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[lancaironline.net] WEIRD_PORT 0.001 Uses non-standard port number for HTTP --000000000000011f76062b71c322 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Pretty well, since the MT cars don't have them. ;-) MT has a 20 lb hunk of cast iron (includes the balance weight for that end) with a ring gear on it. On Sat, Jan 11, 2025 at 10:43=E2=80=AFAM Marc Wiese cardmarc@charter.net < flyrotary@lancaironline.net> wrote: > So these cracked flex plates are ONLY on AT equipped cars? Wonder how the > MT plates fare? > M > Sent from my iPhone > > On Jan 11, 2025, at 10:38=E2=80=AFAM, David COOK hoursaway1@comcast.net < > flyrotary@lancaironline.net> wrote: > > =EF=BB=BF > I personally removed two eng. from the RX7's, heard them start and run, > drove one, both had cracks in flex plates. David > > On 01/10/2025 11:50 PM EST Charlie England ceengland7@gmail.com < > flyrotary@lancaironline.net> wrote: > > > They do crack in the car, regardless. > > On Fri, Jan 10, 2025 at 10:36=E2=80=AFPM Stephen Izett stephen.izett@gmai= l.com < > flyrotary@lancaironline.net> wrote: > > Hi there Dave > > I understood the torque converter was driven from the flex plate. > Can someone confirm how power is transferred from the Eccentric to the > torque converter? > > Steve Izett > > On 11 Jan 2025, at 9:35=E2=80=AFam, David Leonard wdleonard@gmail.com < > flyrotary@lancaironline.net> wrote: > > in the car, the flex plates are only used to carry the torque from the > starter and are not designed to transmit the output of the engine. in our > setups. We have adapted this flex plate to transmit the entire output of > the engine which it apparently is not up to. > > I had my rd1-b seize up a bearing during a race at Reno which may have > been due to gyroscopic forces, but I think the flex plate issue just need= s > to be fixed by replacing all the flex plates with proper flywheels. > > Dave Leonard > > On Fri, Jan 10, 2025, 1:45=E2=80=AFAM Le Roux Breytenbach > breytenbachleroux@gmail.com wrote: > > What i can rember was this also a topic on the late Paul L group > discussion. > Maybe Dave Leonard can chime in - think more that it was gyroscopic force= s > that craked the plates > Maybe i can find the photos and topic in my old mails > > Sent from my iPhone > Le Roux Breytenbach > > On 10 Jan 2025, at 08:13, Andrew Martin andrew@martinag.com.au < > flyrotary@lancaironline.net> wrote: > > Maybe some of the cracking flexplates are resulting from starting issues, > the starter motor can hammer the ring gear if not meshing correctly or if > engine misfires on start. may explain why so many flexplates come > pre-cracked from the wreckers. > > Andrew > > > > > On Fri, 10 Jan 2025 at 11:32, Stephen Izett stephen.izett@gmail.com < > flyrotary@lancaironline.net> wrote: > > Hi M > > I was wondering the same thing. > > What I discovered first of all was that flex plates are designed to flex > (funny that) and cracking is not limited to our setup. > There are companies that specialise in stronger flex plates, particularly > for modified and higher horsepower engines. > > Since our engines are being used at a higher horsepower per unit time and > therefore higher stress (assumption) perhaps our setup could be likened t= o > race applications. > But then our hours of use would be significantly lower (assumption) than > an average vehicle, but perhaps not a race application. > Is the cracking we are seeing consistent with race applications? But they > dont race automatics, do they? > > So my take on this is that perhaps the flexing of the plate in our setup > is to some extent higher than OEM. > > Our options seem to be: > 1. Replacing the OEM flex plate with a stronger part. Steve B being the > latest going down that track and in his case also removing the rubber > isolation in the process. > 2. Connect direct to the eccentric shaft and therefore taking the stress > off the Flex Plate doing away with the damping mechanism which Tracy did, > and perhaps is still doing. Would be real nice to know. > > Like M, I would appreciate hearing what others know or are thinking or > doing. > > Steve Izett > > > > > > > > > > > > > > On 10 Jan 2025, at 2:15=E2=80=AFam, Marc Wiese cardmarc@charter.net < > flyrotary@lancaironline.net> wrote: > > > > Has the cause of these cracks been uncovered, and if so, what is the > current thinking on it? An AL racing plate? > > M > > Sent from my iPhone > > > >> On Jan 9, 2025, at 1:31=E2=80=AFAM, Steven W. Boese SBoese@uwyo.edu < > flyrotary@lancaironline.net> wrote: > >> > >> Steve, > >> > >> I didn=E2=80=99t see the cracks prior to disassembly and doubt that th= ey could > have been seen on the counterweight side very well -if at all- when > assembled. > >> > >> I replaced the Flexplate with a steel flywheel about a year ago. Sinc= e > then, I replaced the four rubber dampers with machined aluminum discs > giving a solid connection and then dynamically balanced the system. This > was done because maintaining a dynamic balance wasn=E2=80=99t possible wi= th the > dampers. Only a few hours of flight have occurred in this configuration = so > far and there has been no indication of problems resulting from this > change. > >> > >> Steve Boese > >> > >>> On Jan 8, 2025, at 11:03=E2=80=AFPM, Stephen Izett stephen.izett@gmai= l.com < > flyrotary@lancaironline.net> wrote: > >>> > >>> =E2=97=86 This message was sent from a non-UWYO address. Please exerc= ise > caution when clicking links or opening attachments from external sources. > >>> > >>> > >>> Hi Steve > >>> > >>> Is this recent then? > >>> > >>> I=E2=80=99m not able to get to my aircraft at present to check my fle= x plate > which has probably seen 50 hours of service. > >>> > >>> Was it possible to see these cracks assembled? > >>> > >>> I would appreciate your reflections on Tracys latter choice to remove > the damper, and particularly when using a timber/glass prop such as an MT= . > >>> > >>> It would be great to have an update and current info from Tracy > regarding his no damper hours if anyone can contact him. > >>> > >>> Very helpful, thanks again Steve > >>> > >>> Steve > >> > >> -- > >> Homepage: http://www.flyrotary.com/ > >> Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > > > > > > > -- > > Homepage: http://www.flyrotary.com/ > > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > --000000000000011f76062b71c322 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Pre= tty well, since the MT cars don't have them. ;-)

