# Non- Biased Engine Reviews -Aeromomentum

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#### ToddK

##### Well-Known Member
HBA Supporter
Lot of people talking about Aeromomentum. Any real life reports from pilots flying those Suzuki's? Any numbers on how many are flying? Any idea how many have been sold?

#### TarDevil

##### Well-Known Member
Lot of people talking about Aeromomentum. Any real life reports from pilots flying those Suzuki's? Any numbers on how many are flying? Any idea how many have been sold?

#### Oliver

##### Member
Lot of people talking about Aeromomentum. Any real life reports from pilots flying those Suzuki's? Any numbers on how many are flying? Any idea how many have been sold?
I'm somewhat hesitant to respond to your post, since I joined the forum just recently and don't want to come across as somebody who joined only to trash talk AeroMomentum.

We ordered an AM15 with the Zenith FWF package in 2017, just before AirVenture, paid for everything in full and finally gave up earlier this year, after spending a lot of hours, trying to make things work and accepting a huge financial loss. I have attached the details of my listing from February, with several images, showing the firewall forward 'kit' as well as the timeline. As of today, we still haven't received the missing 'nostrils'.

A few notes in addition to that:
• I didn't find brand name labels on any of the mayor components. The fuel rail is made by UAES, a few sensors by Bosch, but that's about it. The word 'Suzuki' or markings of any of the typical OEM suppliers like Denso, Delphi or Bosch aren't anywhere to be found. Mark shared the manufacturers of the fuel pumps, starter, alternator and coil pack with me, which were all Chinese producers of aftermarket components. He claims that they are also the OEM manufacturers, what may or may not be true.
• We were promised a list with part numbers, in case we wanted to source service parts elsewhere. Despite of SEVERAL requests, we however didn't even receive the OEM part numbers for the starter, alternator and coil packs. I wanted to replace them as I doubted their quality and since a fellow builder in Australia had massive problems with his. According to Mark, all of his problems were self inflicted, what again may or may not be the case.

I'll leave it at that.

We have pulled the AM15 and are currently in the process of installing a Rotax 912 ULS with the Zenith FWF kit.

Oliver

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#### Oliver

##### Member
Deleted... Info provided in Oliver's attachment.
I also wanted to make it clear that I still think that Mark is a nice guy and that the engine itself is probably fine.

My frustration was primarily caused by the massive delays we experienced, AeroMomentum's inability to get their vendors, e. g. for the cowling or the engine mount sorted out, and the, in my opinion, poor fit, quality in incompleteness of the FWF components. Their decision to go with no-name engine auxiliary components and a DIY grade ECU in a plastic housing, weren't confidence inspiring either.

I attached in my previous post the spec sheet for my listing, from when I posted everything for sale earlier this year. It contains quite a few pictures of everything that came with the FWF forward 'kit'.

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#### Oliver

##### Member
I see the pdf read like a for sale ad.Where are you located?
I'm in Novi, Michigan, USA.

This was the spec sheet for the listing I posted in February. I sold everything in the meantime to a fellow builder from Canada. As the border is currently closed, it is still sitting in our hangar, in case you want to check it out (I guess you won't if 'nz' stands for New Zealand ).

#### Air Trikes

##### Well-Known Member
Lot of people talking about Aeromomentum. Any real life reports from pilots flying those Suzuki's? Any numbers on how many are flying? Any idea how many have been sold?
I build Suzuki G10, then G13 from 1998. I sold 80+ G13BB engines for different aircraft, hovercraft and airboats, more than 300 conversion kits. Not too much maybe but enough for some statistics. I know at least 3 companies started to convert Suzuki G series engines looking at my results (from China, USA, Russia). Unfortunately it is not easy to find "made in Japan" engines and components now. I'm not very optimistic yet about using Chinese engines, gearboxes or other components. This is first hand experience. More info Air Trikes: Engines and Conversion Kits.

