For a while now, my 1994 VN750 has had a problem maintaining idle after about 10 minutes of riding. Up until then, things are normal; then gradually, it's harder and harder to idle, until I have to rev to 3K or more to keep it from sputtering out at stop lights and stop signs. This is a problem, as to slow down for stopping I'd like to use my front brake, which is hard to do while also keeping my revs up by throttling. But if I park the bike for a while it's normal again the next time I start riding, but only for 10 minutes.
I tried seafoam, no good. I checked my airbox and battery, both are clean and working fine. The bike does not shudder or accelerate jerkily as would happen with dirty carbs (which I've experienced). So then, what?
Based on the symptoms people on this board and others have suggested it was likely to be a fuel intake problem based on something in the tank eventually clogging the petcock. Today I finally got around to taking the tank off and emptying the gas into a brand new plastic tub (with a drain spout) and it looked like this:
At first I thought that red/orange debris was leaves that had fallen into the tub from the trees overhead. Then I realized they're probably rust chips. Darn!
I poured the gas into a canister through a filter to catch this stuff, intending to refill my bike with this. But after removing my petcock and reinstalling it, it leaks fuel from somewhere. Darn #2!
The reason for this may be that I disassembled my petcock more than necessary. I was looking for a filter on my petcock like the diagram in the Clymers book shows it, and the BikeBandit parts schematic for the shutoff valve assembly -- something that looks like the fin on a submarine. But when I pulled my petcock out of the tank, it just had the two fuel lines, one long and one short (for the reserve setting). When I didn't find one, I continued disassembling the petcock and remove the diaphragm as well, perhaps tearing some kind of seal that is no longer tight. Rats!
So... now what? I can get a new petcock if necessary, but what do I do about the apparent rust in the tank?
P.S.: Is there an easier way to "drain the tank" than holding it upside down and pouring the gas into a tub out of the point of entry? It was kind of messy, and gasoline is not something I want to be messy with.