MT has a 20 lb hunk of cast iron (includes=C2= =A0the balance weight for that end) with a ring gear on it.

=
On Sat, Jan 11, 2025 at 10:43=E2=80=AFAM Marc Wiese cardmarc@charter.net <flyrotary@lancaironline.net> wrote:
= So these cracked flex plates are ONLY on AT equipped cars? Wonder how the M= T plates fare?
M
Sent from my iPhone

On Jan 11, 2025, at 10:38=E2=80=AFAM, David COOK hoursaway1@comcast= .net <flyrotary@lancaironline.net> wrote:

=EF=BB=BF =20 =20 =20 =20
I personally remove= d two eng. from the RX7's, heard them start and run, drove one, both ha= d cracks in flex plates. David
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On 01/10/2025 11:50 PM EST Charlie England ceengland7@gmail.com <flyrotary@lancaironline.ne= t> wrote:
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They do crack in the car, regardless.
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On Fri, Jan 10, 2025 at 10:36=E2=80=AFPM Stephen Izett stephen.izett@gmail.com &= lt;flyrota= ry@lancaironline.net> wrote:
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Hi there Dave=20
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I understood the torque converter was driven from the flex plate.=C2= =A0
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Can someone confirm how power is transferred from the Eccentric to t= he torque converter?
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=C2=A0
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Steve Izett
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On 11 Jan 2025, at 9:35=E2=80=AFam, David Leonard wdleonard@gmail.= com <flyrotary@lancaironline.net> wrote:
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in the car, the flex plates are only used to carry the torque fr= om the starter and are not designed to transmit the output of the engine. i= n our setups. We have adapted this flex plate to transmit the entire output= of the engine which it apparently is not up to.=C2=A0=20
=C2=A0
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I had my rd1-b seize up a bearing during a race at Reno which m= ay have been due to gyroscopic forces, but I think the flex plate issue jus= t needs to be fixed by replacing all the flex plates with proper flywheels.= =C2=A0
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=C2=A0
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Dave Leonard=C2=A0
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On Fri, Jan 10, 2025, 1:45=E2=80=AFAM Le Roux Breytenbach breytenbachleroux@gmail.com <flyrotary@lancaironline.net> wrote:
=20
=20
What i can rember was this also a topic on the late Paul L gro= up discussion.=20
Maybe Dave Leonard can chime in - think more that it was gyro= scopic forces that craked the plates
=20
Maybe i can find the photos and topic in my old mails
=20

=20
Sent from my iPhone=20
Le Roux Breytenbach=C2=A0
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Maybe some of the cracking flexplates are resulting from = starting issues, the starter motor can hammer the ring gear if not meshing = correctly or if engine misfires on start. may explain why so many flexplate= s come pre-cracked from the wreckers.
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Andrew
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On Fri, 10 Jan 2025 at 11:32, Stephen Izett stephen.iz= ett@gmail.com <flyrotary@lancaironline.net> wrote:
=20
Hi M

I was wondering the same thing.=20

What I discovered first of all was that flex plates a= re designed to flex (funny that) and cracking is not limited to our setup.= =20
There are companies that specialise in stronger flex = plates, particularly for modified and higher horsepower engines.

