Yamaha Genesis engine on a Dominator.... here we go!

Carl,
He needs to put rickshaw wheels on it too right LOl. He was talking about getting his CFI and teach in it. He will probably need those shocks to save his machine.
 
Looks great Ron. I would wonder though if that engine mount that is meant for a 618 or 582 can handle the extra weight in combination with the much larger stress induced on the support structure. Seems to me that when you see subarus, VW's, and similar engines that produce that amount of horsepower they have much beefier engine mounts. Some of those little welds and a handful of 1/4 bolts are gonna be put to the test. Rotax 912 mounts on other gyros have much more substatial structural integrity than one designed for a small two stroke engine. Just a thought.... looks great on that machine though.
 
Major modifications & Airworthiness Certification

Major modifications & Airworthiness Certification

Adam Helwich alerted me to this thread. I have been quite busy and haven't spent as much time around here as I'd like to.

Regarding "Major Modifications", everything I've read here has a shred of truth in it.

The facts are:

YOUR Operating Limitations (every EAB & ELSA aircraft has them issued as part of the Airworthiness Certificate) are the rules for YOUR aircraft. It doesn't matter what I or anyone else tells you the current rules are, these are the rules for your aircraft.

In the 10 years I have been a DAR I have seen the boilerplate for the Operating Limitations change several times. Mostly for the better.

YOUR Operating Limitations tell you that they can be changed (upgraded?) and how to go about it............. read your OPS Limits

Here is the actual wording from the Ops Limits of N618SD:

(16) After incorporating a major change as described in § 21.93, the aircraft owner is required to re-establish compliance with § 91.319(b). and notify the geographically responsible FSDO of the location of the proposed test area. The aircraft owner must obtain concurrence from the FSDO as to the suitability of the proposed test area. If the major change includes installing a different make and model of engine or propeller, the aircraft owner must fill out a revised Form 8130-6 to update the aircraft’s file in the FAA Aircraft Registry. All operations must be conducted under day VFR conditions in a sparsely populated area. The aircraft must remain in flight test for a minimum of 5 hours or for the time the FSDO assigns. Persons nonessential to the flight must not be carried. The aircraft owner must make a detailed logbook entry describing the change before the test flight. Following satisfactory completion of the required number of flight hours in the flight test area, the pilot must certify in the records that the aircraft has been shown to comply with § 91.319(b). Compliance with § 91.319(b) must be recorded in the aircraft records with the following, or a similarly worded, statement: “I certify that the prescribed flight test hours have been completed and the aircraft is controllable throughout its normal range of speeds and throughout all maneuvers to be executed, has no hazardous characteristics or design features, and is safe for operation. The following aircraft operating data has been demonstrated during the flight testing: speeds Vso ______, Vx ______, and Vy ______, and the weight ______, and CG location ______ at which they were obtained.”


Here is the applicable CFR (FAR)

§ 21.93 Classification of changes in type design.
(a) In addition to changes in type design specified in paragraph (b) of this section, changes in type design are classified as minor and major. A “minor change” is one that has no appreciable effect on the weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product. All other changes are “major changes” (except as provided in paragraph (b) of this section).

It's all there in black and white.

We have to start reading this stuff. Our "outlaw" days are over. The FAA gave us every opportunity to get legal and expects us to stay legal.

I believe the fine for operating an improperly registered aircraft is $1500. per operation (takeoff). In a recent case the FAA used You Tube video as evidence of illegal operations. I believe there were 6-8 takeoffs of the illegal gyroplane posted on You Tube.

A well known gyro builder documented the building of his gyro and sold videos of the construction and test flights. Something about his test flights caught my untrained eye immediately. Be careful out there.
 
Thank you Tom!!!
I'll save a copy for posting on PRA new info site!!
 
Could longer shock brackets be made to move the shocks out an inch to clear the mount?
 
Ron you know Todd is a personal friend right? I have no idea who that impostor is :)
On a more important note, No idea what this exhaust would cost, but take a look at this site www.hartmaninc.com. Lightweight exhaust for a Yamaha nitro snowmobile.
I bet Todd just came off his seat, he-he.

Hi Todd, I agree with everyone here, excellent craftsmanship.
 
