> >  >      > > > Hello every one You can try again and I hope with better

 >>       > > > luck.Some hi tech glitch in cyber space...??
 >>       > > > Let me know.please. Cheers John.
 >>       >
 >>       > John,
 >>       >
 >>       > I like the 3 piece housing very neat.
 >>       >
 >>       > Do you know what RPM the BMW coupling is rated for?
 >>       >
 >>       > Can you advise of the total all-up weight.
 >>       >
 >>       > In your original assessment did you find splash oiling
insufficient?
 >>       > Thanks
 >>       > George

 >>   Hello George!   According to BMW (9 to 10000rpm) although  I did not
 >>  see the specs on it! The weight of the PSRU
 >>  with the starter is 49 lbs.The flywheel with the coupling is 19 lbs.
 >>  While I was running tests;in the first 45 hrs I
 >>  just ran on slpash,and the temp.never went over 205 degrees! Then ,with
 >>  a nice spinner on the prop the temp. went up to
 >>  230 degrees. However with the prop pusher mode,the temp stayed at
 >>  205-degrees. I used 20w50 oil! With the oil from the
 >>  engine directly from the cooler temp. stays around 190 degrees!
 >>
 >
 >19 pounds is WAY too much weight for a rotary engine flywheel John.
 >
 >Paul Lamar

    I disagree, I had three torsional dampers brake on my Ross gearbox,
 one that went through the prop and the prop drove a piece through the
 wing so I installed a 18 lb flywheel and it eliminated the problem
 and as a side effect there was a very noticeable gain in power as the
 flywheel absorbs power pulses and gives that power back during the
 lull so I think it is worth its extra weight.
    Atkins had the same problem and installed to a flywheel and
 reported the same results.
   I also tried my cog belt without a a flywheel and didn't like the
 vibrations at certain rpm's so I installed a 16 lb flywheel and again
 there was a noticeable performance gain that was worth the extra
 weight.
   I have also noticed this in the off road cars that I have been
 around, a lot of people install light flywheels but you have a lot
 more torque with a heavy flywheel.

    Ken

There is no doubt that a heavy flywheel smoothes out the torque pulses.
It is the bigger hammer approach. On the other hand many airplanes are
flying successfully with the 3 or 4 pound flex plate alone. Tracy
Crook's damper plate works much better than the old BMW clutch disk
used by Ross. In your case you have a 5 bladed Warp Drive prop that probably
has a lot more rotational inertia than the average bear.

BTW I love those pictures you sent Ken. You lucky dog.

Paul Lamar

    The five blade warp drive only weighs in at 18 lbs and I am sure a
damper will work but if a heavy flywheel gives a better climb rate
than the extra weight is paying for it self.
  With the heavier flywheel I noticed that it lifted up on the step in
the water better and better climb performance and like I said Atkins
reported the same gain on his RV.
  Also Skip Gorman reported better performance on rotary boat engines
and said that there is no way he would run without a flywheel.

   Ken

I am surprised a heavy flywheel gives a better climb rate. In theory
there is no HP advantage. Less torsional vibration I'll buy. The rotary already has
a lot of rotational inertia what with the two nine pound cast iron
rotors and balance weights. Dave Atkins has never flown one of Tracy's 
gear boxes to compare. BTW Flywheel windage losses can make a difference
at 6000 to 9000 RPM. The stock flex plate has a few fins on it that
should be removed. 

Speaking of heavy flywheels take a look at this EngineAir V8. It was the only
way they could get the gear box to live with out a torsional
vibration damper. 

Paul Lamar



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