Hello! I know Scotty's main channel is all about cars, but I also know he knows about motorcycles too!
I ride a carburated 2004 Harley Davidson Sportster 883 with 13,000 miles. When I rev the engine in a lower gear between 1-3 (also in neutral), the engine occassionally makes a popping sound. The popping doesn't take place in the exhaust. It happen in the engine, I can feel it between my thighs when it happens. Also, very rarely, when I am riding, the bike will randomly lose power for a millisecond. Almost like a house flickering in a storm. The speedometer will flick from zero all the way back to my current speed when this happens and the engine light will appear on. Besides these two issues, the bike runs great.
Here's brief history of the bike:
I bought the bike back in August. I bought it from a used car dealer. They told me that they bought it from an auction outta state. It looks as though the previous owner (not the dealer) didn't take care of it. It looks like the bike sat outside for a while not getting ridden. Theres some rust forming on the bolts to the air filter cover, fuses are corroded. I haven't checked spark plugs or the air filter since I bought it. I checked the battery and it looks brand new.
What could be causing the popping engine?
Here's the unique thing about sportsters, the battery and tray are bolted to the oil tank, and that assembly is rubber mounted to the frame... so as you're driving around, the battery is always moving around relative to the driveline. This encourages the battery bolts to loosen up all the time, and also encourages cracks to form inside the battery cables where you can't see them... inside the shrink wrapped crimps of the cable. The speedometer and engine light are indicating that the bike is losing connection to the battery, and rebooting. Check your battery hardware first, if they are solid, then tug on both ends of both battery cables and see if one end doesn't pop off the cable. If the cables are good, then the ignition switch is the next suspect.
