Join Date: Jan 2016
Year/Make/Model: 2007 Vulcan Classic
Classic, surging / stalling at low rpm
I just purchased a 2007 classic 1600 with 4700 miles. In understood that it may have been sitting for a bit. She is immaculate through and through. When I was initially looking, it would start right up - but stall the second you tried to give it gas. The light was on and it had no bars - so that seemed to be the reason.
I buy the machine and go to pick it up the next day. The dealer assures me once it was topped off everything was tested and it ran perfect. I pick it up and start my drive home.....
At 10-15 mph in 1st, 25-30 in second - even at like 50-60 in fifth, (every gear at that specific rpm range) she wants to do one of two things. Buck like a bronco or stall. I can power through it and get to a higher rpm, sometimes easier than others. Sometimes I have to pull in the couch and rev her up and keep her in that gear and try and get through it - especially in first with a slow acceleration from stop.
If I shift swiftly from gear to gear I can get past the problem and it seems like all is good, but it's not.
It's almost impossible to "cruise" at low rpm. It almost requires a constant acceleration, or a cruise at a much higher rpm (where I think you should shift)
They filled I half way with gas, so my first thought was to top off with high test 93. Same issue prevailed. I then added Lucas Fuel Injector/ Deep Clean. Same issue - albeit only drive for 5 miles after that because it's dark now and at some speeds this is borderline dangerous.
I get home and I check the air cleaner, because it seems like it's choking a bit. I almost feel like it's doing what a carbureted bike would do if you jumped on it cold and tried to ride at low rpms....
I open both side up and it looks factory new. The entire bike does. Again, it only has 4700 miles.
Here are my ideas moving forward, because it seems almost unbridgeable at the point.
Spark plugs ? Which ones, are there any special considerations, and are they pre gapped?
Clean the TB, and even spray some sea foam in there and rev her up to see if that can burn off some old carbon deposits, etc
Run this tank through and see if that Lucas makes a difference, or if the bike works itself out from being run a bit.
Also, as this may be a give away - if I have it parked, running in neutral, and rev it up say, 800 rpm, it will have a constant, in perfect rhythm, fluctuation. This fluctuation will be constant as long as I hold the throttle at that exact spot and probably has a 300 rpm sway.
In addition, when I park the bike and turn her off I hear the sound a balloon would make if you never tied it me had the air Coke out the bottom slowly. It sounded electric but I realized if I opened the gas tank it went away. Close it, and not even starting the bike again, it would start to do that again, I opened the cap. Instantly gone. Then I closed I and it eventually stopped.
I thought to try the "rev up thing" with the cap open to see if it still fluctuated, but I didn't want to make my neighbors mad at night. I'll wait for day time to start her up.
Thank you for your time guys. I appreciate all help in advance.