Probably a backfire. The pods are a place for the carbs to vent through. Basically the charcoal canister of the day.
Glad you got the cylinder running. You used me favorite high tech method of diagnostics.
06 Paul Smart Sport Classic NFS ever.
08 S4RS Tricolore #081 NFS ever.
01 M600, aka, The Pink Monster
72 Norton Commando 750
03 KX60 just rebuilt the entire engine, with M600 rear shock, no wait now with S4RS rear shock...
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