Rotax upgrade

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Includes: Highlander, Escapade, Summit and SuperSTOL.
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gkremers
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Posts: 495
Joined: Sun Aug 08, 2010 8:06 am
Location: Michigan

Rotax upgrade

Post by gkremers »

I have been thinking about upgrading the 912ULS for a year or so. The Edge Performance Big Bore Cylinders seemed like the least intrusive path for me. On wheels and skis the standard 912ULS is perfectly fine. When she's on floats at max weight on a day with no wind it was taking a little longer to get off the water. It was OK but thought with a few more ponies I figured it couldn't hurt. The upgrade is supposed to push the HP to 114.I had a few weeks earlier this winter to dig in and install the Edge Performance kit. My plane has been flying for 5.5 years so I figured it was time to replace the rubber water lines and radiator hoses, had to drain the coolant anyway for the upgrade. I also replaced the fuel filter and bought 2 new fuel lines for Aircraft Specility with regulars AN fittings for the fuel pump. They supply the fuel line from the pump to the distribution block with the banjo fitting. The hoses are the new premium Integral Firesleeve. I also rebuilt the carbs and had a local Rotax mechanic do the inspection the reshim the gearbox. All in all it took about 3 weeks working on it after work and a few weekends. Edge Performance tells you in the documentation the main jets may need to be changed to get an optimal EGT. Through trial and error I ended up with #60 main jets. The plane has a 3 blade Wirlwind Razor prop, needed to dial in about 4 tenths of a degree more pitch. The top speed is up 9%, it didn't really expect that much on top end because the plane it pretty draggy anyway. The climb performance is really spectacular, really looking forward to getting her back on floats this spring.

A few pics below on the upgrade.
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Clark in AZ
Veteran Member
Posts: 356
Joined: Wed Oct 07, 2015 11:40 am
Location: Cave Creek, AZ

Re: Rotax upgrade

Post by Clark in AZ »

Excellent! Thanks for the report. Be sure to tell us how much different it is on floats!

Clark
Building SuperSTOL Kit 512
Cave Creek, AZ
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