I have a 1980 CB900C that the previous owner rebuilt the carbs on. I just recently got the bike running correctly at idle (the carbs weren't seated into the boots properly, a coil was cracked so I got dyna coils, and I got new CDIs) and took the bike for a 5-10 minute test ride. That's where I found out that the bike breaks up badly above 5k rpm. It doesn't matter if I am riding the bike or just revving it up while it's sitting. I pulled the plugs today and 1&2 and rich and 3&4 are lean. What would be causing this? I've attached a picture of the plugs.
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