Yamma-Fox

Thumbs up!

Got measurements on that scoop?

Yeah man!
Looking forward to seeing how you finish this up!

I have no desire for a show plane either.  Just a nice one.  So I like the way you think!
 

Following this.  Keep posting up your cowl build!  I have some cowl mod to do and this is really helpful.

That's a good report.  Yeah my research might have been lopsided due to the old "negative experience collection pool" effect that internet forums tend to magnify:
Example: There may be 100,000 Ford 6.0 Diesels out there, 95,000 of them run great and owners never visit the forum.  But the forum has 5,000 reports of head gasket problems so you read that and figure it is a 100% problem when it's actually 5%.

I always liked the idea of Jabiru, but research (in terms of reliability) kept swaying me away.
Anyone here swear by them... I mean in a good way...  not "swearing" while  standing "by" them
 
 

Yeah I also made up my facebook alais (Anatoli) for keeping in touch with this hobby ONLY.
Otherwise I really am an anti-FB guy too!

Thanks guys!
I didn't use a jig, just built off the firewall with oversized tube (3/4") at the bolt up locations to allow for a little warpage and got lucky... things only moved about 1/4" so those small mounting bolts are just a little offset in the 3/4 tube.  I will custom grind some brass bushings to fill the "eccentric" gap (see photo of the off-center gap below).
I really wish I could scan this thing to a file in order to share it for anyone else with a KF 5-7, but I just don't have acess to something like that.

Getting ready to put all my pieces together!
I finally got my big parts together, ending today with getting my mount back from the welder and powdercoat guys.
Below is a pic of the "big 4" custom components in a Yamaha conversion:  Motor Mount, Airbox, Header, and Throttle Reverser.
Anyone else following in my footsteps will have an easier job these days because we have a lot of people in the Yamaha community who have stepped up in offering help with these and other fabricated parts.  For more info, including contact info for FWF parts, join up in the "Yamaha Aircraft Conversions" Facebook group.
 

  Nope!
But I've got big ideas about going up to our Lake of the Woods island property with this puppy.
I tell you that but the Lake Amphibian my dad and I own only gets up there every few years... and it has 4 seats and a huge cargo bin!
So I'm sure it'll just  be a novelty of a trip for the KF!

My plan is to go with the uavionics skybeacon and rewire my (all led) nav lights to my radio master so I don't forget to have it on.
Anyone here actually running the skybeacon?

Your a tough SOB Ed!   I remeber you've been through a lot in this life, but maybe that was all special training for this big fight right now.
This one's been extra tough but I'm not worried!   See ya back here soon!

Yeah wow!  Jim grab it and put an Apex in it.  Some big tires, a $5k panel and you could flip it for big bucks!   
That is, If you still want to sell after you find how much fun flyimg it is!  

Thanks everyone for tuning in here and watching over my work.  I really do appreciate it and welcome the experienced oversight!
Most of my info is well known to the old pros on this site I'm sure, but hopefully I can contribute a little here and there sometimes to pay ya'll back for watching over the rookie.
And hopefully this "ordinary guy" build thread will inspire others that: "if THAT guy can do it.... I could do it!"   LOL 
Here is a video I made of coping the tube:
 

The one simple tip I've got for ya (after a couple ground loops of my own early on) is to chant in your head "go around... go around.... go around" as you come down to touchdown.
If it doesn't setlle on just right... or if it gets the tiniest bit squirreley on rolllout,  put some power in (bringing the tail back to life) and go around.
With that in my head (cocked and loaded to go around) I haven't had any further stories to tell...  but I have gone around plenty of times! 

Yep, yep, and...  YEP!

Thanks for the thanks!  I'm just glad if I can help other people out (half as much) as I have been helped along in this project!
That R1 box has only been used by one other AFAIK.  That is "Yooper Ed" here in the group, but he doesn't frequent the forum often.  According to him, it merely required a jetting change (he drilled out his main jets to about 180 size) and he says it runs great.   His info is why I chose the R1 box but if you have room you that snowmo airbox will work great as well.
But as far as the jetting / tune, no matter which airbox you choose,  you will have some fine tuning to do and really should run an AFR guage to get precise jetting for your particular setup since it seems each plane runs just a titch different due to ram air effects and exhaust system differences.  Just be  sure you dont run avgas on the AFR's O2 sensor!
Hey, start up a new post with your motor project!  I'm really looking forward to seeing it come together!!

