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Discussion Starter #1
It always seems like whenever I fix one issue, another issue rears it's ugly head. :BLAM:

Over the last week or so I've noticed when riding at night my lights are quickly getting very bright - independent of my actual RPM. My headlight gets nearly as bright as when I have the highbeam on (and the ACTUAL highbeam is obnoxiously bright!), my instrument cluster brightens, even the turn signals and the indicator lights on the dash are overly bright.

If I remain at a constant RPM it'll eventually go away, but it does not seem to be tied to the RPM at all. If I rev the engine when the lights are bright I don't really see a difference, and if I lower my RPM (pulling the clutch in), same thing.. it doesn't get dimmer.

It's very unsteady and doesn't occur all the time. I'm more concerned that it's gonna burn out my bulbs prematurely. Any ideas?
 

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Discussion Starter #3
What's the best way to check? Just check the voltage levels coming out of it?
 

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Yeah it should be 14+ when above 3000 RPM. Use a meter and give it gas and hold at about 3500. If you see the voltage fluctuating at an even speed, that would tell me that it is time to replace.
 

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..have a vulcan good day!
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Check/Clean the 3 Stator (AC) connections as well as completely cleaning R/R connection.

:smiley_th
 

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Discussion Starter #6
Alright, here's the latest update...

A few months back I had already removed the bullet connectors and soldered the connections. I double checked them today and everything looks good.

I checked the voltages coming out of the R/R, I'm getting 13.5v at idle, 13.56v at 3500rpm. However I don't ever see the lights brighten while sitting at idle or even while revving the engine..it seems to only happen when riding, which is odd.

I did re-locate my R/R this evening, didn't have a drillbit long enough so I had to remove the battery box. Overall a hassle, but not a big deal. R/R was moved to the usual spot folks seem to mount it at. I took her for a ride after hooking everything up and noticed everything was brighter about 80% of the time.

I thought to rev the engine a bit to see if it was tied to RPM and a strange new symptom occurred.. In gear (3rd or 4th) I pulled in the clutch and revved the engine. The RPM needle went haywire - up down up down, going as low as 0 RPM and up to 4-5k RPM and back down a few times a second. The engine itself just sounded odd, almost like a car engine that has an RPM cap on it when being revved, but not quite.

The electrical seemed to flicker while this was going on as well. I also tried giving it a lot of throttle with the clutch out and in 3rd/4th..same thing happened which scared the **** out of me (felt like I was gonna lose control) so I didn't do that again.

I'm completely stumped. It sounds like my voltages are a bit low coming out of the R/R, but I was thinking that's just my stator? I've been planning to replace that in the fall when I pull the engine. Could a bad R/R cause this new symptom as well?

Any suggestions on safely checking the voltage while riding?
 

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Discussion Starter #9
Gonna try that later..it's alright to wire it up to the battery and not the R/R? I guess it shouldn't matter, but double checking.

If that's the case, I can probably rig it up to the battery tender leads I have coming off the battery.
 

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Discussion Starter #11
Can you explain that a bit more? For now I'm just rigging my cheap multi-meter up, but going forward (considering the issues I've had), I'd like something a bit more permanent eventually.
 

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..have a vulcan good day!
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Can you explain that a bit more? For now I'm just rigging my cheap multi-meter up, but going forward (considering the issues I've had), I'd like something a bit more permanent eventually.
I have installed the Ignition Coil Mod...a relay(available at most automotive stores) which supplies +12volts directly from the battery onto the Ignition Coils (hence +14 volts at 5K rpm)....the relay is triggered via rear coil 12v (red ?) lead which is switched on/off via the Ignition Switch (EDIT: relay will operate properly on 7-16 volts). The front coil harness 12v lead is taped off.
(meter ON only when Ignition ON). I mounted the Relay inside the Right frame, in front of battery box, with a Zip Tie.

hth
:smiley_th
 

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Discussion Starter #13
I think I understand..so basically, the relay will allow the volt meter to only read from the battery as long as the ignition is switched on?
 

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..have a vulcan good day!
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I think I understand..so basically, the relay will allow the volt meter to only read from the battery as long as the ignition is switched on?
Yes, that is correct.
You will need to purchase a Meter, and a Relay, hopefully already have 24-30" of wire, a few (6 ?) terminal lugs, a crimper/wire stripper and a Zip Tie .
I have a LED Digital Meter sticky taped to my Handle Bar Clamp.

