I am in the process of evaluating the potential for use of the BMW R1150 motorcycle engine for my future RV-12 build(s). There is a link I've located, http://www.microlightsport.co.uk/Catalogue/New/bmwengine.htm, that provides some basic information for this 100HP coupled with a "Takeoff" drive unit and the overall information for weight and packaging envelope look similiar to the Rotax 912 ULS at around 60% of the cost. I'm having a slight problem linking to the "contact us" site but will send them a request "snail mail" for more information and update as received on this site.
Van's Air Force
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BMW R1150 Series Engine
- Thread starter rv9flyer
- Start date
ddurakovich
Well Known Member
The guys up near Toronto (Ultralightnews.com) are showing the 912 ULS for about $3000 USD more than the BMW. While 3 grand is a chunk to be sure, I wonder when you add the ocean freight costs, new engine mount, potential cowling changes etc. if that is really cost effective?
I think BMW engineering is as good as it gets, but I suspect the reduction drive unit is homegrown, and therefore a lesser known commodity. Combine that with the absolute lack of support you will get from Van's and.......
My $0.02!
I think BMW engineering is as good as it gets, but I suspect the reduction drive unit is homegrown, and therefore a lesser known commodity. Combine that with the absolute lack of support you will get from Van's and.......
My $0.02!
RudiGreyling
Well Known Member
Hi Guys,
I fly microlights, and the search is always on for a cheaper alternative to the Rotax, Just as the search is on for a cheaper Lycoming alternative.
That being said, we had a guy here that fitted a BMW twin to his microlight, did a seeming good job, lots of engeneering and scratching his head to make it work, but after 3 engine outs he gave up and fitted a Rotax.
In this engine category there are a lot of recreational engines that seamingly will do the job, from motorbikes to jet-ski's etc etc. There is also a lot of new manufactures that try their hand in this area.
Yes if you fit a Rotax you fit a more expensive motor, but it is well understood, and expertise is everwhere available, and it has stood the test of aviation over a bit of time.
The Jabiru motor seems to making inroads as well, it is an aviation motor, and being produced specifically for aviation, they had their troubles, but they are being sorted out.
It is all about piece of mind. With a Rotax you are going to fly with a little more confidence.
My 2c.
Kind Regards
Rudi
I fly microlights, and the search is always on for a cheaper alternative to the Rotax, Just as the search is on for a cheaper Lycoming alternative.
That being said, we had a guy here that fitted a BMW twin to his microlight, did a seeming good job, lots of engeneering and scratching his head to make it work, but after 3 engine outs he gave up and fitted a Rotax.
In this engine category there are a lot of recreational engines that seamingly will do the job, from motorbikes to jet-ski's etc etc. There is also a lot of new manufactures that try their hand in this area.
Yes if you fit a Rotax you fit a more expensive motor, but it is well understood, and expertise is everwhere available, and it has stood the test of aviation over a bit of time.
The Jabiru motor seems to making inroads as well, it is an aviation motor, and being produced specifically for aviation, they had their troubles, but they are being sorted out.
It is all about piece of mind. With a Rotax you are going to fly with a little more confidence.
My 2c.
Kind Regards
Rudi
BMW Engine Application
I amazed that the responses to the initial information on the BMW motorcycle engine application for the RV-12 parallels, almost exactly, what the Subaru/Lycoming discussions were back in 2001 when I was building my RV-9A. I very much appreciate everybodys "2 cents worth" and, as anyone who is/has built an aircraft has found, the cumulative total is a bunch of money. I spent about 5 years riding a BMW R75/5 and would not classify that combination as "rough". Now maybe the newer R1200 is different but I still believe it has two cylinders that fire at equal events of 360 degrees.
I would really like to understand the failure modes that the one fellow experienced, in fact I believe it's essential for anyone considering this engine option to fully understand any history. Could the writer try to find out the "root cause" verified for each incident. I know when I was looking at the Subaru, there were two "engine outs" one caused by a turbocharger seal and the other caused by not disabling the "vehicle speed" calculation by RPM limit.
MSA information indicates that they now have 64 aircraft with 3 years of trouble free flying with this combination. The drive unit is manufactured in Germany by Takeoff GmbH.
