Honestly,.. I think your bike is fine, and I wouldn't worry at all...
Water in the muffler smells like oil, because it coming out of your muffler and it's dirty in there...
BTW... I would
never, ever go back to that motorcycle shop... Those guys a trying to screw you...
Yup...

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PS... where are located?... (it's good to put that in you personal info)..
There may be a site member that can take a look for you...
No shop should want $400 to $800 just to figure if you might have a problem...
Also,.. you don't have your gender stated,... are you female?... mechanics love to rip-off females... (no offense, either way)...

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