we had a similar issue on a m 50 changed fuel pump no go changed sensor and fuel relayBare with me as I try to explain and get advise
My father in law recently purchased a 2005 C50 Boulevard from an older gentleman for $3,000. The bike has a little over 12,000 miles it and has a Cobra Exhaust. When we showed up to test ride the bike it was running a little rough and we were told it had been sitting for about a year in his garage. As the bike warmed up it ran better but still had some hesitation and felt like it was cutting out upon heavy throttle. We decided to pick it up thinking some fresh fuel and a quick service would fix it. We ended up changing the oil, air filter ,fuel and ran some injector cleaner through it and it didn't help much. After that wee decided to change the plugs (they looked good), and the bike still felt like it wanted to die upon snapping the throttle. If we slowly gave it throttle it was fine but heavy throttle she was choking out. I decided the next step was to pull the injectors and sure enough the injector closest to the battery was pretty dirty. After running them in my ultrasonic for about 10 cycles they are a lot cleaner. We installed them back on the bike but its still not running that great. Any suggestions? It runs a lot better but still feels like its a little rough.
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all the crap after 10 cycles of ultrasonic
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View attachment 40210 after cleaning injectors
had the wires at the coil really corroded on one side (different parts between L & R sides) 3 piece wire its a stupid setup but real easy to check at coil end for contamination changed coil and wires and all good