Motorcycle Repair: Hesitation on 1985 Honda Shadow 500, long term storage, gas additives

Question
I recently bought a used Shadow 500.  I noticed allot of hesitation when accelerating.  I opened up the air filter, and noticed a nest.  I cleaned out the filter as best I could, and ordered a new filter for it (still waiting).  It ran well after I cleaned it.  Then it sat for 3 days.  When I took it out again, it started to hesitate again the same way as before.  I checked the filter, it was pretty clean.  At a certain throttle position, it does take off normally, but if I take my hand off the throttle, it hesitates.  My question is, could it still be the air filter?  or maybe the carb?  Can I use FI carb cleaner on a motorcycle?  What other reasons are their if there is hesitation.  

Answer
Hi Anthony,

If a nest was in the airbox, that's evidence the MC was stored awhile. The fuel in the float bowls has varnished.

I suspect the pilot circuits and passageways inside the carburetors are partially obstructed and causing the problems. If so, the carbs will need partially disassembled and thoroughly cleaned to restore proper performance. Synchronize after cleaning.

Avoid using gas additives such as FI cleaners. These products may damage MC carb parts.

I recommend the following products for long term storage:  "Sea Foam" "Marvel Mystery Oil" and "Sta-Bil."

Unfortunately, there's no liquid-plumber for cleaning the carbs. If anything, try Sea Foam and see if the throttle improves. With any product, follow label directions to the letter.

I would have returned carb cleaning information to you, but there was no email address with your question as requested.

Respectfully,
Mark Shively