Getting an old kitfox IV speedster up and running!

[Hockeystud87]

tl:dr: I want to get a kitfox that's been sitting for 10 years that is in good condition ready to fly, what is your advice on how to do this?

So I have a question for the Kitfox owners in this group or anyone who knows about Kitfox's. I am currently in the process of getting my tail endorsement in a Cessna 140. Once I get signed off I would like to fly a Kitfox. My grandfather has a Kitfox IV Speedster that was built around 1992 with a 80 HP Rotax 912 carburetor motor, that runs on auto gas. He has over 500 hours of time on the frame it's self and my grandfather is a superb craftsman. It has been in a hanger for it's entire life and my grandparents take extremely good care of everything from their cars to tables and obviously their planes. Here's the question:

The plane has not flown in maybe 10 years, did a run up about 4-5 years ago. I want to get this plane ready to fly to hopefully get to spend more time flying with my now 90+ grandfather by flying my grandfathers aircraft with him, but I want to be safe obviously!

What are some key things I would need too look at? Do the diaphragms in the carb need replacing? Fuel lines? Essentially what would you do to get a plane that's been sitting for a while but still in really good condition ready to fly? Thanks for all the help!

Al with the kitfox.jpg

[tommg13780]

It looks like you have a "Speedster" there which is the Kitfox clipped wing version. That's the same version as I fly.

[Hockeystud87]

Yea you're right! I hear good things about them what motor and cruise speeds you get?

[tommg13780]

With the 912/80hp IVO ultralight Grd Adjust prop 110-115 mph at 5500rpm. Average climb solo around 1500@60mph. All speedster mods.

[Hockeystud87]

Dang it sounds like you have pretty much the exact same plane as the one we got. 1500 is crazy climb rates. Whats your opinion on the handling? I have about 100 hours total and maybe 8 in tail draggers. Are they any more difficult than a regular T-Dragger?

[Dusty]

I have been through his a few times myself.
Chech paperwork ad's etc.
If it's rubber and critical to safe operation REPLACE! Including bungees.
Check tank condition and do a flow test.
Don't rush,take your time and be thorough(she's waited 10 years already).
Plenty of ground running wont hurt,then get a LAME to do an inspection.

Well that's the Readers digest version!
I'm sure others will add points I have omitted.
Nice machine by the way

[Hockeystud87]

I have been through his a few times myself.
Chech paperwork ad's etc.
If it's rubber and critical to safe operation REPLACE! Including bungees.
Check tank condition and do a flow test.
Don't rush,take your time and be thorough(she's waited 10 years already).
Plenty of ground running wont hurt,then get a LAME to do an inspection.

Well that's the Readers digest version!
I'm sure others will add points I have omitted.
Nice machine by the way

Thats good advice, if anything it would be a great time with my grandfather trying to learn his plane. What did you think of the handling of your kitfox?

[av8rps]

That is a great story about wanting to get your Grandfathers Speedster going again, and flying with him. That looks like a great little Kitfox.

I really like how the Speedster flies, it is really a sporty, fun flying airplane. It is a very nice handling tailwheel airplane. If it doesn't feel that way, there is something wrong with the tailwheel set up (which can be a common problem, so again, if it feels difficult and hard to control, it's most likely the tailwheel set up, not you).

For cruise, a nicely set up Speedster with reasonable streamlining efforts should easily get 120+ mph for cruise. I flew the factory glow in the dark green 912ul Speedster with a crappy wood prop on it that was over pitched, and we were seeing nearly 135 mph TAS at 5300 rpm. I think it would have done better with a bit less pitch, as it couldn't even hit 5500 rpm wide open (which means it wasn't developing max HP). My experience with a 912 has shown that you will have the prop set best if you set it up to get about 5600-5700 rpm when wide open straight and level. Obviously your mileage may differ, but generally I think you will find those numbers to be pretty good.

Note; With the prop set as I suggested you will probably get less climb rate than TommG is seeing with his. But based on what he posted, I think he could add some pitch to his prop and actually get higher cruise with just a little less climb. He also is not using wheel pants, so that's also a few MPH less.

[Hockeystud87]

That is a great story about wanting to get your Grandfathers Speedster going again, and flying with him. That looks like a great little Kitfox.

I really like how the Speedster flies, it is really a sporty, fun flying airplane. You should easily get 120+ mph out of one for cruise. I flew the factory glow in the dark green Speedster with a crappy wood prop on it that was over pitched, and we were seeing nearly 135 mph TAS at 5300 rpm. I think it would have done better with a bit less pitch, as it couldn't even hit 5500 rpm wide open. My experience with a 912 has shown that you will have the prop set best if you set it up to get about 5600-5700 rpm when wide open straight and level. Obviously your mileage may differ, but generally I think you will find those numbers to be pretty good.

Note; With the prop set as I suggested you will probably get less climb rate than TommG is seeing with his. But based on what he posted, I think he could add some pitch to his prop and actually get higher cruise with just a little less climb.

Interesting information. I personally think anything over 1000 FPM is more than needed, so I'd prefer a faster cruise my self. We have the adjustable pitch prop for on the ground. So when we get it flying I might play with it and try and get a better cruise. isnt the Vne speed of a kit fox 135? I'm guessing the Speedster has a higher Vne

[av8rps]

The best advice I can give you about making sure the engine and airframe are safe is to befriend an experienced 912 Kitfox guy in your area and ask him to go over the airplane with you. The more eyes, the better.

I also think Dusty's advice was good, especially about replacing rubber parts.

And if you decide to adjust your prop pitch, use an electronic angle finder in the same place on each blade so you know they are all exactly the same.