Ruff idle after 25 miles at a stop light.

[jagco1]

I was out yesterday ride around the 25 miles mark at a stop light - bike started running choppy almost cutting off. I made it back home but every time I came to a stop I had to kinda rev the motor a little to keep it running at idle.

When got home check the voltage at the motor running 12.2 to 12.7 volts at idle.

Today I charge the battery, ran the bike at idle motor cool volts at 14.3 when I turn on my head lights the volts drop to about 13.6. When I turn the head light off volts would claim back to 14.2. I let the bike run until the fan kick in motor hot now. As the motor started getting hot volts went from 14 down to 13.3 when I turn the head light on volts drop to 12.6. When I rev the motor up to 3000 rpms volts will go to 13.8 to 14.1. I check ground wiring plugs, fuses,
My r/r has the ground wire built in.

Like to have your inputs what you all think... I'm thinking R/R bad but not sure. I may have miss something to check. Check stator black plug wiring clean.

I let the bike sit for 30min not running battery volts 13.3.

 

[alorio1]

Do away with the 3 wire connector from R/R and run the red wire straight to the battery (fused). Here is a good write up on how to get your voltage up...http://www.vmaxforum.net/showthread.php?t=19108

 

[dannymax]

+1 to Joe's post.

You have the finned RR, not the smooth one, right?

Snip the red & black RR wires on the RR side of the plastic connectors, solder in jumper wires no smaller than the oem wire gauge and go directly to the battery terminals....put a 30A in line fuse in the + wire also.

I was going to eliminate the connector on the 3 white stator wires but changed my mind after the results I got.

 

[Redbone]

I'm running a new setup from Eastern Beaver for the stator wires which has connector to match the one from the stator and a sealed connector at the R/R. EB also makes a sealed connector for the pos and neg connectors to which I'm running new 12 ga wires directly to battery with a inline 30 amp fuse for the pos wire. My new R/R is a R1 style finned mofset type rectifier. I'm mounting it in the LH scoop in place of the vboost controller and round connector.

 

[Hellboy]

I wouldn't think that a low charge rate would cause a rough idle? It sounds like maybe junk in the carbs getting stirred up or partially blocking fuel which isn't as noticeable with higher rpm. My charging problem just lead to difficult starting after I would stop on a ride, always ran well once started.
agree with alorio1.
I bypassed the 3 wire connector and went straight to the battery, charging problem solved. Just that simple, Hope it is for you.

 

[jfeagins]

The CDI box likes GOOD voltage, especially as it ages, in order to provide adequate spark on all cylinders. When everything isn't perfect, and the fan kicks on, and voltage drops, the CDI will begin doing weird chit, including errant spark where no spark belongs, evident by sparks jumping from a plug wire directly onto a valve cover, leading a person to think they have bad plugs, bad wires, bad caps, or even bad coils. As this happens, the bike is missing on one, or more, cylinders and therefore running rough at idle. As you increase throttle, if the bike hasn't died, and as rpms increase, voltage will often go back up just barely enough so that the CDI becomes fully operational again and symptoms go away (usually by 2500 rpms or so).

All this is well documented on multiple threads here on the forum. The easiest, fastest, best cure is to get the charging system back into top shape, to ensure a good 13.25V, or better, at idle speed with the fan kicked on.

 

[Miles Long]

The CDI box likes GOOD voltage, especially as it ages, in order to provide adequate spark on all cylinders. When everything isn't perfect, and the fan kicks on, and voltage drops, the CDI will begin doing weird chit, including errant spark where no spark belongs, evident by sparks jumping from a plug wire directly onto a valve cover, leading a person to think they have bad plugs, bad wires, bad caps, or even bad coils. As this happens, the bike is missing on one, or more, cylinders and therefore running rough at idle. As you increase throttle, if the bike hasn't died, and as rpms increase, voltage will often go back up just barely enough so that the CDI becomes fully operational again and symptoms go away (usually by 2500 rpms or so).

