So did you run it with stock jets? How long? X-2 on carb clean and fuel. Other than unported 4mil and lower elevation I'm starting in 300-320 range with same pipes when I put them on.
What you should do is degree your drag jugs with stock stroke then with 4mil. That right there will educate you a lot. X-2 on Jennings, also H. Gramm Bell's book. Some to be learned on McDizzy. Even tho some down Jennings because it's 1970 tech, guess what, there's not much else available ! Been informed on here that if you contact the pipe manufacturer that they will tell you good range of ex timings for their pipe , don't know tho. Buy a bunch of gaskets and go to work. Just remember that at exhaust opening a little bit can be several degrees of timing. You can always take it out but cant put it back .
Arrow on arm is under your thumb , arrow on case is on hump by sprocket,. Back screw off, hold arm with arrows, snug screw, back off 1/8 - 1/4 turn , hold screw with screwdriver , tighten nut. By snug, finger tite/barely touching.
Throttle Override Retarded Shit . Prevents runaway if throttle sticks, only problem is that they malfunction, when nothing is wrong. . Limits spark advance, sometimes limits it to no spark at all.
BB will crack boots. I thought it was myth untill I looked closely at my son's. I used some plugs from hardware, three bond , clamps. No crossover, runs fine.
Also consider the fact that water boils at a higher temp under pressure than at atmospheric pressure. The cap you have now might not be building any pressure, things do wear out.
My son's banshee has exactly what Mike is showing you. If you needed a crank and a bore it's an economical way to go. Increases it to about 380-385cc.
I wouldn't have known unless I had to tear it down because he flipped it into a mud hole . Granted you leave some power on the table by not porting for the stroker but you can always do it later. My son's still had stock pipes so he is still leaving a lot on the table. Also not ported either, but it runs good enough for him (for now, lol) . Let us know what you decide.
Sudco has a good book on carb tuning. The Clymers manual covers the carbs very good.
Nothing wrong with stock carbs, Isee a lot of builds with them. might look into getting them bored to 28mm. Remove tors properly.
Also pull 10mm plugs on side of cylinders to drain all. If you pull lid off you will have to change jetting. Even pulling snorkel will increase air to where you might have to change jetting.
There is such a thing as tuned intake tract length. Not sure if it affects reed valve engines the same as a piston port. Check your plugs. If you are running rich, it's having an adverse effect, if it is now running lean it may be actually be an improvement in air flow.
If you can somewhat duplicate conditions around home, try pulling choke out halfway. If it gets better your lean.
Highly unlikely anyone will do this to a new one. After you get everything to work THEN you make it pretty. Have you never seen a Banshee brought back from the dead? They can be up to 24 years old!!
Pull clutch cover, bet something is up with kicker idle gear. Other possibility is bearing on trans shaft.
Figured out you were riding, shut eng off, coast to stop