PPRuNe Forums

Go Back   PPRuNe Forums > Non-Airline Forums > Private Flying
Forgotten your Username/Password?

Private Flying LAA/BMAA/BGA/BPA The sheer pleasure of flight.


Reply
 
Thread Tools
Old 6th Apr 2011, 15:47   #1 (permalink)
 
Join Date: Aug 2010
Location: Ecuador
Age: 36
Posts: 227
Upgrading Rotax 912UL (80HP) to Rotax 914UL (115HP), experience anyone?

Dear all,

I am a Rotax 912UL owner, (80HP) currently upgrading to a bigger aircraft, and therefore I have the 912ULS with 100 horses version in mind.

However, I will have to sell my 80HP Rotax to be able to invest the money into my new machine……….and selling it proves to be rather hard to do!

So somebody called my attention to this site:

Bully Hawk Aero Performance, Rotax Performance and Upgrade Kits

It is about upgrading from 912UL to 914UL, in other words from 80HP to 115HP.

Naturally, they talk about it like it´s the 8th miracle of the world, but I call upon you, experienced aviators; those who know all the tricks in the book and more: "is this really as good as it sounds, considering maintenance costs, reliability, performance & TBO figures"?

For your reference, my Rotax has about a 1000 hours on.


Best regards,


###Ultra Long Hauler###
Ultra long hauler is offline   Reply
Old 7th Apr 2011, 20:11   #2 (permalink)
 
Join Date: Aug 2010
Location: Ecuador
Age: 36
Posts: 227
Mmmm, zero reactions……………….


That kind of answers my questions…………….nobody with any experience with this issue!!

Smells like a No No…………


###Ultra Long Hauler###
Ultra long hauler is offline   Reply
Old 7th Apr 2011, 22:49   #3 (permalink)
 
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,406
You might want to try the LAA. There's a lot of folks there with Rotax experience.

Also, I seem to recall that Skydrive is the UK dealer with a lot of experience in maintaining Rotax engines.
BackPacker is offline   Reply
Old 8th Apr 2011, 06:05   #4 (permalink)
 
Join Date: Jul 2010
Location: EBZH
Posts: 1,333
I can't help wondering what kind of money you can still hope to get from your current 912 with a thousand hours on it. Isn't its full life span limited to 1500 hours?
Sorry to push back on your nice plans...
Jan Olieslagers is offline   Reply
Old 8th Apr 2011, 07:12   #5 (permalink)
 
Join Date: Aug 2007
Location: Plumpton Green
Age: 70
Posts: 737
Recent Rotaxes 912s have a TBO (time between overhaul) of 1500 hours, not a life span of 1500 hours.

I don't think anybody in this country would spend $8500 to upgrade an old Rotax 912 in order to sell it.
patowalker is offline   Reply
Old 8th Apr 2011, 07:14   #6 (permalink)
 
Join Date: Sep 2009
Location: N.YORKSHIRE
Posts: 432
Try here.
Light Aircraft Association :: View Forum - Aircraft Construction & Maintenance
Flyingmac is offline   Reply
Old 8th Apr 2011, 07:34   #7 (permalink)
 
Join Date: Apr 2003
Location: Midlands
Posts: 2,249
“Recent Rotaxes 912s have a TBO (time between overhaul) of 1500 hours”

Nope, it is 2000 hours (TBO) with many passing 3000 on condition.

Rod1
Rod1 is offline   Reply
Old 8th Apr 2011, 09:06   #8 (permalink)
 
Join Date: Sep 2003
Location: Retford, UK
Posts: 469
Not had a conversion, but I have a 914 turbo in my Europa and am really happy with it, nice to have that extra boost for a short take off run. Though of course it does end up heavier than the 912S 100hp.

This conversion kit seems like a reasonable idea, but they do recommend having a full condition inspection before adding the turbo, and the $8500 is just for the kit, installation/inspection is another $2500 + parts. I guess also the warranty would also just apply to the kit parts.

