The zipper 1484 big bore kit will give you 114 hp, add the performance cam and that will bring up to 120 hp. The cylinders are a thing of beauty if your a gear head like me with better finning. Of course I didn’t stop there I have the SDS electronic fuel injection and variable timing also by SDS. Not having a dyno available to me like the Zipper folks have, I can only guess another 5 hp or so.
Pulled out my W&B for the Kitfox 7, it’s 826lbs (nose dragger) with Grove gear, magnum whole airplane parachute, MGL 10” EFIS, a210 com, transp, and iPad.
Zipper makes a bigger bore kit but I still like looking out and seeing the wings in the right place.
btw: I have no stake in either company.
Kitfox 7 flying
I think there is a great argument for the Shock monster gear, but it is a trade off with cruise speed for sure, you will loose 7-10 mph depending on tires. The gear is far safer and can make a bad grove gear landing look good. It allows for a greater angle of attack on take off and landing because of the higher stance, but hurts the visibility out the front. The TK1 gear legs move the wheels forward a couple inches which really improves the ground handling making it very stable.
The TK1 gear legs and Shock monster shocks are 1.6 lbs lighter than the Grove spring gear. You can shave an additional 4.12 lbs off by using the Beringer wheels and brakes. If you are interested in the Airstreaks in a 26" but plan on using the Kitfox at the LSA gross weight of 1320 lbs than look at the Alaskan Bushwheel Ultralights, the 26" is 3.5 lbs lighter per tire than the Airstreaks. the 29" Ultralight is 6lbs lighter per tire than the Airstreak 29."
Just some ways to save weight.
Bryan
Project Kitfox
Bowen Aero LLC
Kitfox Model 5 Lycoming O-290 D powered
Building a Model 7 Apex powered
Redding, CA
http://www.youtube.com/c/ProjectKitfox
When I converted my old model IV-1050 from Bungee gear, ATV tires with Douglass wheels and Matco brakes to Grove Gear, wheels, brakes and 21-800/6 tires the net weight gain was:
12 pounds.
It does move the CG aft on the ground which puts more weight on the tail, for ground handling this helps, it also allows for much more aggressive braking. In flight it does move the CG very slightly forward. It is very close to the datum so it doesn't have a noticeable effect. I was skeptical but it really does handle much better.
Bryan
Project Kitfox
Bowen Aero LLC
Kitfox Model 5 Lycoming O-290 D powered
Building a Model 7 Apex powered
Redding, CA
http://www.youtube.com/c/ProjectKitfox
More weight behind your main wheels in theory should make the plane less stable with ground handling as the weight wants to swap ends. This is why tail draggers ground loop. The weight tries to swap ends. The more weight aft, the worse it it. I understand what you are saying about a longer coupled wheel base which does make the plane more stable. It's be interesting to find out where the sweet spot is.
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Josh Esser
Flying SS7
Rotax 914iS
AirMaster Prop
Edmonton, AB, CWL3
I've captured reported weights for some time now and as of now my very limited data base shows:
w/o outliers w/o outliers Model KF4 KF5 KF5 KF6 SS7 SS7 average 676 841 820 906 836 827 Max 793 1,013 890 906 963 878 min 560 777 777 906 736 763 sigma 76 69 35 0 56 33 count 5 9 8 1 19 16 The columns labels "w/o outliers" represent me taking out variants caused by what could be "scale dreaming" and heavy engine choices but still only makes a 9 pound difference for the SS7. BTW - when I converted to TK-1 shocks (only, not their gear) it cost 8 pounds.
See my build log at:http://www.mykitlog.com/lowandslow/