Continental 0-200D vs. Rotax 912 uls for Kitfox

TreeTopFlyer83

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TreeTopFlyer83
Was wondering if any of you folks have had any experience with either engine. Not necessarily in a Kitfox but something similar? Obviously they both generate 100hp but the Continental is heavier by roughly 50 lbs. Thoughts on either one of these engines going into the Kitfox STI? Or it's possible that we do a bigger engine with the Titan X340 or Rotax 912is sport. Thoughts ladies and gents? Thanks any advance for any information or feedback.
 
I fly a 914 rotax turbo. Is that an option for you? Runs on 100LL or mogas, and it's light and powerful.

Have you had any problems with the turbo? It could be an option. I'm trying to stay somewhere around 75K total.
 
RED BRICK dependability
I haven't heard of Rotax powered planes falling from the sky. The O-200 is a reliable engine, but I haven't heard of issues with Rotax either.

Is there a difference in phase 1 testing with the Rotax?
 
I haven't heard of Rotax powered planes falling from the sky. The O-200 is a reliable engine, but I haven't heard of issues with Rotax either.
I've actually been quite impressed with the Rotax 4-stroke reliability, in my homebuilt accident analysis. Here's some statistics from my personal database of homebuilt accidents (1998-2017):
______Type of Engine_____|_Total Accidents_|_% Engine Failures_|
___Traditional Engines___|_______1900______|_______17.8%_______|
_______Auto Engines______|_______447_______|_______43.8%_______|
__Non-Cert Four Strokes__|_______472_______|_______17.4%_______|
_______Two-Strokes_______|_______414_______|_______35.7%_______|

This data is for fixed-wing homebuilts only. "Traditional Engines" are the classic certified engines, "Non-Cert Four Strokes" includes the Rotax 912 and 914 series as well as other engines like the Jabiru.

The "% Engine Failures" is the percentage of total accidents to aircraft involving those types of engines, in which loss of engine power was the main driver for the accident. It doesn't include pilot-induced engine failures (e.g., fuel issues or system management) but does include the cases where the cause of the engine failure was not determined.

By these results, the reliability of the non-certified four strokes is about the same as the traditional engines.

Looking at *just* the Rotax 912, the results are even better. The total number of accidents drops to about 340, but only about 15% were due to problems with the engine.

Ron Wanttaja
Still hoping to get the Xenforo table functions enabled
 
I've actually been quite impressed with the Rotax 4-stroke reliability, in my homebuilt accident analysis. Here's some statistics from my personal database of homebuilt accidents (1998-2017):
______Type of Engine_____|_Total Accidents_|_% Engine Failures_|
___Traditional Engines___|_______1900______|_______17.8%_______|
_______Auto Engines______|_______447_______|_______43.8%_______|
__Non-Cert Four Strokes__|_______472_______|_______17.4%_______|
_______Two-Strokes_______|_______414_______|_______35.7%_______|

This data is for fixed-wing homebuilts only. "Traditional Engines" are the classic certified engines, "Non-Cert Four Strokes" includes the Rotax 912 and 914 series as well as other engines like the Jabiru.

The "% Engine Failures" is the percentage of total accidents to aircraft involving those types of engines, in which loss of engine power was the main driver for the accident. It doesn't include pilot-induced engine failures (e.g., fuel issues or system management) but does include the cases where the cause of the engine failure was not determined.

By these results, the reliability of the non-certified four strokes is about the same as the traditional engines.

Looking at *just* the Rotax 912, the results are even better. The total number of accidents drops to about 340, but only about 15% were due to problems with the engine.

Ron Wanttaja
Still hoping to get the Xenforo table functions enabled

Thanks for the data!
 
Has anyone done the research on the difference in insurance rates for equal aircraft with certified and non- certified engines ?
 
Has anyone done the research on the difference in insurance rates for equal aircraft with certified and non- certified engines ?
I've always had the (perhaps unwarranted) assumption that insurance companies were at least as smart as I am. Hence the kinds of things I discover, they're already aware of. Over a quarter of the RV-9s involved in accidents, for instance, had auto engines. I doubt the insurance companies haven't noticed this and undoubtedly it is reflected in their rates.