#### aeromomentum

##### Well-Known Member
Since this topic is about Viking, I did not want to sidetrack the discussion. But since Aeromomentum has been introduced to this I would like to reply.

In the interests of full disclosure I would like to bring up all of our issues and how we have solved them.
So far we have had 5 issues and using the Japanese concept of Kaizen we have been correcting and improving our engines.

1) Suppliers
As Oliver has stated, we have had supplier problems mainly with US based cowling suppliers. We have solved our cowling supplier issue after a few attempts and finally have qualified suppliers in place. Our first batch of 750 engine mounts were substandard but again got another supplier and they are now beautiful. We have made a lot of other improvements since Oliver bought his FWF parts.

2) Alternators
All of the parts we use when we build the actual engines are from Suzuki and their qualified suppliers, except the alternator. The alternator was not used by Suzuki so was not a Suzuki OEM part. At one time we were sourcing them from China but now we source them from the USA and they are made by and labeled Nippon Denso.

3) Starters
The Suzuki starter is a known issue with Suzuki for many years and there are known fixes including clickystart.com. When wired exactly per our instructions they are very reliable. If not wired per instructions they will fail and at times take the alternator with them. We now use a non-Suzuki geared starter that is not as susceptible to wiring deficiencies and is much more robust. It is about 1lb more weight.

4) Fuel pumps
We were using a fuel pump from an ISO rated supplier and sold over 1000 of them with just 2 failures. Then we got a bad batch. Now we source TI/Walbro pumps in the USA.

5) Overheating
This was never an issue with the actual engines, radiator, etc. The two causes have been air in the system from improper burping and lack of airflow through the radiator. When properly burped and installed even our high power engines can provide sustained 100% full power climb on 120F days without even a hint of overheating. I doubt that a Lycoming can do this. We have changed the header tank and it's location to make burping the system much quicker. While we use the older system in our 701 without any issues we do offer a free or low cost upgrade kit to our customers.

Our ECU has had zero failures. Yes, the case is plastic and so looks cheap but this makes it light and compact. For me it is function first. One of the main reasons we chose this ECU is the high relaibility Amp Seal connector. Most of the other aftermarket ECU's use mush less reliable D connectors.

I know it is very popular to bash China. Lots of low cost junk does come from China. But keep in mind that China can and does make world class products. They are one of just 3 countries to put men in space. Most major manufacturers like Mercedes, Lexus, GM, Ford, Tesla, VW, Suzuki, Honda, Bosch, Apple, etc, source or make many or most of their parts in China. The first cars exported to Europe from China were the Honda FIT's. Today, manufacturing is global and many people do not know where parts come from. For example the Honda L15 Earth Dream engines are all made in Malaysia, not Japan. So even if a car is assembled in Japan, many major parts are globally sourced. As Air Trikes said "it is not easy to find "made in Japan" engines and components now." Especially if you are looking for a newer Honda L15 since they were never made in Japan. But this is not an issue! The key is quality control and any company in any country can do this if it is important to them like it is important to us.

#### rv6ejguy

##### Well-Known Member
One of the main reasons we chose this ECU is the high relaibility Amp Seal connector. Most of the other aftermarket ECU's use mush less reliable D connectors.
Mark, I usually agree with what you say here but this is just wrong. We have sold over 10,000 ECUs with collectively something over 20 million hours on them over 27 years. Zero D sub failures in that time. A bunch used in multiple Baja 1000/500 and SCORE race trucks and buggies which can pound you so hard, people have broken ribs. This is a FAR more extreme G and vibration environment than aircraft ever see.

You can't get any more reliable than that...

Our 6th generation ECU, under final development now, will also use the same D subs for the main, Hall sensor and programmer connections that the current EM-5 does.

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#### rv7charlie

##### Well-Known Member
Hmmm...
Any chance both connector techniques are correct?
Where is the SDS controller mounted (hot or cold side of firewall)?
Where is the Aeromomentum controller mounted?