Damn.  I was looking for a good new cheap and available psychotropic.... all the other good ones have been banned.

Just guessing here, but if that part is required for adding strength you'd probably want to get the grain direction correct  (like it is in the photo above)

OK,  I've got a couple updates here that I'll copy over from the Facebook group.
 
First I'll post up some conversion tips I have learned from those who have built and flown the Yamaha, then I'll post up my (slow) progress in my build.
 
CONVERSION AND TUNING TIPS, Yamaha RX-1 engines
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Airbox considerations:
The snowmobile airbox is large and difficult to fit under a cowl, but when it is used, the RX-1 jetting (135 mains) and setup is fairly close to final tune.
Typically, smaller custom airboxes are made and, generally speaking they tend to run leaner... requiring larger jetting (up to about 180 sized) to achieve the correct air to fuel ratio.
An airbox is generally needed to buffer under cowl turbulence and allow for consistent pressure across the carb rack (RX-1).  Individual filters on the carbs have been reported as highly problematic, especially at higher speeds /  cowl pressures.
Carburetor venting (float bowl) needs to match internal airbox pressure and not the under cowl pressure.  This is typically done by running venting inside the airbox.  (See note below)
Also the crankcase breather is vented into the airbox.
It should be noted that when rerouting the float bowl vent lines into the airbox that you should have a way to allow for fuel overflow to exit the bottom of the airbox.  I have seen a stuck float in sleds where quite a bit of overflow comes out of those vent lines and you would want a way to evacuate that excess from the airbox and route it to a safe exit point.
This airbox exit will also serve as a oil exit if any were to "burp" through the crankcase vent line in the airbox.
I ended up going with an airbox off of the Yamaha R1 motorcylce (same engine block as the RX-1) and will make a seperate post on that.
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Header construction:
I chose a custom header from a pvc mock up kit that I will do another post on below.  (Pic of my mock up below)
Header primary tubes (prior to collector) need to be as long as practical (24"+ ideally) and as equal length as possible.  A 4 to1 collector is common in the R1 motorcycle header, snowmobile exhaust (which is later split to dual exhaust) and aircraft fabrication. 4-2-1 designs have also worked very well.
The primary tube ID on the RX-1 is 1.28 and 1.38 on the R1 (which uses an EXUP type valve in the collector to "choke" at lower rpms).   So there is a 1-3/8 size that is ideally used (It can also be found as a 35mm metric size).  It comes out to a 1.37 OD and about 1.32 ID. 
Keeping proper tube dia, long (and equal) primary length, and smooth inner tube transitions will help throttle response.  If you try to deviate from those things too much your run quality will likely suffer.
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Modding headers from other vehicles: 
Using a pre fabricated header off another vehicle can work well for non-cowled applications.  For planes with a cowl, I found that the rework on any of these options outweighed a full custom fabrication.
Some people have successfully used motorcylce headers such as from the  R-1 motorcycle and  07-08 gsxr 1000.  The motorcycle headers run about $50 on ebay but are sometimes made of titanium, so modifying them can be problematic.
The 1990's Honda Civic headers have identical port spacing and are avail for $60 in steel and stainless steel but the tube diameter is a smidge on the large side which makes the "step up" transition from the snowmo flex flange output a bit problematic and there can be a little bit of throttle lag / hesitation when using tubes that are too large.
Suzuki samurai headers have also been used and line up well with the head, but like the civic header they do not bolt right up, so you have to cut them and weld in a flange adapters.
If I were working with the civic or samurai header I definitely would buy the one piece header flange (with stubs) for the yamaha 4 cyl from GP Headers to save a ton of time and frustration getting these headers matched up to the head.  
www.gpheaders.com
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As far as mufflers, I am using a 2012-14 gsxr 1000 muff
For those of you that  have the yamaha three cylinder you can use the yamaha yxz 1000 side by side header pipe . Same engine nice long sweep headers that curve down.  (See pic below)
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Tuning with the AFR guage:
Some guys here know a ton more about the afr guage than I do, and which one is best to buy.  I'll leave it to them to post up their opinions.  But generally speaking, my notea show that we should be looking for Air to Fuel Ratios of about 18:1 at idle, 13.5 for cruise, and a little richer for WOT.. about 12.5 to 13.0
Teals note:  I have ran a few RX1 aircraft and noticed that a leaner idle (17-19) seems to work really well. I have found that if i set the AFR at 13-14) at idle it will have a little rough spot around 4500-5500 rpm.
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RX-1 Jetting
Ok.  The RX-1 uses altitude compensating Constant Velocity  (CV) carburetors.  I'll let an expert explain how they work via the vacuum slides (yamaha calls them "piston valves") in front of the throttle butterfly, but generally speaking the vacuum slides have a spring that can be changed for tuning purposes, the main jets can be changed or drilled out to enlarge, the needle position (in the vaccum slides) can be raised and lowered, and the idle mixture adjustment made via a fuel screw.
Alternate vacuum slide springs  and main jets are available from Holtzman (Steve Henry's setup uses the blue colored Holtzman slide springs)
NOTE THAT IF YOU CONTACT HOLTZMAN, TELL THEM YOU ARE TUNING A "SNOWMOBILE"!  They don't understand experimental rules and are a little nervous about supplying parts for aero use.
http://www.holtzmaneng.com/carburetion-products
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As far as drilling main jets,  If you have a full drill index you can open your jets up. A 135 main jet is 1.35 mm in diameter or .051"
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Teals note:  These carbs have 3 jets. A idle jet thatvis normally a 17.5 (.175 mm) a main jet  (stock is around 135) and a starter  jet (choke or enficher circuit). The idle jet is used up to about 1/4 throttle then the the needle positioning inside the the needle jet sets mixture. As the slide rises and the needle rises out of the needle jet (needle is tapered so the more it is pulled out the more fuel can pass) the more the main jet controls mixture. The main jet controls mixture mainly at 1/2 throttle and above. More so at 3/4 to wot.  The needles have 5 positions just like most other carbs. Needle position is used for midrange tuning. There is also a screw on the bottom of the carb that sets air fuel ratio at idle and just above idle.  One other thing ive noticed on a number of RX1 carbs ifs that idle jet is opened up. Im not sure if by normal cleaning or drilled. The hole in the idle or pilot jet is tiny at 17.5 (1.75 mm or .007" in diameter). One way to tell is to measure the cleaning wire with a caliper and see how it fits in the jet. Ive found that running these engines with opened up pilot jets causes a slightly rougher transition to the midrange and doesnr idle as smooth. Also this jet doesnt have anything to do with what airbox your using because at what throttle position that these jets are being used at the slides are causing the correct back pressure. Unlike when the slides are opened up at higher throttle settings and there is a lot of air flow through the airbox.
FUEL TYPES:
The Yamaha manuals call for a min octane of 86, and use of fuel with ethanol up to 10%.  That ethanol content may not, however, be suitable in many aircraft fuel systems.
As far as 100LL, the three main concerns are in lead contamination on the valves, O2 sensor (if equipped), and oil.  The screenshots below are  advice from members here about the lead problem, but it should be noted that no problems have been reported in occasional use of 100LL (when that is all that is available) from flyers of the Yamaha.
Consensus here probably being:  If you run avgas (100LL), do so sparingly and remove your O2 sensor when you do.  If you run it more often, use the appropriate oil, plan oil changes more often, and use additives in the fuel that help reduce lead deposits.
Running it exclusively is not advised, but no one has yet found the exact results in doing so.
 

