Rough Idle HELP!!!!!!!

[des max]

ok guys i ve posted a few times before on here about this problem and ive done everything i have read on here. (get to that in a sec) i have a 2000 vmax stock except delkevic slip ons. whats happening is after the bike gets warm and everything is on ie turn signal, fan, high beam, etc the bike starts to idle really rough and eventually dies now it will start right back up but will only stay running if i can lighten the electrical load. now i have replaced the stator and the r/r and ran the wires directly from stator to r/r and from r/r to battery. i am at my wits end here i dont know what else to do to fix this ive checked all grounds and connections ive had the battery load tested. i just dont know what else i can do. it does have a switch for the fan installed by the PO which i checked and looks good it is wired into the wires that are connected to the factory fan switch. the only other useful thing i can think of is that i found this problem while running the bike sitting while adjusting the mixture screws to get rid of the back fire i had. please help guys i dont know any other electrical part that could be doin this im pretty sure it is electrical as ive gotten it do this multiple time by letting it warm up and turning everything on. ps i know this isnt the electrical section but i was hoping to get as many eyes on this as possible. sorry for the long post. unfortunately this has made me consider selling this bike. Which sucks because this is the only bike i have ever wanted. thanks for your help guys

Jared

 

[Dragmaxster]

Probably the battery.
If you think it is electrical do you have a multimeter?
If you rev at idle is there a change in the battery volts?

 

[des max]

yeah I've checked the volts when it's off the volts read fine at 2500 rpm they read fine at 1000 rpm idle they fall into the barely charging category.

 

[Traumahawk]

What is the volts with it idling....hot with the fan going?

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[des max]

ok so with a volt meter on there a full electrical load ( hi beam fan on turn signal on) knocks the voltage down from 12.9 to 12.3/.2 the fan alone knocks it down .4 volts the hi beam and turn signal are responsible for .2 combined

 

[ga_max]

Just tested my 94, fan on, high beam on, turn signal flashing, 13.1 volts at idle. (after a 60 mile ride)

 

[Traumahawk]

ok so with a volt meter on there a full electrical load ( hi beam fan on turn signal on) knocks the voltage down from 12.9 to 12.3/.2 the fan alone knocks it down .4 volts the hi beam and turn signal are responsible for .2 combined

If the volts are dropping too low....it won't give enough juice for the tci to fire effectively. It can cause the bike to run rough....or even stall. What happens when the bike idles at 1100 rpm? I also wonder if the grounds need to be cleaned?

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[Miles Long]

Desmax-
Re your first post, you say "once the bike gets warm"....then the low voltage problems begin.
Try this. Fully charge the battery overnight (should read at least 12.8, if an AGM), then have your meter hooked to the battery as soon as you start the bike, with full load applied, including the fan via the override switch. Record the initial voltage at idle, don't work the throttle, record the voltage as it drops, noting the elapsed time before the bike begins to stumble due to low voltage.
To troubleshoot, first try cooling the RR with a hand-held fan after starting the cold bike. Continue cooling as the bike warms up, see if this alleviates the problem.
Stators can sometimes fail as they heat up, due to insulation breakdown. Resistance and leg short testing can be done cold and hot, if you have retained the original three-part connector, OR changed to individual butt connectors. If the RR is O.K., this may be your problem.
All this is assuming that all connections are good, and the battery is in a good state of health.
As for your RR wiring changes - another option is to Y-joint the red positive wire, with one wire going to the + battery post(with an in-line 30 amp fuse), and the other wire fed to the original wire, going to the infamous "crimp" connection.
The negative RR wire can also be Y-jointed as well, with the extra wire going to a good ground on the l.h.s. of the bike.
I did this to my bike, and gained an extra half volt over the full rev range.
Cheers!

 

[des max]

hey TH are there any grounds in particular your thinkin of as I have checked all the ones I could find also are you suggesting I should set the idle at 1100 permanently?

 

[des max]

hey miles thanks for the response I have just recently replaced both the stator and r/r the r/r is a MOSFET off of a zx10 and mounted under the passenger seat I had my hand on it when it started to idle rough and it was warm but not even close to being to hot to touch or anything I am almost wondering if my new stator is junk? thanks for your help I appreciate it

 

[Miles Long]

hey miles thanks for the response I have just recently replaced both the stator and r/r the r/r is a MOSFET off of a zx10 and mounted under the passenger seat I had my hand on it when it started to idle rough and it was warm but not even close to being to hot to touch or anything I am almost wondering if my new stator is junk? thanks for your help I appreciate it

Then check the stator for resistance and ground faults AFTER it has warmed up!

 

[Traumahawk]

hey TH are there any grounds in particular your thinkin of as I have checked all the ones I could find also are you suggesting I should set the idle at 1100 permanently?

The earlier Vmaxs had an idle around 1000 and the later ones at 1100. The higher idle might help with the charging. Also if you've checked all of the grounds that you could find....you probably got all of them.

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