to be a choice rather than a happenstance.