It would be interesting to compare the rates offered for an RV-12 with a certified Rotax 912, vs. one with a non-certified one. I'd guess, in this case, the rates are probably the same.

Ron Wanttaja
 
I was once told, “the Rotax 912 is the aviation equivalent to a Honda motorcycle engine.” That’s an impressive claim.
That is not true.
It has proven to be much better than that.
Power to weight ratio cannot be beat.
Reliability and performance awesome.
Easy to work on, even the carbureted version.
 
As much as it pains me to say I would go rotax. They sound terrible but truth is they have proven to be exceptionally reliable and good performers. I know guys who have let them sit for years and never have issues bringing them back to life.
 
IMO, for a lightweight airplane like the Kitfox, the Rotax is the way to go.
I am not up on the current kitfox’s but was working at the Kitfox factory when they first tried the Rotax in it. It was a huge improvement over the KFM engine. They were just starting installing the continental? Engine in it when I left so never really got to compare the two.
Brian
 
The Rotax is gonna be spinning at twice the rpm for a "sporty" cruise power setting. Some may prefer the more relaxed feel of the Conti.
 
I was told by a Kitfox owner that his kitfox did not have enough rudder for a 0-200-
 
As much as it pains me to say I would go rotax. They sound terrible but truth is they have proven to be exceptionally reliable and good performers. I know guys who have let them sit for years and never have issues bringing them back to life.

They sound awesomely quiet.

A typical Continental , even in a c150 sounds like a damn ww 2 bomber compared to a rotax plane ...
 
What do you get for your 50 pounds? (Other than 50 pounds.)
The Rotax 912 is significantly more expensive, last I checked. So, if one can sacrifice 50 lbs of useful load, then the option of O-200-D looks rather attractive. Unfortunately, O-200-D also burns more gas, so the financial savings over the lifetime of the engine may not be as great. But then again, throttle back a little.
 
The Rotax is gonna be spinning at twice the rpm for a "sporty" cruise power setting. Some may prefer the more relaxed feel of the Conti.
Bear in mind, the Rotax is a “geared” engine. The engine may be spinning faster, but the resultant prop RPM is comparably the same.
 
i have a little time behind an 0-200 (Cessna 150) and in front of a Rotax 912 (light sport trike). I'd go with the Rotax, it's lighter, quieter, and smoother. If I were building something in the Kitfox size range, I'd make sure the fuel system is alcohol friendly, and run E10 premium mogas.
 
Either the Rotax 912 ULS or iS should be your choice (if you can afford the extra cost, a Rotax is a no-brainer). You can burn 91-93 octane auto gas (ethanol is NOT an issue with Rotax), it's lighter, quieter, smooth-running, and damn-near bullet-proof. The main downside is the scarcity of certified Rotax mechanics. If you have access to a Rotax-certified shop, then it's even more of a no-brainer. Also, you can take Rotax maintenance classes that will allow you to perform maintenance and inspections yourself. Oh, and oil capacity is a mere 3 liters. Makes oil changes a breeze.
 
I was once told, “the Rotax 912 is the aviation equivalent to a Honda motorcycle engine.” That’s an impressive claim.
That is not true.
It has proven to be much better than that.
Power to weight ratio cannot be beat.
Reliability and performance awesome.
Easy to work on, even the carbureted version.
Actually, the "aviation equivalent to a Honda motorcycle engine" is a huuuuuuuuuge compliment.
 
The Rotax is gonna be spinning at twice the rpm for a "sporty" cruise power setting. Some may prefer the more relaxed feel of the Conti.
You really don't notice that. Prop speeds are substantially lower.

I have no real experience with the O-200, maybe a hundred or so hours with Lycomings before the Rotax. I have been flying a Rotax 912ULS in an RV-12 for the past 5 years. During that time, my engine "problems" have consisted of one instance of a spark plug boot coming loose, caught during run-up (10 minutes to de-cowl and fix, $5 to replace that boot at the next annual). I've probably added a grand total of a pint or so of oil between changes during that time... it just does not burn oil. Winter and hot starts are a complete non-event. Burns 91 octane MOGAS, or AVGAS if necessary.

