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Discussion Starter #1 (Edited)
Hey guys, Im not sure if I need to be concerned or not? As most of you know I just replaced my whole charging system. The other night when I completed my rebuild and started the bike it was producing voltage up to 14.55volts at 3000rpm and running the best its ever ran in my ownership, now this morning I get up to head to work on it and I noticed it was popping again on the warm up, left side to be exact! so on ride to and from work it ran great but I thought when I get home Im going to check it again and see what its producing. Low and behold its NOT! At 3000 rpm its only putting out 12.65 volts! Instead of the 14.plus that it should be. So needles to say panic just bout set in, so I cut the three stator wires from the R/R as I had solderd them and tested the stator for continuity on all three legs and all passed, started the bike ran it up to 5000 rpm and checked for a/c voltage and got 44.6, 45.1, 46.3, so that tells me its producing but I really thought it should have been higher?? I cant find the propper way to test my R/R to rule it out, I did find one video saying to disconect the negative battery lead and test for a drain of the battery with every thing off and I performed it and with the multimeter it shows I have a drain somewhere, could it be the R/R?? The video says it very well be. Im at a loss here and not sure what to do or where to start again,Ive put less than 200 miles on it since the rebuild and I do know I cant sink another 3-400 back into it again right away.
 

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Discussion Starter #2
Ok, Those stator numbers I showed earler was a test from a groud to a leg of the stator and those were the numbers I got, I just retested all three legs to each other in all three orders and got high 60's and low 70's on the volt test.Still with no continuity.
 

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..have a vulcan good day!
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Ok, Those stator numbers I showed earler was a test from a groud to a leg of the stator and those were the numbers I got, I just retested all three legs to each other in all three orders and got high 60's and low 70's on the volt test.Still with no continuity.
Stator seems good.....check your R/R wire harness (pinched?)....especially the R/R connector connections.
Ensure the R/R's ground is good.
hth

:smiley_th

btw: The case of the R/R IS NOT ground ! Think of it as a complete plastic casing.
 

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Linkmeister Supreme
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Scott, my 1991 model has never generated anywhere near 14 VDC. The last time I tested it was 2 or 3 years ago and the highest voltage I got between 2-5k rpm was between 12.5-13.0 VDC or so. IIRC the highest voltage occurred at 3k rpm and dropped by 0.1-0.2 VDC as rpms rose to 4k-5k rpm. :confused: Not sure how to explain that anomaly.
BTW it runs perfectly from that time until today..

I have never checked the three yellow stator lines for AC voltage, so can't help you there. I seem to remember someone 3 or 4 years ago reporting AC voltages as high as the low 70s, but do not recall if that was considered excessive or normal.

Having the DC voltage start at 13.2 at 2k rpm and rise steadily to the mid 14s at 4-5k rpms is a perfect world occurrence.
Not sure how often it happens in reality.

If I have time tomorrow, I will check charging voltages again to confirm what the scoot is doing now. :)

EDIT: Just found paper bookmark in Clymer manual with results of voltage test done Sept 18, (no year marked down).

Engine OFF 12 v
Engine started on full choke, 1500rpm- 12.5-13v
Idle, choke off--rpm unknown--12.85 v
2k rpm--13v
3k rpm--12.78 v
4k rpm--12.75 v
5k rpm--12.75
6krpm -- not recorded

Results are close to what I remembered.
 

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FREEBIRDS MC CENTRAL NY
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hell Melissa Fahye is at 11.2 at idle right now and 12.5 @3500.tried a rectifier from the 600 ninja i just bouvht and still the same.looks like i git some work to do.​
 

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Sparky!!!
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Scott, my 1991 model has never generated anywhere near 14 VDC. The last time I tested it was 2 or 3 years ago and the highest voltage I got between 2-5k rpm was between 12.5-13.0 VDC or so. IIRC the highest voltage occurred at 3k rpm and dropped by 0.1-0.2 VDC as rpms rose to 4k-5k rpm. :confused: Not sure how to explain that anomaly.
BTW it runs perfectly from that time until today..

