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Discussion Starter #1 (Edited)
This may not come to suprise to many but after my battery almost went dead a couple of week ago I went a check the voltage reading from the stator and the R/R, apparently everything was fine but after a while running (15-20 min) the voltage readings started to drop significantly and the cables running from the R/R to the juntion box was extremely hot... the white cable from the R/R (the positive lead) was no longer white but brownish black from the heat...
Well, after a bit a changed the connector and put some new cable to the white cable coming out of the juntion box... and magic... right now I'm getting 15 volts at a mere 1500 rpm's and a constant 14.5 above 3500 rpm's... just as the kawasaki manual says it should... no more parasitic looses over the wiring...
Given my bike is 13 years old I'm guessing that the deparment of cheapness in Kawasaki had a hand in the wiring desing and selection (anyone remembers the grease in the splines???:doh: ) so they make it a pretty tight fit (electrical speaking) for the power demans of the bike but the you have to add the bends (some derating needed) and the bundleing of the wires (some more derating) and the the temperature (even more derating) and you end up with wires that after a while are no able to carry the current of a brand new wiring harness. For some more reference go to: http://www.interfacebus.com/Component_Derating_Guide_line.html

This is not really and issue in most parts of the wiring harness because they conduct a rather small amount of current through them but the small batch of cables come from the R/R, first they are subjected to some elevated temperatures (thanks to the goat belly) and then they have some major current going in and out of the R/R (about 12-15 amps at full electrical load) so what appears to be 16 AWG wire (rated for 22 amps at room temp) is not sufficent to carry all the current generating heat, resistance and voltage drop... now for the interesting part, since the electrical power requirments of the bike really does not change that much wether be runnig at low rpm's or screaming on top rpm's, the voltage the system is runnig becomes crucial as a lower voltage needs more amps to sustain a constant power draw from the bike... the more amps that come out of the R/R equals more heat... and in the end more heat means an ugly dead to the diodes inside the R/R...:BLAM:
Apparenly the fix worked as no heat is really detectable in the new wire but still the 3 leads from the stator are getting some what hot so they are getting changed too...
If you are not seeing 14.5 to 15 volts at the battery post and even better at the accesory leads behind the headlight I advise you start tracking where the voltage drop is coming as is very likely that it's coming form the R/R wiring... do yourself a favor and save your R/R from frying...
 

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What gauge wire did you use for the rewire?
 

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Discussion Starter #3
I used 14 gauge wire... I had it at hand for the job... seems to have much thicker insulation than the original wire.... but I'm going to use 16 gauge wire for the stator wires... they do seem a bit smaller that other wires...
 

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I may give it a try. My white wire has charred the connector going into the R/R. If it's getting that hot, the other wires can't be too far behind.
 

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I've also heard that the connectors oxidize from the heat, which in turn causes even more heat.
 

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on my frankenstator mod i used 10 gauge teflon wires to lead off the stator. they are good up to 200C which is like almost 450 F. i think we have other problems if that is reached. I plan at sometime to rewire the entire bike in a few years when i tear her down to 'custom' her. While in there i will prolly update and improve everything, like for instance the ignition control running throught the kill switch and everything through the ignition. I know they had relays back then, and they dont use but a fraction of an amp at 12V so i dunno lol.
 

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I believe I used 12 ga wire to go to my coils when I modded. I'm no engineer so pardon this potentially stupid question, but can the wire be too large? I mean, is there a point where you've gone too far, other than the obvious 6 gauge wire being too big to bend or attach to any spade connector!
 

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Too large - No.
 

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If you can find it, wire rated at 105 C is a good choice for wires that have to run near heat sources. I used some when I took out the bullet connectors on the yellow wires. Good stuff.
 

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fergy said:
I believe I used 12 ga wire to go to my coils when I modded. I'm no engineer so pardon this potentially stupid question, but can the wire be too large? I mean, is there a point where you've gone too far, other than the obvious 6 gauge wire being too big to bend or attach to any spade connector!
Nope.... the thicker the wire, the less resistance it has. less resistance=very good. now if you really wanted to save some space you can try going from stranded to solid core. Aside from being stiffer, its resistance is typically the same as stranded of 2 gagues larger. I.E. resistance of 12gauge stranded= 14 gauge solid. this is why houses are done in solid core. But only use it in places with lil movement. like the chassis wireing, dont use it to wire up your switches...instead wire up along the chassis with it, then splice over to a stranded the rest of the way...

also resistance burns watts. i figure in this bike there is prolly 15-20 watts being burned in bad wireing....
 

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Discussion Starter #13
RepairmanSki said:
So you ran new wire from the J-box all the way to the ignition switch?
Nop... that wire is the one connecting the R/R to the juction box... there is no connection from the R/R to the ignition switch... sorry if it was confusing...
 

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I think I'll check this stuff out this fall.....
 
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