Maintenance during the annual CI hasn't been bad. Fuel lines had to be replaced during the first annual - the original rubber hoses are a 5-year item. I spent a little extra for firesleeved conductive Teflon hoses, which I'll never need to replace again. The coolant lines are still a 5-year item, so there's a few extra hours every 5 years. I bought a gallon of coolant (automotive antifreeze) that will probably last until I die. Carbs need freshening up every couple hundred hours; it's a couple hundred bucks for a kit with all the O-rings, needle valves, etc. needed. Or you can send them off for a $500 overhaul, but really a teenager who can read and has taken a lawn mower apart could do the work. New plugs are under $3 each, and you can buy them anywhere. During all of the maintenance I've done, I have found that if you follow the Rotax service manual to the letter, everything just works - perfectly, the first time. No "tweaking" required.

Operationally, the engine has been a joy. No drama, no hassle. Starts are effortless and reliable. No priming, no manual mixture control, no carb heat. Good cabin heat in winter. It's nice and smooth. The tach reads high compared to what you're used to seeing -- takes a couple of flights to get used to that. I cruise between 5000 and 5300 RPM usually. That means a prop speed of roughly 2000 - 2200 RPM.

TBO is 2,000 hours, and I get the sense it will make it there with no problem. Unlike a Conti or Lycoming, my understanding is that during a major overhaul the crankshaft will get replaced, but not the cylinders. I don't know, with 450 hours on the engine I doubt I'll need to worry about it.

There are tens of thousands of Rotax engines flying, and they have been in the field for decades. This is not new and exotic technology. Rotax has been very, very attentive to the engines, with tons of freely available documentation (light and heavy repair manuals, service instructions, etc). and changes over the years to improve reliability and longevity.
 
You really don't notice that. Prop speeds are substantially lower.

I have no real experience with the O-200, maybe a hundred or so hours with Lycomings before the Rotax. I have been flying a Rotax 912ULS in an RV-12 for the past 5 years. During that time, my engine "problems" have consisted of one instance of a spark plug boot coming loose, caught during run-up (10 minutes to de-cowl and fix, $5 to replace that boot at the next annual). I've probably added a grand total of a pint or so of oil between changes during that time... it just does not burn oil. Winter and hot starts are a complete non-event. Burns 91 octane MOGAS, or AVGAS if necessary.

Maintenance during the annual CI hasn't been bad. Fuel lines had to be replaced during the first annual - the original rubber hoses are a 5-year item. I spent a little extra for firesleeved conductive Teflon hoses, which I'll never need to replace again. The coolant lines are still a 5-year item, so there's a few extra hours every 5 years. I bought a gallon of coolant (automotive antifreeze) that will probably last until I die. Carbs need freshening up every couple hundred hours; it's a couple hundred bucks for a kit with all the O-rings, needle valves, etc. needed. Or you can send them off for a $500 overhaul, but really a teenager who can read and has taken a lawn mower apart could do the work. New plugs are under $3 each, and you can buy them anywhere. During all of the maintenance I've done, I have found that if you follow the Rotax service manual to the letter, everything just works - perfectly, the first time. No "tweaking" required.

Operationally, the engine has been a joy. No drama, no hassle. Starts are effortless and reliable. No priming, no manual mixture control, no carb heat. Good cabin heat in winter. It's nice and smooth. The tach reads high compared to what you're used to seeing -- takes a couple of flights to get used to that. I cruise between 5000 and 5300 RPM usually. That means a prop speed of roughly 2000 - 2200 RPM.

TBO is 2,000 hours, and I get the sense it will make it there with no problem. Unlike a Conti or Lycoming, my understanding is that during a major overhaul the crankshaft will get replaced, but not the cylinders. I don't know, with 450 hours on the engine I doubt I'll need to worry about it.

