Would a model 7 with an 80 hp engine fly or would it be a total turd?
Would a model 7 with an 80 hp engine fly or would it be a total turd?
TJay Larsen
M1 Custom
Jabiru 2200 85hp
It depends on the weight
A model 7 is generally 200 pounds heavier than a model 4 which fly ok with a 200 pound passenger.
Put the same passenger in a 7 with an 80hp and the performance would be suboptimal at best.
The 7 needs more power than a 4 due to weight.
My zippered (105hp) 4 with cabane gear and bigger tyres outperformes my brothers 914 powered 7 with grove gear and std tyres in everything but climb which isn't a startling difference .
It wouldn't be a total turd if you could keep the weight under 800lbs, which is very hard to do. It would be marginal at best.
But there are better options...
Imho, the minimum Rotax for the 7 would be the 100hp 912uls, IF you could keep the weight under control. (as close to 800lbs as you can). Still kind of marginal especially if you're on the heavy side.
If I were to build a ss7 kit, I would find a used kit (not built yet). Then find a mid 2006 or newer 912uls (has the heavy-duty case) and install the high-power, Zipper big bore kit. The 1484cc kit will give you 114hp and with the optional cam you can get to 120hp!
Theoretically, let's say about 8k for a used engine, 4.4k for the big bore kit (5.2k for Hal to do it)
You have 114hp for about 12-13k. A new E-prop, spinner, 2" extension and accessories and I bet you'd could be under 18k. Now were talking!
A new 912uls is approx. 22.3k and a new 912is is about 30k, and the 915is is 43.7k.
With prices/tariffs going wonky as of late, you might be paying a lot more...
For me, that's not going to fly!
Zipper Big Bore | More Horsepower for your Rotax 912 Engine
Last edited by bbs428; 04-13-2025 at 05:12 PM.
"Somebody said that carrier pilots were the best in the world, and they must be or there wouldn't be any of them left alive." Ernie Pyle
Brett Butler
Flying: N46KF, 1998 Model 5 Outback, 912ul 110hp, G3x with 2 axis a/p, Beringer wheels & brakes, SS7 firewall forward, NR prop, Custom paint