110 hp 4 cyl from Taiwan

[facthunter]

  What really matters is specific fuel consumption. Hp/ litre of fuel, weight  reliability and cost. The capacity of the motor is irrelevant but big bores can have more wear before they are in need of work to be done. WHO  wants to listen to a motor screaming it's head off on a motorbike OR in a small plane? Nev

[RFguy]

Some segments will want a high hp/lbs ratio -  certainly in the LSA, that's prime. IE where the engine is an appreciable percentage of the  AUW .  And that's a place for the geared engine. Rotax has been successfull, because mostly, they are very reliable.  I am surprised of any manufacturers targeting the low end  / LSA market being not geared.  Except for reaplcements- since airframes are usually built around some nose weight.

 

 

[facthunter]

Gears are a WEIGHT penalty,  costly and complex  and absorb power. You can't successfully gear an engine to a flywheel which the prop inevitably is. When a motor has enough torque you absolutely don't need the gearbox for our sized planes.  Nev

[Old Koreelah]

All my researching of engines led me to direct drive. I was keen on Suzuki’s bulletproof G10 triple, but a gearbox made it too heavy. A good multiple belt drive should be okey- after all, lots of helicopters depend on belts.

[skippydiesel]

16 hours ago, Thruster88 said:

Pilots don't care about hp per litre, they just want an engine that works. One reason Lycoming and Continental have not been dethroned in their segment. 

 

Brake specific fuel consumption only cares a little about hp per litre 

Brake-specific fuel consumption - Wikipedia

EN.WIKIPEDIA.ORG

 

Speak for yourself🙃

 

I'm a post WW2 Euro baby = thrift in almost all I do.

 

The reason LYCon still sit on the throne, is because they are  made by Uncle Sam, who has the largest & most partisan market, on his doorstep.

 

Any aviation  product, developed / made outside the US, has almost insurmountable difficulties in breaking into that market ,which just happens to be the largest single markets of its kind. This also means that products from within, pretty much dominate the rest of the aviation World. One of the consequences, is the persistence of "traditional" (I'm trying to be nice) products way past their use by date.

 

[facthunter]

 UL and Rotax aren't impeded in getting into the US market. Upgrades in metallurgy improve the "past their use by date" as you disparagingly dismiss anything aircooled and not covered in Pipes and hoses. Aircraft engines are a very small part of Rotax's activity and they are getting MORE costly, so a cheaper simpler alternative is welcome in my mind where one has choices to decide from, to be a welcome option.  It also has the carburettor is a safe place. Nev

Edited September 8, 2023 by facthunter

[skippydiesel]

Cant agree Nev - I hesitate to say my opinion is fact but history tells us the US is a very difficult market to crack (not just for aviation).

 

That Rotax are "in" at all is likely to do with shear persistence/Canadian association and possibly the use of their engines in military drones and skidoos etc and the grudging realisation that for aircraft in the sub 700kg TO range there is probably nothing better ("better" covering a range of posative attributes).

 

Of course Rotax is slowly working its way up the aircraft size/weight range, could there be a 200hp in the works?

 

I would also question quite how much Rotax aircrafts are "in" - some of the US Forums have a distinctly anti Rotax "flavour".

 

As for air cooled direct drive - nothing wrong with it, if you don't mind the inbuilt inefficiencies eg need for fuel cooling, big bore/low rpm engines, relativly high noise, vibration & fuel consumption/hp.

 

I learnt to fly behind an air-cooled engine - its was great! I just happen to feel that but for the US market holding back development, better options would likely have arrived before now.

 

Asides from an unhealth relationship with guns, the Americans seem obsessed with large bore engines - to me this is a cultural, not rational, position.