There are tens of thousands of Rotax engines flying, and they have been in the field for decades. This is not new and exotic technology. Rotax has been very, very attentive to the engines, with tons of freely available documentation (light and heavy repair manuals, service instructions, etc). and changes over the years to improve reliability and longevity.

There is a guy at my field that tore down a 912 at TBO and said there was absolutely no need to overhaul it. They are here to stay for sure, just wish they could find a way to lower the prices.
 
I have about 750 hours behind the 912 ULS and about 350 behind the 914 turbo. I have 80 hours behind the Continental O-200D. To me, there’s no comparison between the Continental and 912/914. No offense to those who like the O-200D, it’s a fine engine and reliable indeed, but after difficulty starting with 15 degree temperatures and carb ice on more than one occasion it’s hard to go back to it after you’re exposed to Rotax.

The 914 turbo is my favorite GA piston aircraft engine. 100 HP to 16,000ft, smooth as a top, starts and stops with such ease it’s baffling no matter the temperature. I would probably do a 914 turbo if you’re going to be operating in higher density altitudes around 5,000ft+ and a 912 ULS otherwise. If you want the ultimate performer, 915 iS with the MT constant speed no question.

If Honda were to build an engine, I think it would look almost identical to these 900 series engines. They’re little marvels!
 
I've flown a couple foxes and I would go with the Rotax. If you can't afford the fuel injected or turbo version, you can always upgrade down the line. 914 is an awesome option. The extra weight of the O200 on the nose actually makes a big of difference, although the S7 SS has larger elevators that should make up for that, but the wing sweep will be a little different. The Kitfox has been refined for the rotax, unless you have a good reason otherwise, it's the best option IMO.
 
The main downside is the scarcity of certified Rotax mechanics. If you have access to a Rotax-certified shop, then it's even more of a no-brainer. Also, you can take Rotax maintenance classes that will allow you to perform maintenance and inspections yourself.
On my E-AB, i just fix it myself. Most stuff is no big deal and you can get everything except the overhaul manual online. Ain't nothing that special about a Rotax (parts aren't cheap, but neither are parts from Continental). My A&P does the condition inspection. No permission from Rotax required, near as I can tell.
If I ever have to do a major overhaul, I guess I could take the class to get access to the manual.
 
The main downside is the scarcity of certified Rotax mechanics.
No permission from Rotax required, near as I can tell.
It is my understanding, that the "certified Rotax mechanic" only applies to LSA aircraft certified under a Consensus Standard which determines who can work on the engine. It's not applicable to an E/AB aircraft with a Rotax installed. However, there is a warranty requirement for certain work performed.

Even Rotax powered aircraft that fall under Part 43 do not require Rotax certification to work on (except warranty items) and must only comply with the experience/performance requirements of Part 65 and 43.
 
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Yes, you guys are correct. What I should've written is that the Rotax classes teach you "how" to perform maintenance, not "allows." The point is that the classes are worthwhile to you as the owner, as is another trained set of eyes if there's a Rotax-certified A&P within reach. There are operational and maintenance peculiarities to the Rotax that don't apply to the Lycs and Contis that are important to learn.
 
My internal bias is airplane engines over autos.... the Rotax is an airplane engine though and I don’t like continentals (another personal bias). I would go with the Rotax....
 
There is a guy at my field that tore down a 912 at TBO and said there was absolutely no need to overhaul it.
That is dependent on how well the engine has been taken care of. For instance, changing oil and filter at recommended Rotax intervals and keeping vibrations to a minimum (carbs sync’t). Be kind to that gearbox!
 
That is dependent on how well the engine has been taken care of. For instance, changing oil and filter at recommended Rotax intervals and keeping vibrations to a minimum (carbs sync’t). Be kind to that gearbox!
That was one of the things that impressed me, on my latest go-around at looking at engine-failure causes for homebuilt aircraft. Here's a summary:
engine_causes.jpg

Again, the majority of "Non-Certified Four Strokes" are Rotax 912s and 914s. Notice there *were* no homebuilt accidents (1998-2017) attributed to failure of the gear box.

I keep sketching a Fly Baby with a 912. But then, ADS-B is cheaper....

Ron Wanttaja
 
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