I use subDs for almost everything, and they are extremely reliable (except the occasional pin backing out of a connector; likely assembly errors). But I wouldn't want to use them on the hot, potentially wet side of the firewall. I'm not familiar with Amp Seal (at least by name) but if it's specifically designed for FWF applications, I can see the motivation to use it there. I can't remember when I've had an issue with FWF connectors in any of my road vehicles in literally decades.

#### Oliver

##### Member
[...] I'm not familiar with Amp Seal (at least by name) but if it's specifically designed for FWF applications [...]
Ampseal connectors are used by Caterpillar and John Deere. Their engines oftentimes operate in extremely harsh conditions.

#### aeromomentum

##### Well-Known Member
Mark, I usually agree with what you say here but this is just wrong. We have sold over 10,000 ECUs with collectively something over 20 million hours on them over 27 years. Zero D sub failures in that time. A bunch used in multiple Baja 1000/500 and SCORE race trucks and buggies which can pound you so hard, people have broken ribs. This is a FAR more extreme G and vibration environment than aircraft ever see.

You can't get any more reliable than that...

Our 6th generation ECU, under final development now, will also use the same D subs for the main, Hall sensor and programmer connections that the current EM-5 does.
I very much could be wrong. My understanding of D-sub connectors is based on information told to me back in the 1980's and maybe was from a biased source and could now outdated. I would also think that even slight differences in the wire strain relief method could have an impact. It is hard to disagree with 20 million hours without failure!

#### rv7charlie

##### Well-Known Member
There are multiple varieties of D-sub/subD/etc. The gold standard (literally) are the machined pins (made from solid stock) with gold plated contact surfaces intended to be crimped onto individual wires, and then inserted in the multipin body (normal use are some variation on plastic, but ceramic are available). Only real downsides are that I'm not aware of any weather-proof housings in the 'D' shape (though the pins are used in some 'Cannon' style round connectors), and a current limit of about 7 amps per pin for the machined pins (but you can 'ballast' multiple pins for increased current handling).

Various quality levels available moving down from there, with rolled crimp style gold plated pins (supplied by some experimental avionics makers and likely others), to tin plated rolled crimp pins, to tin plated solder cup pins permanently integrated into the body. Those can be pretty cheesy; could be that your '80s info was based on those.

BTW, I didn't see the controller in the pics earlier. Who makes it?

Charlie

#### rv6ejguy

##### Well-Known Member
I very much could be wrong. My understanding of D-sub connectors is based on information told to me back in the 1980's and maybe was from a biased source and could now outdated. I would also think that even slight differences in the wire strain relief method could have an impact. It is hard to disagree with 20 million hours without failure!
Yup strain relief is 90% of the battle for reliability. As another data point, our main test bench finally had the female DB25 wear out after 15 years in 2009 after an estimated 15-20,000 connect/disconnect cycles. It was certainly never designed for this but shows how robust they actually are.

#### aeromomentum

##### Well-Known Member
The comparison between GDI and port injection is relevant. Unless I am mistaken, the base Viking engine on at least one model is a stock Jazz/Fit Motor.

View attachment 111611

This motor has a compression ratio of 13.5:1 which simply cannot run in an aircraft with port injection without detonation. If port injectors put in the full fuel charge prior to the compression stroke then a high compression ratio will increase gas temperatures. Boom. Detonation.

Not so much with direct injection. With GDI the fuel is injected during the compression stroke and can be timed not to meet combustible stoichiometry until the spark triggers the flame front. And even during combustion, with GDI more fuel can be added to increase/decrease/time optimum PCP.