As far as cost, the information I have the base R1200 engine is 6250 (Euro$) and the whole package, including gear reduction unit, exhaust system, and all accesories totals around $9,000 USD. The information I have on the Rotax is more like $15350. The total weights of the two engines are very close and based on initial information, the BMW may be 158mm (6.22") wider.
I believe that Van's will design and equip the prototype with a Rotax, which I am in no way faulting, but my hopes is that the cowling can be designed to anticipate potential use of the BMW R-1200 engine.
Keep the posts coming, this is all good! Remember, the main emphasis of the EAA was founded to be a learning experience and, as anyone who has built and flying, it's a good one.
I amazed that the responses to the initial information on the BMW motorcycle engine application for the RV-12 parallels, almost exactly, what the Subaru/Lycoming discussions were back in 2001 when I was building my RV-9A. I very much appreciate everybodys "2 cents worth" and, as anyone who is/has built an aircraft has found, the cumulative total is a bunch of money. I spent about 5 years riding a BMW R75/5 and would not classify that combination as "rough". Now maybe the newer R1200 is different but I still believe it has two cylinders that fire at equal events of 360 degrees.
I would really like to understand the failure modes that the one fellow experienced, in fact I believe it's essential for anyone considering this engine option to fully understand any history. Could the writer try to find out the "root cause" verified for each incident. I know when I was looking at the Subaru, there were two "engine outs" one caused by a turbocharger seal and the other caused by not disabling the "vehicle speed" calculation by RPM limit.
MSA information indicates that they now have 64 aircraft with 3 years of trouble free flying with this combination. The drive unit is manufactured in Germany by Takeoff GmbH.
As far as cost, the information I have the base R1200 engine is 6250 (Euro$) and the whole package, including gear reduction unit, exhaust system, and all accesories totals around $9,000 USD. The information I have on the Rotax is more like $15350. The total weights of the two engines are very close and based on initial information, the BMW may be 158mm (6.22") wider.
I believe that Van's will design and equip the prototype with a Rotax, which I am in no way faulting, but my hopes is that the cowling can be designed to anticipate potential use of the BMW R-1200 engine.
Keep the posts coming, this is all good! Remember, the main emphasis of the EAA was founded to be a learning experience and, as anyone who has built and flying, it's a good one.
Dave_Boxall
Well Known Member
Smart Mercedes Engine
Anybody looking for an alternaitive to the Rotax should take a look at this. It's an aviation version of the Mercedes Smart Car 3-cylinder engine.
http://www.ecofly.de/english.htm
Available in the basic 82 hp version, the 100 hp turbo (smart roadster) and 60 hp diesel.
Dave
Anybody looking for an alternaitive to the Rotax should take a look at this. It's an aviation version of the Mercedes Smart Car 3-cylinder engine.
http://www.ecofly.de/english.htm
Available in the basic 82 hp version, the 100 hp turbo (smart roadster) and 60 hp diesel.
Dave
Alternative engines
There is a big difference between one guy fitting an engine into his aircraft and a tested configuration that has over 60 flying.
One thing I would recommend is that you make sure you are not the first RV-12 with this engine, unless you want to send *a lot* of time fiddling and tinkering. Engine mount, exhaust system, fuel plumbing, cowls, and probably a lot of other stuff will need to be modified.
If you're up to this challenge, then I'm sure it will be great fun and very rewarding. You seem to have indicated that you will build several RV-12s. If that is the case, then it may be worth the extra effort to get this engine working.
I'm all for innovation and progress. Without guys like you, we'd still be living in caves, and dragging our wives by their hair. Please keep us posted!
There is a big difference between one guy fitting an engine into his aircraft and a tested configuration that has over 60 flying.
One thing I would recommend is that you make sure you are not the first RV-12 with this engine, unless you want to send *a lot* of time fiddling and tinkering. Engine mount, exhaust system, fuel plumbing, cowls, and probably a lot of other stuff will need to be modified.
If you're up to this challenge, then I'm sure it will be great fun and very rewarding. You seem to have indicated that you will build several RV-12s. If that is the case, then it may be worth the extra effort to get this engine working.
I'm all for innovation and progress. Without guys like you, we'd still be living in caves, and dragging our wives by their hair. Please keep us posted!
