Stator rewiring

[lalalandrus]

Need to learn to read.

[speedy231278]

Yup, another old age resurrection, but....

I have a spare stator, which I intend to attach nice new wires and a connector to, and run the feed straight up the left (as you sit on it) side of the bike to avoid all the nonsense of the current route that takes in almost a complete lap of the fuel tank. As an interim job, I intended doing this to the current stator, but only by trimming the existing wire back and soldering new ones one when I got back to decent material. However, in the end for the time being I simply replaced all the spade terminals as they were manky, and put a new connector on.

The reason I didn't go further was because I got some new wire based on the size of the original attached to the spare stator. It was sold to me as definitely being off an NC35, but then so was the clutch I got from the same seller, and it was stacked up as per an NC30, so I'm going to say that the parentage of it is dubious. Notwithstanding, the wire I got matched the external diameter of the original wire as fitted to the spare stator, this being 2mm. On the bike, however, the wire on the loom side of the connector is quite a bit heavier. Not as heavy as that of the output wires of the reg/rec, but it's probably half a mil bigger, which put me off using it on a long run. I'm sure I noticed in the past that there was a difference on both sides of the connector, although I couldn't say for sure without doing a side by side comparison if there's any difference in size between the original Honda wiring on the attached and spare stators.

Why would Honda use heavier wire in the main loom than is attached to the stator itself? Surely any benefit to heavier section wire will be lost due to the lighter stuff already having caused a loss up until that point, or is there some thinking that in combination there's less loss than if they ran the smaller wire all the way?

I still intend to have a plug for the alternator when I rewire it, as I figure that at some point I may well want to detach it from the reg/rec connector, and it would be easiest to do this via a plug like the standard arrangement rather than have to try and get the pinsout of the reg/rec plug.

If I use wire of the heavier grade found in the loom, it will require the holes in the rubber seal on the stock alternator wiring to be enlarged slightly to cope. I have no issue with doing this, but I wonder if there would really be any issues with running the smaller wire to the reg/rec? Yes, in theory there's more resistance per unit length, but there'll also be less of a run if I reroute the wiring. The stuff I have is rated at 16.5A, 198W for 12V, 396W for 24V and max 60V. To me, that sounds ample, however it's also only 1mm square, 2mm diameter. While it's the same physical size as the Honda stuff on the stator, I'm slightly nervous about the effect of using it for the whole run.

[Neosophist]

Yup, another old age resurrection, but....

I have a spare stator, which I intend to attach nice new wires and a connector to, and run the feed straight up the left (as you sit on it) side of the bike to avoid all the nonsense of the current route that takes in almost a complete lap of the fuel tank. As an interim job, I intended doing this to the current stator, but only by trimming the existing wire back and soldering new ones one when I got back to decent material. However, in the end for the time being I simply replaced all the spade terminals as they were manky, and put a new connector on.

The reason I didn't go further was because I got some new wire based on the size of the original attached to the spare stator. It was sold to me as definitely being off an NC35, but then so was the clutch I got from the same seller, and it was stacked up as per an NC30, so I'm going to say that the parentage of it is dubious. Notwithstanding, the wire I got matched the external diameter of the original wire as fitted to the spare stator, this being 2mm. On the bike, however, the wire on the loom side of the connector is quite a bit heavier. Not as heavy as that of the output wires of the reg/rec, but it's probably half a mil bigger, which put me off using it on a long run. I'm sure I noticed in the past that there was a difference on both sides of the connector, although I couldn't say for sure without doing a side by side comparison if there's any difference in size between the original Honda wiring on the attached and spare stators.

Why would Honda use heavier wire in the main loom than is attached to the stator itself? Surely any benefit to heavier section wire will be lost due to the lighter stuff already having caused a loss up until that point, or is there some thinking that in combination there's less loss than if they ran the smaller wire all the way?

I still intend to have a plug for the alternator when I rewire it, as I figure that at some point I may well want to detach it from the reg/rec connector, and it would be easiest to do this via a plug like the standard arrangement rather than have to try and get the pinsout of the reg/rec plug.