[facthunter]

Just get the facts and go fly. All these conspiracies are just inventions of the mind  . Do proper research. Not all aircooled engines are that good either but they don't have the complexity of liquid cooling, just to cool the heads to a lower than efficient figure.   Where's this need for fuel cooling?.  It's a problem with Rotax if you have to divert some back to the tank. Nev

[facthunter]

I put a comment earlier about the later Rotax crankshafts as to how they are now built stronger but must be replaced if the runout exceeds a small figure. Straight from Rotax itself and obviously necessary. I would have been surprised if they Hadn't but NO ONE responds at all. I want Rotax to be in the game but proper discussion is based on FACTs. Not it must be perfect because ROtax is on the Packet. I read a lot of US stuff It's about the only place you get where you get a 1/2 intelligent discussion of matters aviation. and where most of it is still happening although it's diminishing everywhere.  ROtax get a fair run as far as I see it.  It's seen as the future by many, there. Nev

Edited September 8, 2023 by facthunter

[BrendAn]

4 hours ago, facthunter said:

Gears are a WEIGHT penalty,  costly and complex  and absorb power. You can't successfully gear an engine to a flywheel which the prop inevitably is. When a motor has enough torque you absolutely don't need the gearbox for our sized planes.  Nev

How do thousands of rotax engines and gearboxes perform good and last a long time . According to you they can't do that.

[danny_galaga]

I like all sorts of engines, hence my original post. What I like about this engine is that it will sound like a 'big boy' engine, but not at a big boy price. 

 

I like Rotax for the most part, but some homebuilts would just sound that much better at 2500 rpm, especially replicas 🙂

[BrendAn]

A 912 uls is the same weight and HP as an 0200 . Installed minus cowling.

[BrendAn]

1 minute ago, danny_galaga said:

I like all sorts of engines, hence my original post. What I like about this engine is that it will sound like a 'big boy' engine, but not at a big boy price. 

 

I like Rotax for the most part, but some homebuilts would just sound that much better at 2500 rpm, especially replicas 🙂

I just watched a YouTube about a Yamaha phaser powered kitfox. They seem to be a good option for ultralights. Definately not low revving though.

[Blueadventures]

I am not about knocking engines and I read there are some 912 ULS engines needing gearbox overhaul at less than 600 hours and not Avgas related.  I’m presently putting together a tool box for dismantling the 912 gearbox so I am ready for any such work.  Not saying all just some suffer this for some reason; and can be the luck of the draw, a Friday or Monday assembled g/b or the oil used etc. cheers

Edited September 8, 2023 by Blueadventures

[facthunter]

it's easy to just label ME a Rotax knocker. If you examine what I actually say it's just an analysis. point out the errors if you wish but don't just write me off because I do plenty of research and do have some considerable  experience. and converse with many others who supplement it.. The Rotax gearbox is a very complex jigger and would also weigh quite a bit and would add a lot to the cost.  Nev

[skippydiesel]

1 hour ago, Blueadventures said:

I am not about knocking engines and I read there are some 912 ULS engines needing gearbox overhaul at less than 600 hours and not Avgas related.  I’m presently putting together a tool box for dismantling the 912 gearbox so I am ready for any such work.  Not saying all just some suffer this for some reason; and can be the luck of the draw, a Friday or Monday assembled g/b or the oil used etc. cheers

No offence Blue but I realy dislike unsubstantiated statements like this.  Reason; they and possibly the reports you have read/heard, are without context (history - service, usage, prop type,  number of similar failures, as a percentage of total in use, etc). All mechanical "things" (technical term for man made object with moving parts) are subject to wear and failure that may be accelerated by poor usage. These days. most will have some sort of in service life expectancy, either through testing or experience - I have not heard of Rotax 9 gear box or engine general failures at 600 hrs or anywhere near this operational time. From geriatric memory - Rotax recommend that the gearbox be inspected (may require servicing) at 600 hrs for engines run on AvGas and  1200 hrs for those run on ULP (reasons are common knowledge)

 

28 minutes ago, facthunter said:

it's easy to just label ME a Rotax knocker. If you examine what I actually say it's just an analysis. point out the errors if you wish but don't just write me off because I do plenty of research and do have some considerable  experience. and converse with many others who supplement it.. The Rotax gearbox is a very complex jigger and would also weigh quite a bit and would add a lot to the cost.  Nev

 

Nev  You comments are without doubt based on his extensive experience & training - fair enough however your  "tone" (subjective attribute, conferred by reader/me) does seem to be biased against Rotax 9's, in that some of his technical observations (while accurate) do not appear to negatively effect the service life of these engines. To me there can only be two possible reasons:

• Rotax are good at promoting their engine & hiding its defects ie most of us believe they are one of the few aircraft engines (in their class) that generally make it (pass) TBO without major "surgical" intervention - this may be marketing hype & not be true.
• Rotax engines somehow transcends the conventional engineering wisdom of the past (at least in some respects) -if this is correct, it would mean that you might have to re-examine your training/knowledge.

