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Discussion Starter · #1 ·
The picture below shows the old spark plug from my Morphous before I replaced it during my customizing work. Seems fouled to me. After riding the Morphous maybe 5 miles, I ran my finger around the outlet to my aftermarket, brand new exhaust and saw soot on my finger. Seems like it's running rich. But it's fuel injected. So assuming (hopefully) that I don't need to rebuild or replace my engine, how would you fix this? It runs fine though.

Household hardware Gas Auto part Engineering Fastener
 

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The picture's not very good but it looks like the gap is closed up for starters.

Was the bike fully warmed up, preferably driven a while before you pulled the plug? I'm not saying pull the plug with the engine hot, just don't start cold, idle a few minutes then pull the plug.
Ideally take the bike for a good ride, park it without excessive idling and let it cool down, then pull the plug for inspection.

If it was started and run just a few minutes it will look rich since it was running under cold engine enrichment. Even idling a warm engine for a while may lead to a dark plug.
 

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Discussion Starter · #4 ·
Thanks for those suggestions. I added some fuel injector cleaner and from what little riding I've done since then there seems to be less soot deposit on the end of my muffler. I may try a hotter plug.
 
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