It is looking like I am going to need a regulator here shortly. Should I be using a RR40 or a RR98 for my 1993? I don't recall seeing a seperate ground wire like the RR98 has, but that is just going from memory. I haven't messed with the RR directly on the bike yet.
If the RR98 is better (somebody had posted it is a bit heavier duty), I don't mind making small modifications. But I don't have anu spare yamaha plugs laying around.
In the U.S. it depends on which regulator came with yours. I also have a 1993 and it looks like there was a change during that year. Check and see if yours is basically a box which the wiring harness plugs in to, or does it have about a 16" pigtail on it that plugs into the main wiring harness. (neither one has a ground wire outside the plug). I made a short harness from my old pigtail and it works fine, without the pigtail the reg wouldn't reach to where it mounts outside the frame.
After some research I've decided to order and install this mosfet type regulator kit http://motoelectrixc...-rectifier-kit.

One of the advantages of this kit is it is a mosfet type of reg/rec, if it fails it is designed so there is no danger of it frying your battery, stator, and ecu. The kit is made by shindengen the same company that make most of the newer oem mosfet type reg on Jap bikes.
There are many companies making replacement (non-mosfet type) replacement regulators for the Tdm. Most are shunt type units (cheaper to make). These replacements when they fail can fail and not charge (if your lucky) or they can fail in a manner that allows the systems to go into full charge mode and possibly frying your battery, ecu, etc. One quick way to tell what type you are installing is marking on the replacement reg. If the reg has an SH printed on it (left on the pics below) it is the older shunt type of regulator . If it has an FH on it, it should be a newer type, which can eventually fail, but when it does there's no danger of it frying other components.
As an added note if you decide to order an oem style replacement don't trust the pictures on the sites. The one I originally ordered had a picture of a reg with the pigtail on like my original but arrived without one. A lot of sites use "stock" pictures, not pictures of the actual reg. Talk to them before ordering, I'd also ask them to tell you whether the unit has the tell tale "SH" or "FH" printed on the side, remember you want one the the "FH" on it. The one I got is the shunt type, it works of course and gets me back and forth to work, but the kit above is on it's way so I won't have to stress possible extra damage of the older "SH#t" type units.


Edited by marrk_us, 21 October 2014 - 12:51 am.