If I use wire of the heavier grade found in the loom, it will require the holes in the rubber seal on the stock alternator wiring to be enlarged slightly to cope. I have no issue with doing this, but I wonder if there would really be any issues with running the smaller wire to the reg/rec? Yes, in theory there's more resistance per unit length, but there'll also be less of a run if I reroute the wiring. The stuff I have is rated at 16.5A, 198W for 12V, 396W for 24V and max 60V. To me, that sounds ample, however it's also only 1mm square, 2mm diameter. While it's the same physical size as the Honda stuff on the stator, I'm slightly nervous about the effect of using it for the whole run.

You think too much

It depends on the resistance of the wire, but it should be fine.

Back to the original question.

Stator is 350 watts maxium draw, lets assume the reg/rec and everything is ideal at 14.4 volts.

(bear with me I had a few beers and can't think that striaght but..)

350 watts @ 14.4 volts is 24 amps.

However, this is a 3 phase stator so divide the total amps by the 3 wires, that is 8 amps maximum load per wire.

(8 amp / 14.4v = circa 115w per phase)

Things like the headlights are 120 watts on full beam for the pair, which is more than the single phase of one of altenator wires as its DC volts there.

I think that should make sense?

[pip]

What is the stator output voltage? Neo, you state it as being 14.4v - are you sure that that's the output volts from the stator?

Running the stator - RR wires is a more direct route is a good idea, fitting larger wires can't do any harm either.
Personally I remove the stator - loom connector & solder/heatshrink the wires if this connector is anything less than perfect.

My gut feeling is that most charging/RR issues are down to poor connectors.

Pip

[speedy231278]

You think too much

It depends on the resistance of the wire, but it should be fine.

Back to the original question.

Stator is 350 watts maxium draw, lets assume the reg/rec and everything is ideal at 14.4 volts.

(bear with me I had a few beers and can't think that striaght but..)

350 watts @ 14.4 volts is 24 amps.

However, this is a 3 phase stator so divide the total amps by the 3 wires, that is 8 amps maximum load per wire.

(8 amp / 14.4v = circa 115w per phase)

Things like the headlights are 120 watts on full beam for the pair, which is more than the single phase of one of altenator wires as its DC volts there.

I think that should make sense?

Yes, that all makes sense. What I didn't know was the max rated output of the alternator, so I wasn't sure what the max load on each phase might have been. However, after the direct reg/rec battery mod that I did, I was getting mid 14v at 5K, so now I'm happy that nothing will melt unless somehow something goes amazingly wrong and the stator suddenly manages to output a current far higher. By your sums which I agree with, the wire I've got is pretty much rated double the capacity of the stator, which leaves plenty of room for error.

I was just confused about Honda putting heftier wire in the loom and wondering why, seeing as smaller stuff would presumably be cheaper, and you'd only go heavier where the load demanded it. I don't see why they didn't just use the weedier stuff all the way. It's not like the loom will be used on other bikes, after all!

[speedy231278]

What is the stator output voltage? Neo, you state it as being 14.4v - are you sure that that's the output volts from the stator?

Running the stator - RR wires is a more direct route is a good idea, fitting larger wires can't do any harm either.
Personally I remove the stator - loom connector & solder/heatshrink the wires if this connector is anything less than perfect.

My gut feeling is that most charging/RR issues are down to poor connectors.

Pip

With no load, it puts out around 12-13V per phase at idle, and somewhere around 50-60 at 5K rpm. However, in previous discussion I've been told it only does this due to not having load, and will not rise above 15 or so under load. I was also told that if you measure the AC output under load there'd be no meaningful reading given by a normal meter. I have no idea why this would be the case, but then I'm not an electrician. I understand the basics of Ohm's law, and why minging wire and connectors cause so many problems due to corrosion effectively reducing the cross section of the wire and increasing resistance and therefore causing voltage loss and damaging the connectors further through heat buildup (which is why I have new connectors on the reg/rec and alternator, the former was destroyed, and the latter was melted together in places).

I was going to simply solder the stator to the loom, but then I though Sod's Law dictated I'd have cause to unplug it at some point and be forced to cut it out and resolder. Even when I got direct, it'll have a plug, however it and every plug on the loom from now on will be treated to some of that electrical type corrosion inhibiting treatment and a wrap of tape to stop crap getting in in the first place!

[JC120]

I did when I fitted the GSXR statot

Chop them off, splice adn solder then heatshrink them. all good. Got me some connectors from an autoelectrics shop online

That's what I did as well. All good