All this is well documented on multiple threads here on the forum. The easiest, fastest, best cure is to get the charging system back into top shape, to ensure a good 13.25V, or better, at idle speed with the fan kicked on.

Mr.Eagins - I wonder if anyone has measured the input voltage at the CDI, and compared to battery voltage?
If there is a significant drop, do you think it possible to run a fused 12 ga. wire direct from the battery, to a SPDT rocker switch (replacing the existing engine stop switch), and using the extra output to feed the CDI?:ummm:
Cheers!

 

[wildweasel_pt]

Heres mine...

 

[sdt354]

I wouldn't think that a low charge rate would cause a rough idle? It sounds like maybe junk in the carbs getting stirred up or partially blocking fuel which isn't as noticeable with higher rpm. My charging problem just lead to difficult starting after I would stop on a ride, always ran well once started.
agree with alorio1.
I bypassed the 3 wire connector and went straight to the battery, charging problem solved. Just that simple, Hope it is for you.

It can cause a rough idle when hot, and is often the first sign of an electrical issue. . The three wire connector seems to be an issue on older bikes. High resistance/corrosion burns the plugs. I'm using twist lock connectors in place of the stator connector.

 

[jfeagins]

Mr.Eagins - I wonder if anyone has measured the input voltage at the CDI, and compared to battery voltage?
If there is a significant drop, do you think it possible to run a fused 12 ga. wire direct from the battery, to a SPDT rocker switch (replacing the existing engine stop switch), and using the extra output to feed the CDI?:ummm:
Cheers!

I'm sure there are several ways to patch the wiring to help out, but IMO I'd simply fix the R/R output to be correct to start out, and if there is someplace in the wiring preventing adequate voltage from arriving at the CDI, then fix that too, rather than than complicating the piss out of the wiring by running patches everywhere. But that's just me - I use bandaides sparingly, and usually only as a temp fix until proper repairs can be performed.

 

[jagco1]

Do away with the 3 wire connector from R/R and run the red wire straight to the battery (fused). Here is a good write up on how to get your voltage up...http://www.vmaxforum.net/showthread.php?t=19108

I had this ran all ready r/r to the battery and grounded, When the bike gets hot volts start dropping. This is something just started... When I turn on the head light volts will drop and not claim back up. If i hit the rear brake light to stop volts will drop.

 

[jagco1]

+1 to Joe's post.

You have the finned RR, not the smooth one, right?

Snip the red & black RR wires on the RR side of the plastic connectors, solder in jumper wires no smaller than the oem wire gauge and go directly to the battery terminals....put a 30A in line fuse in the + wire also.

I was going to eliminate the connector on the 3 white stator wires but changed my mind after the results I got.

Yes a vmax 2005 r/r I bought 2 years ago. I did the r/r red wire to the battery....

I did check my key switch took it apart to check wiring it's ok....

I'm off tomorrow I will check kick stand switch....

I will pull my head light apart to check behind the light....

Carbs are good no problem with them. Something electric is going on...

Funny Danny no my turn did you pass the bug over to me...

 

[Fire-medic]

Sounds like a bad ground to me, f you operate the brake light and things go wonky. Or a incipient/terminal (as-in 'terminal stage of its life') battery headed to recycling. Or both.

 

[dannymax]

Yes a vmax 2005 r/r I bought 2 years ago. I did the r/r red wire to the battery....

I did check my key switch took it apart to check wiring it's ok....

I'm off tomorrow I will check kick stand switch....

I will pull my head light apart to check behind the light....

Carbs are good no problem with them. Something electric is going on...

Funny Danny no my turn did you pass the bug over to me...

Well, I certainly didn't intend to but there sure does seem to be something 'going around'....ey? :bang head:

 

[alorio1]

If you don't find a bad ground it could be your stator shorting under load or your R/R is bad. The stator might check good doing a bench test, but under load it may be shorting. I'm not sure about electrical stuff, but I think Sean Morley will send you a R/R and a stator to get your problem fixed and then you pay him for the item that you keep and send the other part back.

