Soft Start Conversion - flywheel or no flywheel

H. Paul Shuch is a Light Sport Repairman with Maintenance ratings for airplanes, gliders, weight shift control, and powered parachutes, as well as an independent Rotax Maintenance Technician at the Heavy Maintenance level. He holds a PhD in Air Transportation Engineering from the University of California, and serves as Director of Maintenance for AvSport of Lock Haven.

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ShawnM
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Re: Soft Start Conversion - flywheel or no flywheel

Post by ShawnM »

FastEddieB wrote:One test to see if spark is being generated is to hook up an inductive timing light. When mine were questionable, I bought one for about $30 and it confirmed no voltage in the spark plug wires. I was lucky my 2007-vintage modules failed during ROTAX's 2-for-1 special.

As an aside, normally one can check for spark by removing a spark plug and cranking with the plug grounded and looking for a spark (I did it yesterday troubleshooting a riding mower). I've been told that doing that with a ROTAX is a bad idea - if the ground is not firm its detrimental to the coils to try to fire to an open circuit. Maybe someone else can confirm this precaution.
The 2-for-1 special was a great deal and I don't think we'll ever see that again. It saved me a small fortune also. :mrgreen:

I have heard the same thing about removing a plug and checking for spark on a Rotax, DON'T DO IT !!!!!
Wm.Ince
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Re: Soft Start Conversion - flywheel or no flywheel

Post by Wm.Ince »

FastEddieB wrote:I've been told that doing that with a ROTAX is a bad idea - if the ground is not firm its detrimental to the coils to try to fire to an open circuit. Maybe someone else can confirm this precaution.
Quite a while back, I heard that same information . . . cranking the engine that way is a bad thing.
Bill Ince
LSRI
Retired Heavy Equipment Operator
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drseti
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Re: Soft Start Conversion - flywheel or no flywheel

Post by drseti »

I installed a pair of soft-start modules in June, along with the Y cable (and no flywheel change). Cost around $2k, and required only about an hour of labor. Super easy start now. No kickback, vibration, or stumbling. I wish I had done this years ago!
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof H Paul Shuch
PhD CFII DPE LSRM-A/GL/WS/PPC iRMT
AvSport LLC, KLHV
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AvSport.org
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ShawnM
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Re: Soft Start Conversion - flywheel or no flywheel

Post by ShawnM »

I did mine years ago and was also amazed at the difference in start up and how much smoother it was. It's a simple swap but it's not cheap, as with anything Rotax. :mrgreen:
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drseti
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Re: Soft Start Conversion - flywheel or no flywheel

Post by drseti »

ShawnM wrote:It's a simple swap but it's not cheap, as with anything Rotax. :mrgreen:
If you think Rotax is expensive, you should try maintaining a Lycoming!
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof H Paul Shuch
PhD CFII DPE LSRM-A/GL/WS/PPC iRMT
AvSport LLC, KLHV
[email protected]
AvSport.org
facebook.com/SportFlying
SportPilotExaminer.US
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bitten192
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Re: Soft Start Conversion - flywheel or no flywheel

Post by bitten192 »

drseti wrote:I installed a pair of soft-start modules in June, along with the Y cable (and no flywheel change). Cost around $2k, and required only about an hour of labor. Super easy start now. No kickback, vibration, or stumbling. I wish I had done this years ago!
ditto. I did mine recently. No flywheel conversion. Starts/runs great!
Ernie
CFI, LSRM-A
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