:smiley_th
 

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Discussion Starter #15
Alright so the quick and dirty hacked together volt meter worked. I rode about 5 miles, everything was fine the first mile or so, and then suddenly my voltage went nuts, jumping around between 10 and 18-19 volts. I almost thought I had a loose connection, but then it leveled out....at 18.7-19.2 volts when riding.

When I stopped at a light and kicked it into neutral, it went down to 13.1 to 14.3 volts. This fluctuated, but never went above 14.3 when idling in neutral.

As soon as I'd take off and hit 3rd gear, 18-19 volts. Anything over 18.5 volts and I'd get the crazy RPM gauge when revving the engine. At 18-18.4v, the bike rides ok, but sounds "off".

Gonna try it again tonight and see if the voltage spikes correspond to when my lights brighten. I'm assuming they do.

Does this mean I have a bad R/R? I'm also going to assume here; I probably need a new one.
 

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Discussion Starter #16
ImageUploadedByMotorcycle1407780049.289687.jpg

Photo of the aforementioned hacked together quick and dirty volt meter job. :)
 

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..have a vulcan good day!
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Alright so the quick and dirty hacked together volt meter worked. I rode about 5 miles, everything was fine the first mile or so, and then suddenly my voltage went nuts, jumping around between 10 and 18-19 volts. I almost thought I had a loose connection, but then it leveled out....at 18.7-19.2 volts when riding.

When I stopped at a light and kicked it into neutral, it went down to 13.1 to 14.3 volts. This fluctuated, but never went above 14.3 when idling in neutral.

As soon as I'd take off and hit 3rd gear, 18-19 volts. Anything over 18.5 volts and I'd get the crazy RPM gauge when revving the engine. At 18-18.4v, the bike rides ok, but sounds "off".

Gonna try it again tonight and see if the voltage spikes correspond to when my lights brighten. I'm assuming they do.

Does this mean I have a bad R/R? I'm also going to assume here; I probably need a new one.
without re-reading the whole thread....check out ALL your electrical connections....Remove & Clean ALL grounds....check connector at R/R....Clean Contacts ! 18-19 volts can/will fry your electronics / battery !
... have you checked the Stator AC voltage output ?

:smiley_th

EDIT: Did I mention Remove and CLEAN ALL Grounds ? LOL
 

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I would set your multi meter to ohms and tap the red lead into one of your stator leads and leave the black one grounded to the battery... Reading should be OL or 1 depending on your meter... If you get any thing other than those two r readings while riding, then you have a bad stator.
 

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Discussion Starter #19
...ok, so that didn't go so well. I pulled off the fuel tank and started checking all the electrical connections. Wherever I had previously fixed or replaced a wire I inspected, as well as looking at all the existing wiring. As far as I could tell, I didn't have any ground faults or shorts anywhere. I did notice my choke cable is broken, barely holding together by a few strands (outside is completely separated).

So that left the stator wires. I re-mounted the fuel tank, put everything back together except the side panel and got ready to test the A/C voltage coming off the stator wires. I have all three wires exposed, but zip tied apart so they don't touch anything. This allows me to easily clip the leads from my multimeter onto each one to test.

I went to start the bike and..nothing. Turned over and over, and over... and over.. nothing! Finally, I noticed in my haste I neglected to re-attach my front right spark plug cable. Whoops! Re-attached and tried again. Nothing. Gave it a few minutes thinking it was flooded and tried again, nope.

Finally I pulled the plugs one by one and tested for spark. All four plugs are sparking just fine, and the plugs smelled like gas when I pulled them. At this point I'm assuming the battery is low from all that cranking. I hooked jumper cables up to my car and tried starting again...

..this time it started right up! And shot straight up to 5,000 RPM with full choke applied. I lowered the choke (by pushing it in on the carbs, broken cable now) and checked the idler screw... and the lowest it will go is 4,000 RPM. I checked the throttle cable, but that seems fine. If I rev the engine it responds as I'd expect, just at 4,000 RPM and up.

I have no idea what I could have messed with aside from choke/throttle/idle screw that can affect the base RPM. Got frustrated and called it a day for now.

Help!
 

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Discussion Starter #20
Alright, fresh look at things today. Throttle was sticking, causing the issue. :rockon:

Finally tested the stator, at idle RPM and at 3500-4000 RPM I get the same reading between all three poles.. 11 to 11.5v

I knew it was going bad, when I first tested it back in April/May I was getting about 30-35v.. is it typical for it to go that bad that fast? Also, would this cause my voltage spikes?

Thanks!
 
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