Running lean or not?

I just installed HardKrome Strippers on my 07VN900C. The idle hasn't changed and I only experience an occasional (rare) pop on deceleration. It occurs more often if I ride before the 5? minute warm up process is complete. The bike runs great, but I'm concerned about it maybe being lean and damaging the valves (or whatever else). If it runs OK and doesn't pop, should I feel OK with it? I don't want to invest in a PCIII since I have no intention of messing with the air intake. How can I check for a possible lean condition??
Thanks