All good stuff for cars, however I cannot think of a single successful aircraft motor that runs 13.5:1 and successfully maintains detonation margins even with GDI. Certified engines require 12% fuel margin from detonation on a standard hot day across all throttle settings and at coolant temp limits. With 13.5:1 that would require a lot of fuel ROP. I believe Jan programs well ROP across most power settings however I have never seen a test to AC 33.47-1 so its hard to know. In fact I have never seen ANY tests from Jan except static thrust. However the unofficial GPH numbers I have seen all point to BSFC numbers >.45/lb/hp which is rich, rich, rich but with 13.5:1 probably needs richer still. So much fuel probably kills any efficiency benefit of GDI and probably robs power too. So the temptation for Jan is not to do it, and hence get closer to detonation margins from such a high compression engine. Made worse particularly if run on Mogas which has way too low octane for use in the air.

Of course if the original Honda programming and knock sensors were installed then the issue can be avoided however O2 exhaust sensors are not compatible with leaded fuels so Jan removes them. No Lambda monitoring. I believe Jan also removes all the knock sensors too. No knock monitoring either. So the detonation margins are blind and rely on Jan's fixed programming of the ECU. Across the huge variety of engine operating conditions, if the needed generous ROP limits are ever wrong or too fine, overheating and engine destruction from detonation can result. All without anything on the panel to alert except strangely high coolant temps, excessive PCP and PSRU harmonic issues thereafter.
I am sorry but this is not true for a number of reasons. First, at high power and high RPM the GDI is also injecting during the intake stroke and has the same near homogeneous air and fuel mixture so when the piston is approaching TDC you would have the same conditions for detonation with both GDI and MPI. This would be true even if the fuel was being injected only during the compression stroke since max pressure happens near TDC. The real reasons that modern engines can run higher compression are valve timing, squish, quench and knock sensing. Also compared to legacy engines the lower cylinder head temperature, smaller bore and higher RPM help. This can and has been done with both GDI and MPI. Especially if you know that the engine will never be required to produce high power at lower RPM you can tune to prevent detonation very simply. When used in a car, the valve timing also helps with this.

FYI, the example you provided with 13.5 compression says MPI and not GDI.

#### Geraldc

##### Well-Known Member
and set several of the engines on a test stand and run them at full power until they failed and record how long they lasted
Aeromomentum have done this by using airboats as test beds.

#### proppastie

##### Well-Known Member
Log Member
Aeromomentum have done this by using airboats as test beds.
their own boats or were the customers testing the un-tested products?

#### Arkan

##### Well-Known Member
Aeromomentum have done this by using airboats as test beds.
that would be a good test for them, I was thinking more of a stationary stand. Mount and engine with a prop, run it up to take off power and let her run until she breaks.

#### Geraldc

##### Well-Known Member
their own boats or were the customers testing the un-tested products?
their own boats or were the customers testing the un-tested products?
from Aeromomentum website."
We have been using these engines in boats and airboats since 2008 and have installed hundreds. These boats have been delivered all over the world including the US, China, Brazil, Russia, Pakistan, Australia, South Africa and many other countries. Many are used for tour and rental operations that use them hard and cannot tolerate down time. Only after years of experience with these G series engines have we developed our aircraft engines."

I am on no way associated with the company.

#### aeromomentum

##### Well-Known Member
I would love to run one of my engines at full power until it fails. A customer (airboat) went 4000 hours. Admittedly, it was not always full power. But also it had very limited maintenance. So 4000 hours at full power with regular oil changes should be possible. Assuming 6gph (on our 100hp at full power) and $3/gal the fuel alone is$72,000.00. We have 8 versions with most being more powerful and thus using more fuel. So about \$1,000,000.00. Just for the fuel.

But this is way more than what is required for certified aircraft engines. According to §33.49, engine certification endurance requirements are 150 hours total test run time! Of this 150 hours only 105 hours is at max power. We have done more than this and inspected for wear.

#### proppastie

##### Well-Known Member
Log Member
We have done more than this
would that be your company or a compilation of air boat customers......if your company.....any issues especially with the reduction? 105 hr max power with a test club no issues is very impressive.