If you can't sell the 912 I guess it would seem reasonable?
MichaelJP59 is offline   Reply
Old 8th Apr 2011, 14:29   #9 (permalink)
 
Join Date: Aug 2010
Location: Ecuador
Age: 36
Posts: 227
Quote:
Originally Posted by BackPacker View Post
You might want to try the LAA. There's a lot of folks there with Rotax experience.

Also, I seem to recall that Skydrive is the UK dealer with a lot of experience in maintaining Rotax engines.
Thanks!


Good link, I didn´t know that forum at all.

Quote:
Originally Posted by Jan Olieslagers View Post
I can't help wondering what kind of money you can still hope to get from your current 912 with a thousand hours on it. Isn't its full life span limited to 1500 hours?
Sorry to push back on your nice plans...
No worries………it is a pain though, having to sell this aircraft first.


Quote:
Originally Posted by Rod1 View Post
“Recent Rotaxes 912s have a TBO (time between overhaul) of 1500 hours”

Nope, it is 2000 hours (TBO) with many passing 3000 on condition.
Rod1
That is correct, even the new 914UL get a TBO of 2000 from Rotax these days.

Quote:
Originally Posted by MichaelJP59 View Post
Not had a conversion, but I have a 914 turbo in my Europa and am really happy with it, nice to have that extra boost for a short take off run. Though of course it does end up heavier than the 912S 100hp.

This conversion kit seems like a reasonable idea, but they do recommend having a full condition inspection before adding the turbo, and the $8500 is just for the kit, installation/inspection is another $2500 + parts. I guess also the warranty would also just apply to the kit parts.

If you can't sell the 912 I guess it would seem reasonable?
I guess, thinking about it………my Rotax engineer is my friend and he worked my engine from almost zero hours so if I would travel to the States to pick it up, I´d have the whole kit installed locally for a bit more than $10.000,-.
My heart still tells me to stick to the original plan though………..which was sell the plane, and buy a nice, "0 kilometers" conventionally breathing 912ULS.
Granted, my plan is to fly high up in the Andes but talking to owners of both 912ULS and 914UL…………the advantage is on the 912ULS`s side, I´m afraid.

The 914UL consumes 40% more fuel (!!!) and the power difference at sea level is negligible. In the mountains the 914UL wins, but I have seen several club members that make it up to 6000 meters with the 100 HP Rotax 912ULS………..so why wouldn´t I? Obviously, these trips would have to be planned on good weather days…….but the same goes for a 914UL, and as I said; my non-turbo´d friends take off from airstrips at 3.000 meters with their 912ULS.

The extra consumption every day, every flight; the extra maintenance $$…… I don´t know--> I´m torn.

I´m enjoying this thread though………..any more opinions out there?

###Ultra Long Hauler###
Ultra long hauler is offline   Reply
Old 8th Apr 2011, 15:36   #10 (permalink)
 
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,406
It hasn't been mentioned at all, but do you intend to fit a VP/CS prop?

From what I've heard installing an airmaster CS electric prop (or any other for that matter) makes a huge difference, particularly in take-off performance.

And it might be a retrofit that's far easier to fit on a 912UL than the 914 conversion kit.
BackPacker is offline   Reply
Old 8th Apr 2011, 16:12   #11 (permalink)
 
Join Date: Sep 2003
Location: Retford, UK
Posts: 469
Quote:
The 914UL consumes 40% more fuel (!!!)
I think that's only when you're in the turbo range though isn't it? (I think it's called take-off performance in the manual). Otherwise 914 and 912S have similar fuel consumption. Someone more knowledgeable than me would know the details.
MichaelJP59 is offline   Reply
Old 8th Apr 2011, 17:47   #12 (permalink)
 
