2003 low mileage VFR bogging down

[FtFirst]

Howdy,  Last year I sold my 2003 VFR with very low mileage to my adult (40's) son who uses it for his daily commute.   He is reporting some problems with it bogging down on the commute.   I really liked that bike, just got a bit old for it, and never had any issues with it - even on a nice 1500 mile summer tour.   I'd like to help him solve his problem, so here is the description.   "The bike is bogging randomly at all speeds. Not fun attempting to pass a car and having the acceleration cut off.   No rhyme, no reason. Tried different gas, seafoam additive, running it hard, running it soft. Randomly, independent of weather or temps, the engine will stutter/bog and decelerate. If I pull in the clutch the engine continues with the problem. If I let off the gas or accelerate hard it disappears."      Any thoughts on where to begin running this down would be most welcome.   Thanks very much. 

Dave

 

[Polarbear]

I am not an expert by any means, but it sounds electrical to me. I would check the following:

1. connections at the battery; male sure everything is tight

2. grounds; check all grounds... (to me, this is the biggest suspect)

3. all connectors to and from the stator and R/R

4. the battery itself, have it tested, one never knows... 

 

Best of luck. 

 

C

[Knight]

Check the air box for a rodent nest. Maybe his area has more homeless mice?

 

Has he done any maintenance to the bike? You may want to list items here.

 

If the tank has been up, then the vent hoses may be at risk of getting crushed from being out of position and now generating vacuum that holds the fuel back. Although the fact that it recovers without opening the tank makes me think this is not it.

[FtFirst]

Thanks Polarbear and Knight,   Will follow up on your suggestions.

Dave