1981 xs400 special regulator

Does anyone know if the regulator on a 1981 special is adjustable or is it solid state. I'm getting 15 volts at the battery at 5000 rpm.


Thanks

Solid state. Only the 77-D and the 78 2-E had the mechanical ones.

The regulator reads battery voltage on a brown wire, at the reg/rec check the voltage on the brown wire, compare it to battery voltage. they should match.
If the voltage is low at the reg/rec the reg/rec will over charge by that much. Also check the grounds for the reg/rec. This can lead to a low voltage at the reg/rec.
Check every connection from the battery along the red wire to main fuse, from the switch on the brown wire to the reg/rec. Often the contacts inside the key switch are the problem. most switches can be taken apart and cleaned.
Leo

I did my best with the search function and found this thread.

I have a XS360D project and am currently in the process of sorting out the wiring. It has the stock mechanical relay regulator. ( working fine as is the rest of the charging system)

What is the purpose of what seems like a much earlier style mechanical regulator when other bikes of the same and earlier model years came with solid state? ( I have had some early RDs and 650's that had this same mechanical type and after some research today, I see the same unit's use was extended through 1980 on the 650's )

Was the field coil itself of a lower voltage requirement on the 71-80 650s and the early 360/400? Or is the requirement the same as other Yammy field coils that use the solid state unit?

I have had earlier RD's/ TX etc that came with solid state units. Is this just another example of parts bin use in design and manufacturing and both the solid state and mechanical serve identical field coil requirements ?

Just trying to get edumicagted In the photo below in the left is the stock mechanical regulator from my '77 D model 360 and on the right is a stock solid state unit from a '76 C model RD. Connector plug / and mounting aside, are they interchangeable? I would think so.

The 76-77 xs360 and the 77-82 sohc xs400 used the same style charging system/field coil alt. The solid state regulators for the xs400 where designed to keep the volts to a 14.7 max and the mechanical ones 14.5v so as long as the one you have does it should work.

thanks! I was just wondering why they would use such a giant mechanical relay when solid state units were available and installed on other Yamaha models. ( and the solid state is much thinner when thinking about future customs and locations to mount regulators)