 

[jagco1]

Sounds like a bad ground to me, f you operate the brake light and things go wonky. Or a incipient/terminal (as-in 'terminal stage of its life') battery headed to recycling. Or both.

battery volts after setting over night picture.

When the bike is cold at idle volts 14.3 when the bike runs warm up running about 15mins volts start to drop at idle slowly. It will drop to 12.3 when I rev the bike up volts go up to about 13.5 when I turn on the head or other lights volts will drop. Won't go up....

 

[Miles Long]

battery volts after setting over night picture.

When the bike is cold at idle volts 14.3 when the bike runs warm up running about 15mins volts start to drop at idle slowly. It will drop to 12.3 when I rev the bike up volts go up to about 13.5 when I turn on the head or other lights volts will drop. Won't go up....

I had exactly the same problem a few years ago.
Do the shorts to ground and stator resistance tests (as described in the Electrosport chart) when the bike is cold, then after it has warmed up, and showing the symptoms above.
This is the big advantage of not permanently connecting the stator-RR wires-you can test at any time.
Cheers!

 

[jagco1]

[/I]

I had exactly the same problem a few years ago.
Do the shorts to ground and stator resistance tests (as described in the Electrosport chart) when the bike is cold, then after it has warmed up, and showing the symptoms above.
This is the big advantage of not permanently connecting the stator-RR wires-you can test at any time.
Cheers!

What are the AC volts across the stator black wires and what rpms should it be to check. "O" to where is this chart - as described in the Electrosport chart I could not find it on there site.

 

[Miles Long]

What are the AC volts across the stator black wires and what rpms should it be to check. "O" to where is this chart - as described in the Electrosport chart I could not find it on there site.

Link to chart

http://www.electrosport.com/technica...ng-diagram.pdf

Go to the last page, paragraph beginning "stop the engine"
These are tests with the bike not running.
You have to disconnect the three wires coming from the stator to perform them.
As I said previously, do the tests with the bike cold, reconnect, start and warm up the bike till you see the voltage drop, shut the bike off, disconnect and do the tests again.
If everything checks out, you can go ahead and perform the running test for A.C voltage, as described after the above tests on the chart. Again, the three wires have to be disconnected to perform this test. What you are looking for is at least 50 volts A.C. across each combination of wires, at about 5000 rpm. The voltages should be approximately the same for each measurement.
BE CAREFUL DOING THIS TEST! SHOCKS ARE A DEFINITE HAZARD!
Again like I already mentioned, my bike was showing the same symptoms as yours. I performed all the tests on the Electrosport chart, everything checked out O.K. What I didn't do is believe the last line of the chart.....
which says "if everything is O.K, problem must be a bad battery"
So I replaced the stator, which didn't solve the problem. Then I replaced the battery, and everything became normal.
The good part about this is that I put in a aftermarket stator that puts out more watts than the O.E.M., and managed to tighten the three starter clutch bolts, that were beginning to loosen up.
Good luck, and.......Cheers!

 

[jagco1]

I was able to work on the bike some today.... I went through a lot of the wiring everything seem good.

I pulled the r/r white wires out of the black plug and the bike run off the battery.
I check voltage at the stator black plug wiring - I'm getting 72 AC volts at 5000 rpms if I go up higher it will hit AC 80 to 84 6000 rpm is this to high..... At 4000 rpms volts 60..... r/r gets hot I rev it to 6500rpm it hit 85 volts ......

Volts DC start dropping down to 12.4 from 14.2 volts when motor gets hot...

I'm thinking stator is putting to much voltage.... I check all through the black wiring with the voltage probe.

AC volts at idle at the stator wiring...

I check my r/r for AC voltage at the battery no AC volts going through.... only DC volts...

So I'm thinking stator putting out to much volts AC...
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