Join Date: Aug 2007
Location: Plumpton Green
Age: 70
Posts: 737
Quote:
Nope, it is 2000 hours (TBO) with many passing 3000 on condition.
Oops! Better read the Rotax literature while waiting for the Don Francisco to sign my permiso.
patowalker is offline   Reply
Old 9th Apr 2011, 03:00   #13 (permalink)

 
Join Date: Apr 2011
Location: Hong Kong/UK
Age: 44
Posts: 3
Hi,

I currently run 3 aircraft with rotax 912's in various guises. I have the 100 hp version in my mto sport gyro which gives bundles of power and fairly good fuel consumption. Some of my friends run the 914 and I have to say the turbo is not good. I think it's an old garret they have bolted on. If I was in your position I would look at the 100 hp and forget about any add on turbo kits. KISS - keep it simple stupid. On another note they are superb engines all be it expensive to buy, well certainly in the Uk.
Catchacloud is offline   Reply
Old 9th Apr 2011, 07:32   #14 (permalink)
 
Join Date: Jan 2003
Location: BC Canada
Posts: 383
We have a couple of guys who have converted in our group. The only one I can remember was a 912UL converted to 100hp. (Non turbo) I think that turned out to be not terribly satisfactory.

Most of the guys who have 914s seem happy with them and I haven't heard too much about serious turbo problems.
ChrisVJ is offline   Reply
Old 9th Apr 2011, 18:02   #15 (permalink)
 
Join Date: Aug 2010
Location: Ecuador
Age: 36
Posts: 227
Quote:
Originally Posted by BackPacker View Post
It hasn't been mentioned at all, but do you intend to fit a VP/CS prop?
Ivoprop, Medium…………Inflight Adjustable.

http://www.ivoprop.com/inflightmediummodel.htm

Quote:
Originally Posted by MichaelJP59 View Post
I think that's only when you're in the turbo range though isn't it? (I think it's called take-off performance in the manual). Otherwise 914 and 912S have similar fuel consumption. Someone more knowledgeable than me would know the details.
Well, I don´t know. That is one of my major considerations!
I can´t find any good info on that anywhere……….
Would I be able to save a lot of fuel by running it with at, for argument´s sake; 90%??

Quote:
Originally Posted by Catchacloud View Post
Hi,
Some of my friends run the 914 and I have to say the turbo is not good. I think it's an old garret they have bolted on. If I was in your position I would look at the 100 hp and forget about any add on turbo kits. KISS - keep it simple stupid.
Thanks, but I believe the kit I was referring to is with original Rotax parts.
Crucially, the Turbo Computer is Rotax´s………
But yeah, I see your point…………I was hoping somebody had experience with this particular kit.


###Ultra Long Hauler###
Ultra long hauler is offline   Reply
Old 9th Apr 2011, 20:21   #16 (permalink)
 
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,406
Quote:
I can´t find any good info on that anywhere……….
I happen to have an old Europa brochure here with engine info on both the 912ULS and 914UL (but not the 912UL unfortunately)

Between the 912ULS and 914UL the performance figures are remarkable similar with one main exception: the "take off" curve from the 914 is higher in every respect: power, torque and fuel consumption. Obviously that's the time when the turbo is most active.

But other than that the fuel consumption for a given HP seems almost identical between the two. The graphs in the brochure aren't all that good but it looks like the 914UL is even using slightly less fuel (<5% difference) to produce a given power than the 912ULS.

I was looking at the Rotax site and it seems that you can get the original datasheets directly from them. Doesn't that help?

Aircraft - DOCUMENTATION
BackPacker is offline   Reply
Old 11th Apr 2011, 11:01   #17 (permalink)
 
Join Date: Sep 2003
Location: Retford, UK
Posts: 469
On my Europa there is the normal throttle range from 0-100%, then you have to shift the throttle lever sideways through a detent to engage the turbo and use takeoff power (115%). Advice is not to use part of this 100-115% range, you either use full take-off power or just use the normal range.

