Wiring harness / charging and esr350 build


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So I looked through drewpys post about rewiring and planning on doing mine, however I needed more information and hit up a local electronics repair shop in addition to electrosport about their esr350.
So I made a harness, but it wasn’t as clean as I liked and everything was soldered, which sucked when I rebuilt the bike as I had to cut a lot of stuff. So Im redoing it to look professional since the rebuild looks really nice.

I still have yet to check the ohms on my field coil, but if I remember correctly they tested within spec ~4 ohms. The stator I took last fall to a local shop that rewinds alternators and such and they tested it and everything looked great and tested great. However the wires are super stiff after the grommet, so I will be rewiring those from the stator and the field coil for fresh wires and I know they will be good to go for a long time to come.

I had the esr350 before purchased through 3rd party vendor for less than electrosport actually has them for, and I highly suggest buying through the actual company so they can take care of you. He also said to be careful with some 3rd party sellers as they may be similar parts or look the same but with a lower build quality because I asked the tech support guy about them, amazon sells for a little cheaper and you can get an additional warranty through amazon, but at least I know electrosport will stand behind their product, assures me high quality, and hassle free warranty.
He said typical resistance you want for the regulator portion is 5 to 6 ohms, but if our bikes are supposed to have 4 it will still work as long as it’s healthy. As systems age and lose resistance he said it will put more anperage through the regulator causing it to overheat and that’s where they see their failures are coming from. Our system designed with 4 ohms he said won’t be a problem for the regulator.
2 wires for regulator portion.
Brown connect to +12 v source (sense wire)
Green connect to field coil green.
Then the black field coil wire connects to ground.

The guy at my local electronics repair shop told me even though the r 292 works, it could potentially be running at the high end of its capacity and burning up and or malfunctioning since it failed prematurely. He also recommended I rewire the wires from the field coil and stator and not use heat shrink. Said there’s mesh tubing rates for 1,000 degrees that’s better suited and it won’t get hard and brittle like the heat shrink does over time. And between the tubing and the insulation on the wires it is sufficient to handle the area where the chain is.

I also am running all LED lights (headlight, tail light, license plate light, underglow) so 16awg is a bit overkill he said but will work well. Stator and other wires like for ignition I have 14 gauge wire for. No blinkers needed, at least in my state I can just use hand signals.

I made a rough layout wiring schematic I will be using as my guide and will attach it.
With any luck, I will probably not really ever have to go digging into the wiring again.

oh, and I got waterproof connectors from the electronics store for all the connections except the stator, field coil wiring which will all be soldered and heat shrink with the glue they have inside them.
Will try and post pictures as I go.


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