[clank]

Hi, starts good, idles pretty good, runs good at more open throttle. It's when the throttle is just open (less than 1/8) it sputters or misses no matter what gear. I have adapted my riding/throttle technique to avoid being embarrassed when riding past people. It's 59 Indian Chief, 30 pilot jet. It has HD mufflers and a stock air filter. When I set the points and timing I noticed I had rotated the distributor to it's max counterclockwise in effort to have the points just open at (what was it, 18 degrees?)BTDC. It seems like I need to turn it farther to be correct. I have the air screw around half to 1 turn out and it seems like I might still be a little lean. Question is, should I be looking at ignition or carb at this point. I can't seem to adjust either any further to get improvement. Thanks.

[High On Octane]

Sounds like the carb is too lean.  But you shouldn't have the points maxed at either end of the spectrum.  Might want to look into that more.

[clank]

carb is my best guess also, but I'll have the air screw all the way in if I keep going. Also tried to check for air leaks at the manifold. Maybe it's lean just because of the mufflers? As far as the timing, I will research if the distributor may have been positioned wrong when installed limiting the range of adjustment. Not sure if it works that way.

[High On Octane]

What exhaust are you running and what is the altitude where you ride??

[ace.cafe]

At 1/8 throttle, it could need a richer slide cutaway.

[clank]

Mufflers are HD 65380-90. I'm near Toronto, I don't know what the altitude is but sometimes I feel pretty high. I would say the sputter or misfire is at less than 1/8 throttle.
The spark plugs are brown. Tonight it was running worse and even let out a wheeze and stalled. Could it be weak spark? Could I need to advance the spark farther (I can't it's as far as it goes).

[High On Octane]

Is that an Amal 389 on there?

[clank]

Yes, a 389.  Problem solved. I blasted contact cleaner up the passage for the pilot jet and it has solved the sputter when first crack open of the throttle. Along the way I also found fuel tap (petcock) partially blocked and a very loose connector on the HT wire.