COOLING SYSTEM ROUTING:
Reference the pics below of the cooling system components where each port is labeled. 
(NOTE: Pics are of an RX-1.  As I understand, the APEX should be the same except it would not have C1,C2, or H2 connections.)
The matching connections are listed here:
H2 goes to C1
H1 to 10
X2 to 14
X1 to J
I to the engine block below the headers
H is cold feed from radiator
13 "T's" into that cold radiator line connecing to H (13 is a cold engine bypass route (bypassing radiator) when t-stat is closed, see hand drawn diagram below)
11 is Hot outlet off expansion tank (white tank in my pic) which goes to hot side radiator.
C2 to K
B1 to L
12 is unused, and can either be capped off or drilled out and tapped to 1/8 NPT for a coolant temp sender (note that aluminum is thin for tapping, so take caution if you choose to thread it)




 

CRANKCASE BREATHER:
The crank breather is labeled in the bottom pic here and it  this is connected with a hose to an oil "trap" (top pic) and then typically routed into the airbox, but some people have reported just running it to a negative pressure location (non ram air location) with a filter at the end of the breather hose.
 

OIL SYSTEM ROUTING (RX-1 and APEX):
Reference the three labeled pics of the oil system  (below).  Routing is as follows:
A goes to 1
B runs up and "tees" to both 2 and 4
C goes to 3