stator connectors toasted - SH775 to the rescue

[superawesome]

Hi all,

recently discovered that my stator connections have melted - again.


History is, until few years ago I had the stock r/r combination on my 1978 GS1000, so when that failed I replaced it with a Shindengen SH232 shunt regulator off ebay. Stator paper checks were all well at the time, and still are. All diodes working and resistance is ok, I got 14.2v at 5000rpm. Voltage drop a bit higher than 0.25v (~0.3v) but I guess that's within limits. So it seems stator and r/r are still good.

Also, only 2 of the 3 connections are melted, the 3rd looks as new. Since I only used crappy spade connectors (the ones with the hard plastic casing) I would assume that, due to bad crimping, one of the the three got loose and the other two carried the extra load. Would that cause connectors to melt?
Another idea would be that the sense wire on the SH232 delivers wrong results. I have that connected to the brake light switch at the back. Gotta test that next.

As a temp fix I replaced the connections (took the plastic off the spade terminals, soldered them and shrinktubed everything), but i didn't go out for a test ride yet. As a longterm fix I ordered some decent spade connectors, and got me a used SH775 off ebay (looks legit, coming from these guys), but shipping from US takes a few weeks, so it's hopefully here for christmas.

[Gorminrider]

Bad crimps are very common. Your assumption is correct but it's usually obvious with a magnifying glass. Good Crimps can handle everything your stator can pump out so "sense wire" is a distraction. If your Voltage is ok across the battery, it's in a good spot.

The 1st easiest fail is in stripping that nicks strands. You use strippers to nick the insulation - they never touch the copper....Cheapo connectors can be made to work but even they need a decent crimping tool or a whole lot of tries with the super- cheapo stripper-crimper combo you find in dollar stores.

Solder is ok where there's no hope for crimp connectors but it's another learning episode involving too much heat, melting insulation and copper-hardening. And solder is awfully rare in car and motorcycle factories except on electronic boards.

[Nessism]

Bypass the factory wiring and install your SH775 like this...

SH775 Install by nessism, on Flickr

[Rijko]

Switzerland ... do you have a light switch ?

If so and you hardly use lights the 3rd leg
Is practically unused.

[superawesome]

Rijk, I did remove the headlight loop few years ago.
I think I go with "bad crimps" as a suspicion. Should be better now after being redone, but I have been lurking at a SH775 for years anyway, so I'll wait for that one as a final fix.

Thanks guys

[superawesome]

SH775 arrived earlier than expected, Florida to Switzerland in 2 weeks. Nice.
Here it is (superficially cleaned).


Bought from suncoastcyclesports. SH775 + harness + shipping = 100USD.
Had some decent crimp connectors (spades and bullets) ordered that arrived in the meantime as well.
The SH232 I had before just fitted tightly in the original spot, but this one was too big, would have needed an extra bracket. So I placed the SH775 next to the battery box, lots of space there (not so much behind the left panel).
I got a charging voltage of ~13.8v above 2000 rpm. I know I have some resistance in the circuit, but that's another topic.



Device still needs to be rotated 180° so i can clean up the wiring (atm airbox pushes the wires down).

Just out of interest, what would happen if 1 of the 3 stator connector got loose? I assume the SH775 would just regulate the power and I'd end up with an empty battery at some stage right (instead of fried connectors)?

[Brendan W]

This is what happens when crimped bullet connectors get loose inside the generator cover. If you disconnect a phase at the R/R you will be down on charging current but you might be surprised to find that it still works on two phases only.

https://www.thegsresources.com/_forum/showthread.php?233509-Please-confirm-I-need-a-new-R-R-and-stator&highlight=