I have never checked the three yellow stator lines for AC voltage, so can't help you there. I seem to remember someone 3 or 4 years ago reporting AC voltages as high as the low 70s, but do not recall if that was considered excessive or normal.

Having the DC voltage start at 13.2 at 2k rpm and rise steadily to the mid 14s at 4-5k rpms is a perfect world occurrence.
Not sure how often it happens in reality.

If I have time tomorrow, I will check charging voltages again to confirm what the scoot is doing now. :)

EDIT: Just found paper bookmark in Clymer manual with results of voltage test done Sept 18, (no year marked down).

Engine OFF 12 v
Engine started on full choke, 1500rpm- 12.5-13v
Idle, choke off--rpm unknown--12.85 v
2k rpm--13v
3k rpm--12.78 v
4k rpm--12.75 v
5k rpm--12.75
6krpm -- not recorded

Results are close to what I remembered.
Gordon, Scott here did the MOFSET upgrade when he redid his charging system, so he should be hitting 14.5Volts at ALL engine speeds. Scott, send me a pm with pictures of how your R/R is installed please
 

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Linkmeister Supreme
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Thanks for the info slim. I missed that in my frequent long absences from the board these past few months. From what I remember about the MOSFET r/r upgrade you are right, he should be getting over 14 vdc at all engine speeds.:smiley_th
 

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Discussion Starter #8
Slim I will send you some pics after I get off off work later this afternoon. Thank you guys for the info.
 

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Not sure if you have done it yet, but check for a short between the yellow wires and the engine case.
 

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Discussion Starter #12
ok, so here is what I done, is it the right way? No most likely not but I had to try something as I had no more money to spend on it at the time, I also orderd what was recomended by others but weather it was me not understanding or bad recomendations Im not sure and at this point I really dont care.
This is the wiring kit I bought, thinking it was the right one for the R/R that I bought off of ebay. With that said from the looks of the pic they dont match.




My solution since I didnt have the right connectors Was to cut off the kit ends cremp and solder ends to the wires and attach them that way, and fill in all the voids with silicone which I done as you can see in the pics.




With lotts of time to think about what I had done today and any way to make another attemp before I throw in the towel on thir R/R as I really dont have any more money to put into this thing at this time I decided today that I would remove all the plugs and clean up all of the silicone off of the R/R inwhich I done, then I decided what the hell! I feel like I dont have nothing to loose at this point so I solderd everything back in place, yes I solderd all conections directly to the R/R and guess what? It worked! Bingo I hit 14.5 volts again! So! I decided to take the bike out and run it, I ran it kinda hard for about 5 miles, got it good and hot. Got back home and retested it and I be damed if its only puting out 13.6 now. I lost nearly a full volt in 15 min of riding and less than 6 miles. Is that a sign my R/R is bad? I know my ways of having it hooked up is very questinable but there is no way it can be a short, not possible! its solderd at all points.



It kinda looks like I have the yellow wire hooked into a blue wire but thats not the case its just blue heatshrink tubing, it is the yellow wire underneth.
 

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Sparky!!!
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Go test your battery voltage, then go for a ride, recheck charging voltage, them shirt the engine of and retest battery voltage... I think you are OK man. As long as the battery is getting over 12.5 volts you should be in the clear.... One more question... Are you using an AGM MF battery?
 

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Discussion Starter #14 (Edited)
Yes slim I am using a AGM battery. This is the battery I'm using, paid 105.00 for it.


I tested it again this morning before start up and got 12.99 v on the battery, started it and got 14.5 at 3G, rode it to work which is 34 miles one way, tested it once I got to work and it was reading 12.7 at around 2G, I couldn't run it up much didn't want to wake my boss up they live on site. This was at 2am.
 