N941WR
Legacy Member
I'm not so sure this will be the case. Based on Van's past stance regarding alternet engines and the very tight limits (speed, weight, etc.) placed on Light Sport Aircraft (LSA) I think the man and the company will be even more adiment about using only the recommended engine.rv9flyer said:
Truth is, I don't have a clue but that's what I'm guessing. Give them a call; you might be able to change the course of history in your favor.
swisseagle
Well Known Member
BMW replaced by Rotax!
Hello All!
A friend of mine had installed an BMW in his Breezer Breezer Homepage, but in german language
In the beginning, he could not get out the 100hp power as advertised, so he had to design his own much bigger airfilter, this helped, also he had to make up to 4 exhaust systems untill he get enough power.
In the end, he had 100hp, but then the gearbox coud not handle the pulses from the engine and gets broken a few times!! Also the electrical CS Prop. did not like the pulses and also get broken (gears for adjusting the pitch).
He was tired to fly around like this ... and replaced the engine with an Rotax 100hp. Best of it all, he gain aprox. 30lb usefull weight! The downside is, he must do all the testflight again, this are up to 30h if you do it correctly.
Dominik
Switzerland
Hello All!
A friend of mine had installed an BMW in his Breezer Breezer Homepage, but in german language
In the beginning, he could not get out the 100hp power as advertised, so he had to design his own much bigger airfilter, this helped, also he had to make up to 4 exhaust systems untill he get enough power.
In the end, he had 100hp, but then the gearbox coud not handle the pulses from the engine and gets broken a few times!! Also the electrical CS Prop. did not like the pulses and also get broken (gears for adjusting the pitch).
He was tired to fly around like this ... and replaced the engine with an Rotax 100hp. Best of it all, he gain aprox. 30lb usefull weight! The downside is, he must do all the testflight again, this are up to 30h if you do it correctly.
Dominik
Switzerland
BMW in Breezer
I think we might be comparing apples to oranges here. I don't understand what the full configuration was that your friend was installing. First off, what method was he using to determing actual horsepower output from the engine? Which gearbox did he break "a few times"? What was he using for a CS prop?
The package I'm trying to evaluate is an R1200 engine with a Takeoff drive unit that comes with all accessories, including exhaust system and weighs over 2Kg LESS than the Rotax. The US LSA rules do not allow for a CS prop so that part would not apply.
I think we might be comparing apples to oranges here. I don't understand what the full configuration was that your friend was installing. First off, what method was he using to determing actual horsepower output from the engine? Which gearbox did he break "a few times"? What was he using for a CS prop?
The package I'm trying to evaluate is an R1200 engine with a Takeoff drive unit that comes with all accessories, including exhaust system and weighs over 2Kg LESS than the Rotax. The US LSA rules do not allow for a CS prop so that part would not apply.
N941WR said:
I believe that Van's traditionally builds the prototype/proof of concept aircraft with a very "conserative/mainstream" engine. In the 9 you're building, that was an O-320 with subsequent builds O-235, etc. If you look at the 10, the first engine was a Lycoming O-540 and then a Continental. You're correct in the performance specs. being fixed for the LSA but I would believe that if you had two engine packages with essentially the same power output weighing within 2Kg of eachother that would be a viable package.
I am in communication with Van's regarding this but, to date, it has just consisted of me sending email updates.
swisseagle
Well Known Member
The motor and the gearbox where from Takeoff, its a BMW 1150 cm3 100PS, the Propeeller is an Woodcomp SR2000, electric Constant-Speed with an diameter of 1.7m
They made comparison groundtests and calculate the outputpower, with each exhaust system they gain RPM.
The weight is mesured in appels and appels, ready to fly with BMW and ready to fly with Rotax
I do not want to speek the BMW motor down, it is a very good motor, he only burn about 14l of Mogas and was really reliable, but the conversion to an airborn motor is not finished and they still work on it. But the RV-12 is also under work and it will take some time.
here is an page in english http://www.spang-air.de/index.html from an german, he build his Cherry in the US and has moved now back to germany. He describe a lot about the things around the motor build in process.
Dominik
They made comparison groundtests and calculate the outputpower, with each exhaust system they gain RPM.
