> George Lendich wrote:

 Paul,
 I'm out of my depth here mate - as usual but my flexplate has a counter
 weight it's bolted to and weighs 3879 grams all up
 or 8.5 lbs.

 However having seen the BMW type dampers they do seem heavy but very robust.

 I'm wondering  what the all up weight of Tracy's Flexplate and damper is,
 perhaps there isn't much between Tracy's and Ken's 16
 lbs.

 I'm now wondering what an ideal all up flex-plate and damper might be !!?
 George (down under)

Here is something Power Sport came up with.
Sorry about the out of focus pic. Don Dunbar is using a rubber
coupling that looks
real interesting. I would wait and see how it idles however :) Might be a bit
too stiff. One can always drill holes in the rubber to soften it up a bit.
Freeze it first.

The real advantage of a rubber coupling is there is no spline hence there is
no slop to wear out the spline.

Paul Lamar

   Hey George maybe you missed my point that I would run the 16 lb
flywheel and a damper similar to Tracy's or something else so I would
be adding the 16 lbs as I am just replacing the flex plate, this is
what I did with the Ross setup when I was blowing the dampers.
  When I get by the airport I will shot a photo of the busted damper I
have there from the Ross redrive.
  Also I think that if anyone is still running a Ross with the spring
damper it may be worth trying one of those PYI dampers as the spring
damper has is known to fail and the PYI should be a direct
replacement.

  Hey Paul I would love to get rid of the spline on the damper but I
don't see how to make it work as if there is a flange on the sun gear
shaft to bolt to the damper you won't be able to get that flange
through the thrust bearings, oil seal or the housing.
  Also while we are in the that aria what is the best way to attach
the sun gear to the pilot shaft, Ross said that he made it a press
fit and then pined it but I don't recall seeing any pins and I don't
have the Ross redrive back to him and of corse I never got it back.

   Ken

I have a shot of Ken's busted damper :) So far we have had no other reports
of busted Ross dampers but then very few people are routinely running nitrous through
their engines like Ken does and use an 18 pound prop :) So far Tom Parkes is 
reporting no problems with his damper and he is feeding a turbo 3 rotor through 
it. I will admit they rattle the heck out of the gear box if you let them 
idle below 2000 engine RPM.

Damper is a misnomer with these things as the springs give back all the  pulse
energy put in them. Rubber on the other hand heats up and dissipates some of
the energy. Tracy claims he keeps making the bushings softer and softer
and it keeps working better and better. I don't know how long ago he stopped
doing that and settled on a final hardness :)

The helical gear thrust bearing ID and seal ID must be larger than the sun gear OD
unlike that shown on this drawing. Then you use a split keeper. Something like a 
valve stem keeper to feed the gear thrust load into the bearing. I am sure Don 
Dunbar found that out already when he first tried to put his together :) 

I'll do a 3D of this trick if you need one.

I had Tracy just press fit my sun gear on the shaft. My theory (to be tried on the dyno
and not in the air) is if it slips it will friction weld itself to the shaft.

Here too is a picture of me and Ken getting ready to go down and land in the river.

Paul Lamar
 
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