D-Motor

[Kyle Communications]

Excellent information Nick...what have you heard or know about the 6 cyclinder version?

 

 

[xair1159]

I have photos of the 6 cyl at Popham microlight show, if I can work out how to attach them I will post them later, but it generally looks identical to the four.

 

They have the engine + exhaust with a plate attached carrying all accessories (oil tank is on the rear face) except a water radiator.

 

Weight is a shade under 77kg for 128 hp, so add the rad and fluids and I would guess somewhere around 85kg total ready to run.

 

Main user of the engine so far is a German helicopter with contra rotating rotors and no tail rotor - I will post a link later.

 

I have flown a microlight (!) fitted with the 6 cyl but only for a couple of hours. The prop fitted was a poor match and couldn't handle the power.

 

The cooling wasn't sorted so high power runs had to be limited duration, but despite all this it was very smooth with plenty of power.

 

It sounded superb and is worth buying for the noise alone!

 

Nick

 

 

[bexrbetter]

Great info Nick, thanks.

 

 

[Kyle Communications]

thanks Nick ..I look forward to the pics if you can work it out

 

 

[cooperplace]

Mister Sir best foreign friend, do best job manual we do number 1!

the owners manual on my Kawasaki 4 many years ago, with twin rear shocks, said that a fault in one shocker "would convert machine into evil device".

 

 

[Litespeed]

the owners manual on my Kawasaki 4 many years ago, with twin rear shocks, said that a fault in one shocker "would convert machine into evil device".

My memories of the Z1 and GT550 were you only had to turn the key for that to happen. We always joked how great a machine they would be if they didn't put a hinge in the middle.

 

 

[xair1159]

Right, I have to admit failure, tried the images and file upload thingies that want URL's etc. without success.

 

Please can someone give me an idiots guide to attaching photos to a post.

 

Nick

 

 

[fly_tornado]

in the bottom right "upload a file"

 

 

[Marty_d]

the owners manual on my Kawasaki 4 many years ago, with twin rear shocks, said that a fault in one shocker "would convert machine into evil device".

If it was a Suzuki I'd say no fault at all was required for that to happen.

 

 

[Soleair]

Gixxers, maybe. But my little DRZ400 loved being treated rough - kept asking for more.

 

 

[Bruce Tuncks]

After about 50 hours I was told I was treating the Jabiru engine too gently. I replied that this policy worked ok on the missus.

 

Apparently aero engines are different to wives.

 

 

[Marty_d]

Difference is, there's no such thing as a missus who's too rich.

 

 

[Soleair]

And those who are too lean are getting a bit thin on the ground.

 

 

[xair1159]

Magic! Thanks to fly tornado.

 

Photos of the D-Motor 6cyl on its display stand at Popham. The red tape was just to stop it swinging round in the wind.

 

Weight includes every accessory except exhaust and fluids, the oil tank is on the rear of the plate.

 

Nick

 

 

 

 

[xair1159]

Correction, that should be radiator and fluids, you can just see the double can exhaust below the engine.

 

 

[fly_tornado]

looks good! very compact, compared to something like a subaru, which gives you better options for placing radiators

 

 

[facthunter]

On a "Flat" (horizontally opposed), motor you need the intakes below the engine, generally and especially if it has carburetters., and the shorter the intakes the better. Sidevalve motors are the least "tall" of the mechanical valved motors, particularly the Overhead cam engines, without rockers. Also much simpler and lighter. by far. Nev

 

 

[fly_tornado]

I was a bit sceptical about the idea of a flat head but with modern design and casting technology and that dual ignition, this engine looks a real winner

 

 

[facthunter]

They are compact but so is a Vee (4 or 6) specifically designed, and the block more rigid with integral cylinders once you go liquid cooled. Nev

 

 

[Downunder]

You would think that with all the troubles Jabiru are having with their engines (casa, etc) and with a d-motor already fitted to a Jabiru, it would have been an ideal time for a marketing push for the d-motor here in Aust.

 

92 hp take off power and 88 constant at 52 kgs.

 

Perhaps the price of $20 000 plus has scared off the punters?

 

And I'm not sure if that is FWF or just engine.

 

Of course some value would be salvaged from selling off the jab engine and bits and pieces.

 

The 6 cyl looks good at 125hp. (Especially without forced induction) Mfg website shows 18 800 euro, so would perhaps be over au $30 000 delivered here.

 

Will be interesting to see Rotax's pricing of the upcoming 915is at 135 hp turboed.

 

 

[facthunter]

The 2200 Jab was definitely developing 85 HP at one stage. They have retarded the ignition.(which I don't agree with) and lowered the compression since then but 80 HP should still be about right. The "D" motor is a much bigger displacement, liquid cooled engine, It has to be less efficient because of the combustion chamber design. You can't avoid it thermodynamically, and you have the complexity of liquid cooling. (as well as the advantages). It should be a less critical motor to run, because it's liquid cooled. Valve seat and local cylinder distortion might be a concern. Nev

 

 

[bexrbetter]

The "D" motor is a much bigger displacement, liquid cooled engine, It has to be less efficient because of the combustion chamber design.

But at those compression ratios, not a huge difference.

 

At the end of the day only the numbers count and the D Mtr is surprisingly competitive in everything except the all important price.

 

 

[facthunter]

True , as long as people realise it will never be the best in the fuel stakes. It could have had a longer stroke and swing an even bigger prop. Nev

 

 

[Litespeed]

I expect the Rotax 915is will be easily in the $35-40,000 range when landed and has the FWF bits added.

 

But could well be a lot more.

 

 

[bexrbetter]

I expect the Rotax 915is will be easily in the $35-40,000 range when landed and has the FWF bits added.But could well be a lot more.

Geezus.