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Slyfox
01-19-2009, 05:19 PM
WOW! is all I can say. I did my ground runs, with the 69 inch IVO ultra light prop, I couldn't static run it, it kept over reving. I was a little hesitant to fly it, but I found that running up the engine I had troubles holding the brakes, I figured she would fly. I ended up at the beginning of the runway and took the long one. Now the weather was clear from the end of the runway east, to the west was not so good. Temp, 28 lovely degrees f. Did one more runup and decided it was time to do this. I called for clearance for takeoff and went out on the runway. I slowely pushed in the throttle and away I went, I lifted the tail and very quickly went up. I wasn't paying attention to anything but flying the plane and was super suprised at how straight up I was going. Than I looked down and saw the vsi at about 2000, than I looked at the ias and it was at about 65mph. Cool. I was up to 800 ft after about 2000ft of runway and turning for pattern work. Straight flight, I got 120ias no problem with 108kts gps, landings were very predictable, just like usual. I sure got speed fast. After not flying for 2 months, it sure was a total treat.

Oh another thing I got to try out. My heated vest, I can't emagine not having it. Low setting is all that is needed even at 28degrees.

DesertFox4
01-20-2009, 12:03 PM
Sounds like your engine swap was a success Steve. Congrats. The preliminary numbers sound like quite an improvement. Always a winning combination, a light aircraft with a light strong engine. :D Have fun getting re-acquainted with your Kitfox and remember you are back in test pilot mode for a few hours so keep a close watch on everything and fly accordingly. Good luck and keep us posted.

Slyfox
01-20-2009, 12:36 PM
you are so right, test mode. Funny thing, there was no leaks until I looked under the panel. The fuel filter was leaking????? I changed it right away. I had to put in a few ounces of coolant. Got to get back up again, waiting on the weather.

RandyL
01-20-2009, 12:50 PM
Wow, congrats Steve!

I don't want to start thread creep, but what is the accepted best practice for Rotax 912 break-in? I can tell you all about Lycomings but am new to the Rotax thing.

Slyfox
01-20-2009, 02:37 PM
[quote=If you were over revving the 912-S on the ground, what kind of RPM's were you getting on your speed runs ? For most LSA with non inflight adjustable prop, the 912-S should be seeing 5200 RPM or even less for static and climb. If you were getting over 5800 RPM static with a non inflight adjustable prop , your prop adjustment was way way off. That would result in grossly overspeeding the engine at cruise, and really hurt your cruise speeds in general. There is very little to be gained by ever going over 5500 RPM, the amount of extra power your engine will generate at 5800 RPM is minisucle compared to 5500, and wear and stress on the engine goes way up. If you want that engine to last a long time, prop it so that you are never over 5500 RPM, you will have the added benefit of faster and more efficient cruise also with more pitch on the prop.

The 912-S is a great engine, I would hate to see you trash it right off the bat.

[/quote]

I totally agree with you on what you say. But, with the ultra light prop and the uls engine, the prop will cavitate. You can use it as long as you slowely give it power and don't let it flex out, so to speak. I watched things really carefully and know the feel of an engine on over rev. So with a slow throttle increase on the ground with course pitch on the prop(inflight adjustable) I managed to get a good ground run. I would not recommend somebody that isn't familiar with the set up at all. When I took off I kept it under 5600 rpm all the time, never went over that. I got my high speed run at 5600rpm and managed to increase the prop via switch on the dash to do this. I was only over 5800 on the ground for not even a second, as soon as it went up there I throttled back. I was in safe zone the entire time. What am I going to do with this, I ordered the medium prop. Only 10 pounds more, my plane weighs empty at 650 so I think it will be ok. Than I ordered the aluminum cooler, so some weight lost there.

Slyfox
01-20-2009, 03:42 PM
Randy,
I couldn't find anything either. I put in from the start the aeroshell oil recommended by Rotax. I will run that for 15 hrs and than change the oil. I'm going by my old school and varying the throttle and watching the temps and oil pressure. Although higher temps than the old engine, could be a problem with sensor compatibility issues with the westech guages and the rotax sensors, but I'm still within limits. I will be check those here shortly for accuracy. Other than that this is a close tolerance motor and I'm told that it doesn't need break in like the lycomings.

Of course if anybody has good knowledge on breakin on these engines, please but in.

Slyfox
01-21-2009, 08:27 AM
I got the one from tour master, the one with no sleeves. I put it under a north face coat with short sleeve tee shirt. I hooked up the wiring so it comes direct off the battery. I cut the wire harness just after the fuse and put in 18g wire and than picked it up again at the harness to the vest. Than the wire hookup is just on the left side of the seat against the door. I get in, sit down, I grab the wires and hook up and than do my normal stuff for flight. After I start up I turn on the low setting and forget about it. It comes on real quick.