Has anyone installed a D-Motor in a 701?  My 701 is currently flying with a Jab 2200 and I was looking to add a bit more power at a lower RPM.  I am especially interested in the performance of a 701 with a D-Motor.

Thanks,  Bill Barton

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I'd like to take this as yet another opportunity for a "teaching moment:"

First, be assured that my comments are not directed at any specific member or their posts!

Second, this would be an excellent excuse for all members to go back and review the Member Rules.

Third, please keep all comments factually based - we don't allow "flaming" or casting aspersions on each other.

Fourth, be polite and considerate of other members.

Fifth, when you write a post, take a long, deep breath, sit back, re-read it, and think about it before you hit that "Add Reply" button! ... I do!  ;>)

Thanks to everyone for participating in these forums!


Zenith.aero Forum Moderator

Charles, I doubt your concerns with the Viking Mitsubishi engine are justified, and cannot imagine Jan at Viking being flippant unless given cause.   

William, the D-motor looks to be a good engine to consider, as is the Viking or any other.  I wish you well on your choice of engine.

500 Viking engines sold and still this kind of blather. No facts just ad hominem attacks based on irrelevant 10 year old history.

No rebuilds for the 90HP??? Then why are Mitsubishi 3 cylinder bearings available online. Sure look like metal to me. If this FUD tale was true, Mitsubishi would be bankrupt. Just one shop guy's unsubstantiated opinion being fed to the internet as fact. Jan's comment about replacement is valid should you lose the core engine. Far from being flippant, Jan openly says the exact same for the Viking 130 Honda conversion.

The D-Motor is a solid choice but cost is Rotax high. The D-Motor designer was one of the UL Power Engine founders, but they split based on engine design philosophies. If price is not a factor, I would go with the D-Motor. But saving $10k is helpful to most human beings. It is good for all of us to have alternatives.

Sure would be nice to see some posts about the D Motor.

R Michael Moore (and others) this is supposed to be a thread about D-Motor in a 701. This is not a thread about pros and cons of Viking engines.


This is exactly what John Austin just today asked not to be done.   Your comment directed to me is personal in nature.   It is patently obvious that it was not via my postings that this thread was taken off topic.   

I understand your concern and wishes, but given the context my directing readers to facts was relevant to fairness and completeness.   I did not interject any commentary which should have been a clear indication of my intention to provide a minimum of context for future readers.   There was no need to call anyone out by name here.   

My postings also contained only good comments about the D-Motor.   

On that note, readers will need to search via Google into the EU market to find Zenith and other aircraft flying this engine.   I have done so and only found extremely positive comments about the D-Motor, its design and operation and the service / support provided by the Company.   I exchanged emails over many months directly with the company owner/designer, the present and previous USA D-Motor representatives, and also two owners flying this engine in Europe.   Both were extremely satisfied, delighted even with their engine choice.   The 4 cylinder LF26 model is fully ASTM compliant.   D-Motor has obtained capital from China and so appears to have the needed funding to prove itself over time.      

There is a D motor rep. in Tn. His name is Steve McKamey. I have his number if you would like to call him. He is a engineer, and may be able to help you. The only other rep. in N. America, Is in Canada.

I just went to their site. Wow! It's a flat head engine!  That's different for an aircraft engine.

The answer to engine selection is easy-choose UL Power! I have been enjoying my 350i with over 165 hours in the past year. Good performance, and my home base is at 4500 ft. Monday when the outside temp was under 20 degrees F my Cruzer really climbed! Had to throttle back to the airspeed under 115 mph.

I have not heard any traceable horror stories about this engine, I know of a leaking gasket issue or two, but nothing inherent with the design. They list their Servce Bulletins online for anyone to read. Their US rep is easy to deal with and he is not afraid to refer you to an AP when he does not have the answer to your mechanical questions. If we had cheap access to higher octane fuel I would suggest the 350is. It has about 10% more power than the 350i, same engine, shaved higher compression heads. And best all, the 350 is a pretty engine to look at!



Nice video from Europe about 2+ years back with Zenith 650   Not a 701 but for D-Motor fans shows good performance.   1000+ ft climb rate reported by owner.   Left the tarmac in about 5 to 6 seconds.   

Price is very high.   That is what I see as the only short point.    


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