[BrendAn]

45 minutes ago, facthunter said:

it's easy to just label ME a Rotax knocker. If you examine what I actually say it's just an analysis. point out the errors if you wish but don't just write me off because I do plenty of research and do have some considerable  experience. and converse with many others who supplement it.. The Rotax gearbox is a very complex jigger and would also weigh quite a bit and would add a lot to the cost.  Nev

I am not writing you off but you are always telling us how bad rotax engines are when that is not the case at all. The 912 gearbox is part of the engine package and still comes in at the same weight as an 0200.  And they are a very simple gearbox.

[facthunter]

The fact they beefed up the crankcase and crankshaft  is consistent with my comments and proves I have some idea, doesn't it.?  There's nothing MAGIC about Rotax  engineering, or anyone else's for that matter.. Nev

[facthunter]

I tell you aspects I don't like about their layout  and complexity of the cooling and oil plumbing. price and.price of parts etc. Look at all the posts here about all that stuff. IF you can do without you are better off.. Is that NOT so? .   Have I ever lied or failed to elaborate? NO. I wouldn't want to see ROtax go out of business but not everyone can afford one or wants what it is.  Nev

[danny_galaga]

I like lamp.

[Blueadventures]

1 hour ago, skippydiesel said:

No offence Blue but I realy dislike unsubstantiated statements like this.  Reason; they and possibly the reports you have read/heard, are without context (history - service, usage, prop type,  number of similar failures, as a percentage of total in use, etc). All mechanical "things" (technical term for man made object with moving parts) are subject to wear and failure that may be accelerated by poor usage. These days. most will have some sort of in service life expectancy, either through testing or experience - I have not heard of Rotax 9 gear box or engine general failures at 600 hrs or anywhere near this operational time. From geriatric memory - Rotax recommend that the gearbox be inspected (may require servicing) at 600 hrs for engines run on AvGas and  1200 hrs for those run on ULP (reasons are common knowledge)

 

 

Nev  You comments are without doubt based on his extensive experience & training - fair enough however your  "tone" (subjective attribute, conferred by reader/me) does seem to be biased against Rotax 9's, in that some of his technical observations (while accurate) do not appear to negatively effect the service life of these engines. To me there can only be two possible reasons:

• Rotax are good at promoting their engine & hiding its defects ie most of us believe they are one of the few aircraft engines (in their class) that generally make it (pass) TBO without major "surgical" intervention - this may be marketing hype & not be true.
• Rotax engines somehow transcends the conventional engineering wisdom of the past (at least in some respects) -if this is correct, it would mean that you might have to re-examine your training/knowledge.

Skip you read too deep into things and your comment is kinda like mine as your unsubstantiated comment that the 912 g/b will definitely last 600 plus hours.  I was just saying I’m readying myself for when I need to do an inspection.  Like I have the pullers to change a sprag  clutch when the time comes.  Being a maintainer of machinery I build on my tool inventory as my background called on being self sufficient as much as possible.  There have been the failures as I mentioned in my post, in the real world; so you may need to look in different areas to gain the information.  

[skippydiesel]

58 minutes ago, Blueadventures said:

Skip you read too deep into things and your comment is kinda like mine as your unsubstantiated comment that the 912 g/b will definitely last 600 plus hours.  I was just saying I’m readying myself for when I need to do an inspection.  Like I have the pullers to change a sprag  clutch when the time comes.  Being a maintainer of machinery I build on my tool inventory as my background called on being self sufficient as much as possible.  There have been the failures as I mentioned in my post, in the real world; so you may need to look in different areas to gain the information.  

