When I first unboxed my Doppler ER3 with clutch function, I noticed right away that
these things come with no manual/instructions. After searching around I couldn't find
anything on how to install this thing, so I decided to document my method and put it
in the Wiki for people to use in the future.
Remove your stock variator all the way to the case, just leave the "double D" spacer looking out (above left)
Next reinstall your stock clutch bell and adjusting washer.
Also reinstall your stock pressure plate spring washer (above left, I like to use two for xtra kick). Next push your
needle bearing races out of your stock variator and slide them into your new ER3 assembly. These are the only
parts from the stock variator you use. You not use the stock plastic "shaped" washers. Now is a good time to
make sure there is grease on the new bearings so slather a little on them with a stick.
Next install the stock starter clutch housing over the ER3 assembly and tighten the 1 1/4 nut. I wish I had more
pictures of this step, but some were lost. Place the variator down on a table and place the beveled washer in
the center of the nut with the beveled side facing up. (above right)
Install the centrifugal clutch thrust plate and thrust balls ( I like to use 3 staggered ) down inside the locking
ring so that the plate rests on the beveled washer. You can see that the thrust plate has a "Double D" or "keyed"
hole in it. A good assembly rule is to line all the "keyed" componets so that they sit in the same direction using
the pivot posts as a reference. If you get confused assembling the stock portion of the clutch, you can view
more pictures here: 
Slide variator assembly onto crank, you should feel the cranks "Double D" section go into the clutch assembly.
Install the supplied Doppler variator nut and tighten slowly while holding the clutch bell. At this point the variator
should spin freely inside the clutch bell. Some play in and out is okay.
Install belt and adjust engine spring. You are ready for some fun! If you have any questions I can be located at:[Bates]