> > >  > 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

Here is the 3D of the spline eliminator. Bearing and shaft seal not shown.
Might as well throw in a few more pictures of Ken's Coot. Here we
are on base leg to Ken's home airport. You can just see the blue nitrous oxide
bottle peeking out behind the pilots seat in the next pic.

Paul Lamar

    There will have to be a second non split sleeve and thrust collar
that will slide over the split collar to hold it together.
    This could also be used on a damper like Tracy's, just bolt it to the plate.

   Ken

The inner race on the thrust bearing serves the purpose of keeping
the split sleeves together.

Paul Lamar
 
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