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Discussion Starter #16
Slim I didn't think to check it, I will recheck all of it again after I get home from work. I will say that the exasht wasn't popping this morning like it has been, I'm thinking it wasn't getting a good solid contact on the R/R tabs before. It's running great, it feels like it has way more pep now. Maby this is just the way it's going to operate? Could the R/R have a bad diode or something that would malfunction once hot? But operate normal while cold?
 

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..have a vulcan good day!
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Slim I didn't think to check it, I will recheck all of it again after I get home from work. I will say that the exasht wasn't popping this morning like it has been, I'm thinking it wasn't getting a good solid contact on the R/R tabs before. It's running great, it feels like it has way more pep now. Maby this is just the way it's going to operate? Could the R/R have a bad diode or something that would malfunction once hot? But operate normal while cold?
New R/R.....That is possible, but odds are unlikely....

Have you performed the Spark Plug Coil Mod ? ...it places 100% battery Voltage - 100% anytime the Ignition Switch is on ....to the Spark Plug Coils.
Made a big difference in my bike performance....including starting !

:smiley_th
 

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Discussion Starter #18
No I haven't, that might be something to look into once I think I have this issue solved. Where would I find info on it at? Is it in the sticky?
 

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..have a vulcan good day!
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No I haven't, that might be something to look into once I think I have this issue solved. Where would I find info on it at? Is it in the sticky?
Below is Copy & Pasted from a .doc

-Sorry, Simple Wiring diagram did not paste......
This Mod will replace existing +12V coil wires, ensure to tape off old front coil 12V wire (use the rear coil +12V wire to trigger new relay).
This should be a 30 - 45 minute job, start to finish.
I utilized the rear Ignition Coil red wire (ignition switched) to trigger Relay, Pin #86
mounted relay fwd of battery box on the (upper) right frame rail with a Zip Tie. I utilized 14 gauge wire to all connections on relay and to each Ignition Coil.
The relay 12v Battery input (ring connector) I attached to the hot (battery side) of the Starter Relay. I did not utilize a fuse/holder.
Ensure to thoroughly clean Coil connections...and fwiw, .....Ignition Coil polarity does not matter.
hth
:smiley_th

Coil Wiring and Relay mod (this is not that difficult)
________________________________________
Direct wiring the coils to the battery using a relay to bypass the original wiring harness and thus providing full battery voltage level to the coils.
This mod would be used generally for older bikes that have questionable wiring. A quick way to know if this will help your situation, is to measure voltage at the battery with ignition on, bike not running. Should be around 12.5 volts. Then measure voltage on the red coil power wire, again with ignition on and bike not running. If you have less than 12 volts or less here, you are losing voltage somewhere in your wiring, through the numerous switches and connectors before getting to the coils. I did this now on my 2002 just to test it and see if it would help the hot starting problem. So far it, combined with moving my regulator/rectifier, seems to have made all the difference in the world. Time will tell.

Parts needed:

Basic 5 pin automotive relay. Can be found in the bling section of your auto parts store.
Inline fuse holder. I prefer the waterproof mini fuse holder for this.
10 A mini fuse
12-14 gauge wire, red and black
Various insulated spade connectors (6) and a ring connector, crimp type for 12-14 gauge wire
Soldering iron and solder - Heat Shrink Tubing


Figure 1. (above) This did not paste

I borrowed this diagram from folks at KZrider.com, where I am also a member. Note: Our VN750's have RED wires connecting the coils to power, not Red/Yellow as in the diagram. Another note, my relay had #30 instead of #36 on the Power connector.
Remove the front left side panel that is located above the left air filter. There are two phillips screws holding this panel on. It's the panel with the reflector on it, in front of the fuel tank. This side panel is covering the front coil.



