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Question regarding Hirth Motors

Posted: Wed Mar 05, 2008 8:18 pm
by John Boucher
There was a Rans stationed at Morningstar - it had a 3 cyclinder water cooled two stroke engine - do you have any info regarding it?

Posted: Wed Mar 05, 2008 8:27 pm
by Morph
Rans S10, 3cyl water cooled fuel injected 100HP Hirth 2-stroke. Spends a lot of time flying inverted, doing rolls etc.

What do you need to know :wink: 8)

Posted: Wed Mar 05, 2008 8:30 pm
by John Boucher
This Rotax fiasco is forcing me to think of other solutions!

Is the engine reliable? Suppliers or supported in SA?

Posted: Wed Mar 05, 2008 8:34 pm
by Morph
Hirth had a bad rap on the previous motors.

This is one of two at Morning Star. He has done around 200 hours on it and it appears to be running perfectly. The TBO is 1000 hours

They are priced very well and there is a local agent. I'll try to get more information for you

Posted: Wed Mar 05, 2008 8:35 pm
by John Boucher
Technical data
Type Three cylinder two stroke (inline)

Displacement
939 cm3 (57,3 cu in)

Stroke
69 mm (2,72 in)

Bore
76 mm (2,99 in)

Max. performance
74 kW (100 HP) at 6000 rpm

Max. torque
120 Nm (88,4 ft.lb) at 5500 rpm

Mixture formation
3x Suction pipe injection

Ignition system
CDI programable

Generator power
250W, 12V

Cooling
Liquid cooling

Weight
45 kg (99,3 lb)

Start device
Electric starter

Direction
Counter-clockwise, view to output shaft

Fuel
Mixture 1:50, 2-stroke-oil, fuel min. 95-octane (RON)

Mixture 1:80-100 with BLUEMAX

2-stroke-oil, fuel min. 95-octane

Posted: Wed Mar 05, 2008 8:36 pm
by John Boucher
As you said TBO 1000 hours

The crank is guaranteed for 3 years......

ROTAX - BRP ..... are you reading this guys?

Posted: Wed Mar 05, 2008 8:40 pm
by Morph
Bad Nav, I split this away from the Hydraulic brake question


The Hirth agent in SA is Warren James and you can reach him on: 083 997 9814

BTW here is a pic of the Rans S10

Posted: Wed Mar 05, 2008 8:50 pm
by John Boucher
The advantages of being a moderator!!! :lol:

Didn't mean to hijack the thread.

The engine weight should be to the advantage of most... I was impressed by the performance. I was there when the chaps flew over to demonstrate the Jora. Yours truly Rans of course did a loop... :shock:

Was a green appie pilot then...

Where most are searching for replacements and automotive imposters, wouldn't it be wise to investigate an option like this. The only thing bothering me is the Euro exchange rate.

Posted: Wed Mar 05, 2008 8:56 pm
by Morph
His brother just put the 80 horse version into his brand new Jora. Can't wait to see how that flies.

I'll tell you, she has a really distinctive sound, almost like a hot speedboat motor. With that little RANS and the 100 horses at sea level she doesn't take of, she launches :wink: :lol:

He pops her off the ground, runs along in ground effect to build speed and then goes almost vertical for +/- 100 foot. Amazing

Price wise, the rattex suffers the same Euro woes. the price difference will always be there.

Posted: Wed Mar 05, 2008 8:57 pm
by Wargames
BAD NAV wrote:Where most are searching for replacements and automotive imposters, wouldn't it be wise to investigate an option like this. The only thing bothering me is the Euro exchange rate.
Bad Nav,

What would a engine like this run your pocket??

On performance per kg, this engine will beat about everything.

Posted: Wed Mar 05, 2008 8:59 pm
by John Boucher
So why has the engine been so quiet....

It's a great performer, fuel injected etc.

Posted: Wed Mar 05, 2008 9:06 pm
by Morph
Morph wrote:His brother just put the 80 horse version into his brand new Jora.
In fact he actually bought the 100 horse 3 cyl and found the engine to be too hot for his purposes, so they ordered a performance reduction kit, heads, cylinders etc and reduced the power down to 84 horses. Hirth also have a 2 cyl Engines in the 60 to 70 HP range. 582 replacements

http://www.hirth-engines.de/english/index.htm

Posted: Wed Mar 05, 2008 9:09 pm
by Morph
Good question. I think it does have something to do with earler models being unreliable

Maybe it's time for a change

Hirth

Posted: Thu Mar 06, 2008 6:09 am
by ZULU1
Chris/Morph, I looked at the Hirth a while back, they have serious power and they sound in my view among the best. I would say similar to the first Kawasaki triples (500ccmach1). When i looked on the web there were many incidents in the states.

BUT as engineers they fix them as always when a problem arises..Its still a two stroke though but fuel injected.

Maybe worth a look ?? The engine management is magnificent.

Paul

Posted: Thu Mar 06, 2008 10:06 am
by Morph
I had a visitor from Denmark the other day track me down at Morning Star for a chat. I met him on the SAmicro email forum. He was visiting his son and he looked me up. He flies a Savannah with a Jabi 2200 motor.

Anyway he says Hirth has a bad reputation in Denmark. Again he was referring to the previous models.

Truthfully speaking the Rans guy had a problem right in the beginning. In November 2005 he was flying to Overberg - Bredarsdorp for the TDFC fly in when the rubber dounut coupling driving the prop sheared off and he had to do an emergency landing in a field. They stripped his brother's motor for the part, fixed it and flew it out and home. Since then no issues and he flies every weekend, sat and sunday. That plane literally prop hangs and the motor really works hard.

2.5 years later and still running flawlessly

He is running the 3701es

From what I can see the 2703 is the problem child, breaking cranks, bearings seizing, engine seizing etc all within the frist 100 hours. also they do not like to run upside down, like on a Challenger.