I normally cruise at 75% 5000rpm for 18-20lph. More patient people cruise at lower power settings.

Seems to be the general consensus is if you are buying new then the 912S is fine for most uses and no point paying extra for the turbo. However the original question was what can be done to uprate the 80hp 912 - can it just be upgraded to 912S spec?
MichaelJP59 is offline   Reply
Old 11th Apr 2011, 18:43   #18 (permalink)
 
Join Date: Aug 2010
Location: Ecuador
Age: 36
Posts: 227
Quote:
Originally Posted by BackPacker View Post
Between the 912ULS and 914UL the performance figures are remarkable similar with one main exception: the "take off" curve from the 914 is higher in every respect: power, torque and fuel consumption. Obviously that's the time when the turbo is most active.

But other than that the fuel consumption for a given HP seems almost identical between the two. The graphs in the brochure aren't all that good but it looks like the 914UL is even using slightly less fuel (<5% difference) to produce a given power than the 912ULS.

I was looking at the Rotax site and it seems that you can get the original datasheets directly from them. Doesn't that help?
Thanks for that link…………I don´t seem to be able to get the info I need though. I kind of hope you´re right………….
But others say that on average (normal use--> warm up, take off, cruise and landing), the consumption would be 33% higher than the 912ULS.

Quote:
Originally Posted by MichaelJP59 View Post
Seems to be the general consensus is if you are buying new then the 912S is fine for most uses and no point paying extra for the turbo. However the original question was what can be done to uprate the 80hp 912 - can it just be upgraded to 912S spec?
The way I understand it, no. The 912 UL (80 HP)and the 914 UL (115HP) are the basically the same engines………same block, same pistons, same everything.
The Turbo is the only difference, plus the exhausts and carburetors--> but internally……….same same.

The Rotax 912ULS however………the 100 HP Non-Turbo, is different though.
Different pistons, different block etc, compared to the 912 UL & 914UL, but others may be able to explain better.

Saludos,

###Ultra Long Hauler###
Ultra long hauler is offline   Reply
Old 11th Apr 2011, 22:35   #19 (permalink)
 
Join Date: Aug 2010
Location: Stockholm
Posts: 7
On Aircraft - Home you have all the information you need about fuel consumption etc for the 912 ULS and 914.

I have a 914 in my Dyn'Aéro MCR-M and I see typically exactly the same fuel consumption as with the 912 ULS except for the few minutes during take off where I use the turbo. I have not yet investigated the high altitude performance though.

Best regards
/Bengt
mmbengt is offline   Reply
Old 12th Apr 2011, 14:10   #20 (permalink)
 
Join Date: Aug 2010
Location: Ecuador
Age: 36
Posts: 227
Quote:
Originally Posted by mmbengt View Post
On Aircraft - Home you have all the information you need about fuel consumption etc for the 912 ULS and 914.

I have a 914 in my Dyn'Aéro MCR-M and I see typically exactly the same fuel consumption as with the 912 ULS except for the few minutes during take off where I use the turbo. I have not yet investigated the high altitude performance though.

Best regards
/Bengt
Thanks, nice low winger--> I googled her.
I compared the 912ULS & 914UL´s fuel consumption graphics……..and at 5500RPM they are as good as identical.
After the 5500, the 914´s consumption sky-rockets, for obvious reasons.

Yesterday I got feedback from a local friend of mine though that the overall consumption of a 914 at the club is 33% more than the 912ULS, but flying faster; the difference is realistically 28%, approximately…………

Still quite a lot………..and this goes against the Rotax graphics, assuming you cruise under 5500RPM; only using the Turbo for take off´s or high altitude action.

###Ultra Long Hauler###
Ultra long hauler is offline   Reply
Reply
 
 
 


Thread Tools


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT. The time now is 07:45.


vBulletin® v3.8.7, Copyright ©2000-2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
© 1996-2012 The Professional Pilots Rumour Network