Since our engines are being used at a higher horsepow= er per unit time and therefore higher stress (assumption) perhaps our setup= could be likened to race applications.
But then our hours of use would be significantly lowe= r (assumption) than an average vehicle, but perhaps not a race application.
Is the cracking we are seeing consistent with race ap= plications? But they dont race automatics, do they?

So my take on this is that perhaps the flexing of the= plate in our setup is to some extent higher than OEM.

Our options seem to be:
1. Replacing the OEM flex plate with a stronger part.= Steve B being the latest going down that track and in his case also removi= ng the rubber isolation in the process.
2. Connect direct to the eccentric shaft and therefor= e taking the stress off the Flex Plate doing away with the damping mechanis= m which Tracy did, and perhaps is still doing. Would be real nice to know.

Like M, I would appreciate hearing what others know o= r are thinking or doing.

Steve Izett












> On 10 Jan 2025, at 2:15=E2=80=AFam, Marc Wiese <= a href=3D"mailto:cardmarc@charter.net" rel=3D"noopener" target=3D"_blank">c= ardmarc@charter.net <flyrotary@lancaironline.net> wrot= e:
>=20
> Has the cause of these cracks been uncovered, an= d if so, what is the current thinking on it? An AL racing plate?
> M
> Sent from my iPhone
>=20
>> On Jan 9, 2025, at 1:31=E2=80=AFAM, Steven W= . Boese SBoese@uwyo.edu <flyrotary@lancaironline.net> wrote= :
>>=20
>> Steve,
>>=20
>> I didn=E2=80=99t see the cracks prior to dis= assembly and doubt that they could have been seen on the counterweight side= very well -if at all- when assembled.
>>=20
>> I replaced the Flexplate with a steel flywhe= el about a year ago.=C2=A0 Since then, I replaced the four rubber dampers w= ith machined aluminum discs giving a solid connection and then dynamically = balanced the system.=C2=A0 This was done because maintaining a dynamic bala= nce wasn=E2=80=99t possible with the dampers.=C2=A0 Only a few hours of fli= ght have occurred in this configuration so far and there has been no indica= tion of problems resulting from this change.
>>=20
>> Steve Boese
>>=20
>>> On Jan 8, 2025, at 11:03=E2=80=AFPM, Ste= phen Izett stephen.izett@gmail.com <flyrotary@lancaironlin= e.net> wrote:
>>>=20
>>> =E2=97=86 This message was sent from a n= on-UWYO address. Please exercise caution when clicking links or opening att= achments from external sources.
>>>=20
>>>=20
>>> Hi Steve
>>>=20
>>> Is this recent then?
>>>=20
>>> I=E2=80=99m not able to get to my aircra= ft at present to check my flex plate which has probably seen 50 hours of se= rvice.
>>>=20
>>> Was it possible to see these cracks asse= mbled?
>>>=20
>>> I would appreciate your reflections on T= racys latter choice to remove the damper, and particularly when using a tim= ber/glass prop such as an MT.
>>>=20
>>> It would be great to have an update and = current info from Tracy regarding his no damper hours if anyone can contact= him.
>>>=20
>>> Very helpful, thanks again Steve
>>>=20
>>> Steve
>>=20
>> --
>> Homepage:=C2=A0 http://www.flyrotary.com/
>> Archive and UnSub:=C2=A0 =C2=A0http://mail.lancaironline.net:81/lists/flyrotary/List.htm= l
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> --
> Homepage:=C2=A0 http://www.flyrotary.com/
> Archive and UnSub:=C2=A0 =C2=A0http://mail.lancaironline.net:81/lists/flyrotary/List.html



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Homepage:=C2=A0 http://www.flyrotary.com/
Archive and UnSub:=C2=A0 =C2=A0http://mail.lancaironline.net:81/lists/flyrotary/List.html
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