Just recently the idle on my f4i just started jumping around....over this weekend and is hopping around usually in the range of 2000 to 3000 rpms but have seen it act up over that before.....anyone have any of the same trouble?

 

check for any vacuum leaks, a line could have came off or developed a leak, but normally this means a vacuum leak somewhere. hopes this helps

 

turtle i think its time to let the old f4i go....u need some new freshness

 

Check vacuum lines.. Make sure your plugs are good. And synch your throttle bodies.

 

haha i knew you'd say throttle body sync....i'll take my tank off tonight and check all the lines and all that fun stuff.....thanks JB

 

give me something new then, hahaha.....if i didn't have so many extra f4i parts i'd consider it

 

While you have the tank off, make sure the intake boots connecting the TB's to the head are seated and tight.

I've seen quite a few lately that were loose. Loose intake boots will also cause a vacuum leak and cause an erratic idle.

 

i will check that as well, thanks

 

Make sure your battery is good too, everytime I have a dead battery my **** ***** up

 

Hopefully its not the fuel pressure regulator

 

ill sell you my 636 for lets say uhh.....9500 cuz were friends. anyone else id need 11000

 

Im going through the same thing but mine hesitates off idle and my idle is garbage.
causes....
1. vacuum lines unplugged, cut or clogged.
2. bad fuel pump (check pressure)
3. bad fuel pressure regulator: run bike then pull vacuum side off regulator. If you see fuel coming out the regulator vacuum side, its toast. Another way is to replace the vacuum hose coming off the regulator and make it clear hose. Run the motor, rev it up a few times, if you see fuel in the vac (clear) hose the regulator is toast. My understanding is that if the regulator is bad it would allow fuel to pass by the diaphram, in the regulator, out the vacuum lines, straight into #2 and #3 cylinders floading them.
4. throttle bodies not on completely.
5. badly needed TB sync