".........your unsubstantiated comment that the 912 g/b will definitely last 600 plus hours"  I don't recall saying/writing this.

 

FYI - The Sprag Clutch (SC) can be replaced without removing the gear box. I have replaced one, don't recall any special tools but the aforementioned dodgy memory, may be in play. The SC was one of the Rotax weak points being particularly susceptible to the forces generated by the earlier engine start system (now mitigated by the Soft Start ignition) and the failure of some pilots to replace a weak start battery, as soon as identified as such.

[skippydiesel]

2 hours ago, facthunter said:

The fact they beefed up the crankcase and crankshaft  is consistent with my comments and proves I have some idea, doesn't it.?  There's nothing MAGIC about Rotax  engineering, or anyone else's for that matter.. Nev

You are correct however this changes little, as most if not all mechanical systems undergo an evolutionary/improvement process during their production life.

2 hours ago, facthunter said:

I tell you aspects I don't like about their layout  and complexity of the cooling and oil plumbing. price and.price of parts etc. Look at all the posts here about all that stuff. IF you can do without you are better off.. Is that NOT so? .   Have I ever lied or failed to elaborate? NO. I wouldn't want to see ROtax go out of business but not everyone can afford one or wants what it is.  Nev

We know that you deep and abiding reservations about Rotax engines technical fitness.

 

"their layout" - I assume you are referring to your frequent observations on twine carb, carb above, induction, high rpm/gearbox ?

"cooling"  - just the heads?  - would you like them better if the barrel was included? OR is it liquid cooled aero engines in general?

"oil plumbing" - I agree, not conventional but works, why the beef?

"price  of parts" - I haven't looked at the price of the equivalent Ly/Con parts of late, they used to be significantly more expensive, than Rotax. You may be comparing with Jab, this I give you without hesitation but then look at the reputation. Unless we have all been completely brain washed by Rotax (?) & the negative press on Jab it would seem that most Jabs (& Ly/Cons) will require "major surgery" well before TBO, while Rotax will not  - in my mind this likely balances the cost  equation. One one further point - service items - shop around (as I do) - parts not so expensive after all. This is not the case for those  who do not make the effort  or to lack the confidence to do so, then OM IS expensive as are most aircraft parts.

"lied or failed to elaborate" - Of course not but you don't need to - as I said your tone would seem to be fairly consistently negative/disparaging towards the Rotax offerings.

"not everyone can afford one" - True, but then there are not to many aspects of powered flight, in the 80hp and above,  that can be considered cheap. While I may wish that there were no financial hurdles, to all who may aspire to own/fly a small (or large) aircraft, that's not the way the World seem to work - I cant afford a private jet (not sure that I aspire to own one, cant be much fun to fly).

 

 I support your KISS principals Nev but also recognise that efficiencies may also come from some compromise in this philosophy - I am sure I have heard/read somewhere that this is one of the ways technology advances - simplicity, followed by complexity, before refinement back to simplicity.

[Blueadventures]

40 minutes ago, skippydiesel said:

".........your unsubstantiated comment that the 912 g/b will definitely last 600 plus hours"  I don't recall saying/writing this.

 

FYI - The Sprag Clutch (SC) can be replaced without removing the gear box. I have replaced one, don't recall any special tools but the aforementioned dodgy memory, may be in play. The SC was one of the Rotax weak points being particularly susceptible to the forces generated by the earlier engine start system (now mitigated by the Soft Start ignition) and the failure of some pilots to replace a weak start battery, as soon as identified as such.

Skip if you reread my post I have not said I need to remove the gear box to maintain the sprag clutch.  I was referring to building on my tool inventory . At the moment it includes tools for example flywheel pullers (long and short) for use to access the sprag clutch. What puller type did you use to access the sprag clutch you maintained?

[facthunter]

It wouldn't matter what I say would it? NO evaluation or criticism will be accepted of any odd thing about the ROtax. MY "TONE" ??? You are hypersensitive. You wouldn't know ME from a bar of soap.. Nev