The weight is mesured in appels and appels, ready to fly with BMW and ready to fly with Rotax
I do not want to speek the BMW motor down, it is a very good motor, he only burn about 14l of Mogas and was really reliable, but the conversion to an airborn motor is not finished and they still work on it. But the RV-12 is also under work and it will take some time.
here is an page in english http://www.spang-air.de/index.html from an german, he build his Cherry in the US and has moved now back to germany. He describe a lot about the things around the motor build in process.
Dominik
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N941WR
Legacy Member
rv9flyer said:
I hope you are right as I do believe that alternate engines improve the breed. From the experience I have gained putting an O-290 in my -9, Van's really doesn't support anything but the O-320 for this aircraft. They are depending on me to tell them such things as what exhaust system I need, throttle cable, etc. This experience just makes me wonder what they are going to say when you tell them you are putting a motorcycle engine in an RV-12.
BTW, more than one person at Van's has tried to talk me into building a -9A. It is almost as if the -9 is the red headed stepchild. This doesn't even mention the comments I have heard from them when I tell them which engine I'm going to use.
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RudiGreyling
Well Known Member
Hi RV9flyer,
For some people is all about the money, the other about the challenge and satisfaction of success of making something different work, for others it is about piece of mind, tried and tested by many.
This is one of those never ending debates, but please keep us posted on your findings.
Kind Regards
Rudi
[font="]PS: I followed the link you provided and see they advertise it with "[/font]CENTRIFUGAL CLUTCH"[font="]. This reminded me of one of his gripes while flying the BMW it was that one have to anticipate the clutch kicking in or not. Especially during tricky landings when one is required to play with the power setting, and during simulated engine outs. This creates and additional workload during tricky landings and something to keep in the foremost of you mind. I do not know if your option would include this or not.[/font]
Ditto...you get the pioneers and you get the conservatism, I'm the latter.rv9flyer said:
Sorry but I do not have much info on the exact causes, the last time I saw the guy and his plane I asked him what happened to the BMW since it was not fitted anymore, His response short and sweet: "After 3 engine outs I decided to go Rotax". He was annoyed with his failure and not really interested to talk about it.rv9flyer said:
My main aim was to tell you that if you go with intended you go with a minimalistic knowledge base where as with a Rotax it is much better understood in general.rv9flyer said:
For some people is all about the money, the other about the challenge and satisfaction of success of making something different work, for others it is about piece of mind, tried and tested by many.
This is one of those never ending debates, but please keep us posted on your findings.
Kind Regards
Rudi
[font="]PS: I followed the link you provided and see they advertise it with "[/font]CENTRIFUGAL CLUTCH"[font="]. This reminded me of one of his gripes while flying the BMW it was that one have to anticipate the clutch kicking in or not. Especially during tricky landings when one is required to play with the power setting, and during simulated engine outs. This creates and additional workload during tricky landings and something to keep in the foremost of you mind. I do not know if your option would include this or not.[/font]
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Double Dittos Rudy
Double Dittos Rudy, I did wind up going with an O-320 E2D in my 9A and even kept it at 150 HP so I would fall into the conservative realm also. My thinking process was, and still is, what would you put your wife or child in and fly cross country at night? That being said, I am of the belief that we should always be "pushing the envelope" where there's time and resources to allow a good decision base. If Van's was looking at a 65 HP Continental engine it would be different. I don't see the Rotax falling into that catagory, at least for me, which is why I'm looking further.
The person I've been dialoging with, Deepak Mahajan of Micro Light Sport Co., has indicated that the centrifugal clutch will engage above approximately 2100 RPM so the pilot must factor in the loss of "residual thrust" when throttling back for landing.
Ron Drake
"Make it Happen"
Double Dittos Rudy, I did wind up going with an O-320 E2D in my 9A and even kept it at 150 HP so I would fall into the conservative realm also. My thinking process was, and still is, what would you put your wife or child in and fly cross country at night? That being said, I am of the belief that we should always be "pushing the envelope" where there's time and resources to allow a good decision base. If Van's was looking at a 65 HP Continental engine it would be different. I don't see the Rotax falling into that catagory, at least for me, which is why I'm looking further.
The person I've been dialoging with, Deepak Mahajan of Micro Light Sport Co., has indicated that the centrifugal clutch will engage above approximately 2100 RPM so the pilot must factor in the loss of "residual thrust" when throttling back for landing.
Ron Drake
"Make it Happen"
greylingr said:
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