What am I to make of the dicoloration on my V&H heat shields?

[FrameMount1200]

Originally Posted by Tomcatt

Then pull the carb, take off the float bowl and see what size pilot jet is in there. If it's a 42 you've found the likely cause. Replace it with a 45 and set the idle mixture screw at 3 turns out.

I haven't taken the float bowl down yet, but I just checked the idle mixture screw and it was at 1.5 turns out. I'll turn it out further and see if things improve.

I did have a couple of pops back through the carb yesterday, but I don't honestly remember if the bike was fully warmed up when it happened. Could have just been cold, could be this setting, or could be a weak accelerator pump, although maybe not that because it doesn't show consistent signs of hesitating on acceleration.

I'm also getting a little deceleration popping which I understand is another sign of not getting enough fuel when the throttle has been cut.

I put new plugs in yesterday, so I'll be able to read those after a while.

Background to all this is the fact I'm still learning what the bike wants as it warms up. It's sill in the 30's and 40's here too.

.

[wedge]

Originally Posted by FrameMount1200

I haven't taken the float bowl down yet, but I just checked the idle mixture screw and it was at 1.5 turns out. I'll turn it out further and see if things improve.

I did have a couple of pops back through the carb yesterday, but I don't honestly remember if the bike was fully warmed up when it happened. Could have just been cold, could be this setting, or could be a weak accelerator pump, although maybe not that because it doesn't show consistent signs of hesitating on acceleration.

I'm also getting a little deceleration popping which I understand is another sign of not getting enough fuel when the throttle has been cut.

I put new plugs in yesterday, so I'll be able to read those after a while.

Background to all this is the fact I'm still learning what the bike wants as it warms up. It's sill in the 30's and 40's here too.

.

When you cut the throttle you cut the air, so it tends to run rich.

[FrameMount1200]

Originally Posted by wedge

When you cut the throttle you cut the air, so it tends to run rich.

According to these guys at DK Customs, deceleration popping is a symptom of too lean. But maybe they're only referring to FI engines.

https://youtu.be/iu8RVJdiEu4