1977 GS400 rectifier and regulator replacement

[Guest]

Hi all,
can anyone please tell me, can I replace both my rectifier and regulator with an r/r like the SH-775. I have read the stator papers (fantastic) and tested everything. My regulator tests good but my rectifier not so. Also my stator tests good except I get voltage between the stator wires and the neg of the battery, so on the way out I believe. I would like to replace the stator, rectifier and regulator ( seperate units on my bike)
Any help muchly appreciated.
Cheers

[Steve]

Yes, that is very possible.

Just be aware that there might be an extra wire coming from one of the stator connectors. I have seen some that had a "Y" where it plugged in to the rectifier, don't remember where it went, but it won't be needed with an SH775. You may have to extend a wire or three in the harness, but make sure that all three wires from the stator go directly to the R/R. In stock configuration, one wire will disappear into the harness and end up at the headlight switch. It then comes back down the harness and goes to the rectifier.

Since your bike has a functioning headlight switch, that wire actually makes sense for the stock charging system. When the headlight switch is OFF, a second set of contacts in the switch opens up one of the three windings on the stator, so it does not charge too much, overwhelming the regulator. When the safety weenies in the US DOT decided that we needed our headlights ON all the time, Suzuki first blocked the switch, and in later years, removed it altogether. When they removed the switch, they put a short foldback loop on the headlight side of a connector under the tank (some were in the headlight bucket). They did that because some world markets, like yours, still had a switch, and they could still use the same main harness, but add a different sub-harness to the handgrip.

Your SH775 will be able to handle the charging load just fine, whether your headlight is ON or OFF.

.

[Catcalledsprocket]

Hi Steve, thanks for your help. Good info, now I can go shopping with confidence!
Cheers mate.