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Looks great Ron. I would wonder though if that engine mount that is meant for a 618 or 582 can handle the extra weight in combination with the much larger stress induced on the support structure. Seems to me that when you see subarus, VW's, and similar engines that produce that amount of horsepower they have much beefier engine mounts. Some of those little welds and a handful of 1/4 bolts are gonna be put to the test. Rotax 912 mounts on other gyros have much more substatial structural integrity than one designed for a small two stroke engine. Just a thought.... looks great on that machine though.

That was one of my concerns as well. Ron told me that he ran this by Ernie before I built this bed mount and Ernie thought it would be fine. One thing that greatly strengthens this bed mount over stock is the upper clamp I installed so you now have double the mounting on the mast as before which also triangulates the load and stress. The way it is set up now the thrust of the motor is transfered around the motor directly to the mast itself.

The two mast clamps could in fact hold up the motor on there own, the rest of the motor mount supports the rear of the motor, counteracts torque in conjunction with the upper clamp as well as supports it form side to side forces.

If anyone can show good reason that this motor mount bed even has the possibility of not being sufficient in strength I will immediately build Ron a stronger one at my cost.

Keep looking guys, your input is worth gold to me.
Todd
 
On a more important note, No idea what this the exhaust would cost, but take a look at this site www.hartmaninc.com. Lightweight exhaust for a Yamaha nitro snowmobile.
I bet Todd just came off his seat, he-he. QUOTE]

This one looks a real can of worms!:wacko:
It cost $820.00 and an extra $350 for the coating.
 

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Not quite what I meant. look at the 2008-2009 Nitro column, they show a lightwieght muffler. Seeing what that cost it may not be worth the trouble.
 
Paasin" Thru they have a simple supercharger that kicks the 120 hp Yamaha up to 200hp. and one that kicks it up higher to the 220-240 hp. (2 place heavy gyro HP).
 
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Could longer shock brackets be made to move the shocks out an inch to clear the mount?

Tim,
that is what I was thinking as well, it seems to be the simplest to do. I bet Ernie could tell him right away if it would have an adverse effect.
 
That was one of my concerns as well. Ron told me that he ran this by Ernie before I built this bed mount and Ernie thought it would be fine. One thing that greatly strengthens this bed mount over stock is the upper clamp I installed so you now have double the mounting on the mast as before which also triangulates the load and stress. The way it is set up now the thrust of the motor is transfered around the motor directly to the mast itself.

The two mast clamps could in fact hold up the motor on there own, the rest of the motor mount supports the rear of the motor, counteracts torque in conjunction with the upper clamp as well as supports it form side to side forces.

If anyone can show good reason that this motor mount bed even has the possibility of not being sufficient in strength I will immediately build Ron a stronger one at my cost.

Keep looking guys, your input is worth gold to me.
Todd

Sorry if I sounded a little to brash in my critique of the mount. In fact, I can assure you I will purchase a mount for my gyro that I just picked up from Ernie when you have one avail for purchase. My machine is identical to Rons. I don't want to speak for Ernie but when I was down there to pick up my gyro from him we spoke about the Yamaha engine in some depth. He had told me that he was concerned about the engine being used on the 618 engine bracing. I asked because I know that engine is what I would be interested in when I am done with the 618. I am by no means a fabricator but more of an assembler like Ron and really appreciate the ingenuity going in to this project.
 
Why not get some nice coil over shocks with that might even have a rebound adj to them?
and forget the air springs!
 
Ron,Racer,and others involved in this build process, CONGRATS TO ALL !!:first:

Man it sure looks good, Nice workmanship. I love the prerotator set up. Ron-what RPMs are you going to get out of it now? will it be the same as before?
It sure looks like someone has put a lot of thought in the makeing of that motor mount system, Thanks Ron for the picks, I saved just about all for future ref. in a album.

Matt - YOUR'S IS NEXT...:drum:
 
I am almost certain mine will get a yamaha one day soon. I will beat up the 618 and watch to see how this all works out with time. I am interested seeing if any bugs have to be worked out and then jump on this.
 
This thread is like a real good suspense thriller. I can't wait to see what happens next............................................ :spy:...........AWESOME
 
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