A. Automotive relay (Approx 1" Square with # 36, 85, 86, 87 labeled pins) Mini schematic incl.
B. Original rear coil power wire, going to relay as the relay trigger.(Red Wire)
C. New 12-14 gauge red power wire going to both front & rear coils.
D. Inline fuse holder.(10 A)
E. Ground wire (to frame)

Fish a red 12-14 gauge wire up from the battery box area, under fuel tank, to the front coil. Leave yourself extra wire at the battery box end, enough to be able to attach this end to your relay. I put my relay in the right front corner of the battery box area, electrical tape around contacts, then taped/zip tied mounted to my frame. You might have to loosen the fuel tank and raise it slightly to fish this wire through. Make sure it stays under the frame where it won't have the tank sitting/rubbing on it. Strip the wire and tin the tip with solder. Crimp on an insulated female spade connector. I used insulated spade connectors that have a cover over the entire connector. Pull the red wire off the coil, put some dielectric grease on the new connector and connect the new wire onto the coil. Wrap the old connector in black electrical tape and push it under the frame. I didn't cut any existing wires to do this mod. It can be reversed easily if needed.
Reinstall the side cover over the coil.
Measure from the power terminal of the rear coil to a location where it can intersect with the other end of new front coil wire you just installed and cut another piece of red wire. Mine was about 8" long. Strip both ends of the 8" wire. Taking the wire you attached to the front coil, find an area of this wire where the 8" wire can intersect with it, and cut the long wire, and strip the end. Now using the rest of the wire you just cut, strip it's end and join all three ends, (end from wire from front coil, end of 8" wire, and other end of wire you are going to use to go to the relay) and twist them together. Tin the twisted wire with plenty of solder, then shrink wrap/ tape the connection. Tin the other end of the 8" wire and crimp another insulated female spade connector to the end. Remove the existing red power wire from the rear coil, dab a little dielectric grease on the new connector and connect the spade connector from the 8" wire to the power terminal of the rear coil.
The remaining end of wire coming from that 3 way junction you soldered needs to be stripped and tinned, and a female spade connector crimped on, DE greased and connected to the terminal on the relay labeled 87. This is your power to the coils from the relay.

Pull the tape back on the original red wire (from the rear coil) to give you enough slack to be able to reach the relay with the wire. Again, dab a little DE grease in the connector and connect this original red coil power wire to the post on the relay labeled 86. This original wire will now be used as the trigger to activate the relay when the key is turned on.

Tin the leads on both ends of the inline fuse holder (D Figure 2) and on one end crimp a ring connector that is large enough to fit the battery terminal screw through it. On the other end, crimp another female spade connector, dab some DE grease and connect the spade connector to the terminal on the relay labeled 36 or 30,( depending on which relay you have. Insert your 10 amp fuse into the fuse holder and close the rubber top.




Take a piece of 12-14 gauge black wire and cut a piece long enough to reach the relay, and go to the grounding point on the right side of the frame, above the starter relay. Strip and tin the ends and on one end crimp another spade connector and dab DE grease into it and attach it to the terminal on the relay labeled 85. Remove the bolt holding the ground to the frame, clean the area with a wire brush (I used my dremmel with a wire brush tool--wear safety glasses as these little wires become missiles!) and attach your original ground wire and the new black ground wire going to the relay, and tighten well.

Now take the other end of your inline fuse wire with the ring connector and put it over the positive battery terminal and connect the battery terminal bolt and tighten securely.

Reattach your battery ground cable to your battery and tighten securely.

I wrapped black tape around the relay and the wiring connections and then taped/zip tied the relay to the right side frame in front of the battery.

Some side notes: While doing this mod, I noticed that the starter relay positive terminal was rusty so I pulled it apart and cleaned the connection well. There is also a two prong connector that plugs into the starter relay and I pulled it off and the terminals were corroded, so I cleaned them up as well, used DE grease on them and put them back together. Just things you should check while you are in there doing this stuff.

That's it. Now your power to the coils comes directly from your battery so weak wiring no longer comes into play, and maybe it will have a positive impact on the hot starting issue as well.
 

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Discussion Starter #20
Thank you william, that just might make for a rainy day project. Slim As I was about to leave work I tested my battery before start up and got 12.9V, at idle I got 13.3V at 3G I got 14.plus, rode home, tested it again at idle got 12.9V ant at 3G i got 13.0 engine off I got 12.7V
 
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