I went to look at it with akflyerbob.. He is the one that has to have at least 4 airplane projects going at one time all the time. the sad truth is that's no shit.. I think being retired he has to build and sniff poly tone to keep him young.
I contacted GNS about their engines almost a year ago, Once he found out I was considering it for an airplane he hung up. I called him back and he explained he wants nothing to do with airplanes, doesn't want the liability. He is a pilot himself. He clammed up about even talking about it once he knew it was for a plane. Too bad, he has a lot of knowledge about the Yamaha engines and would be a good resource. Yes, he pumps those Yamaha motors up to some incredible HP for sure.
Reference post above, here is Thomas H's (Edge Performance) comments on the project: It’s Yamaha time. I’ll try and keep this post alive as we progress. Step one is to tear down the engine and inspect and measure the internals. Ultrasonic clean and bead blast all parts. Send off all steel parts for tumbling and cadmium/zinc plating. Next, install forged pistons and rods, new bearings, ARP studs and MLS head gasket. Make a mil-spec Raychem DR-25 motorsport harness and adapt the Apex engine to our ECU. Make a 4-into-1, S321 turbo manifold and fit a Garrett turbo. Thinking either GT2860R or GT3071R. We’ll see how bald we dare to be. Fit Teal’s Sky-Trax PSRU Run it like we stole it on the test bench and dyno. Gain data and numbers. * Maybe do a full head job with full radius cut valve seats, grind the valves, and possibly a 5-axis CNC porting job. Needed, NO! Would it be cool, YES !
Due an update here. Teal has made a few upgrades to the original design, to include a larger oil reservoir, an oil level sight guage, and helical gears. And bigger news (for anyone that has missed it) is that Edge Performance is working with Teal on a full zero timed Apex with beefed up internals and their fully automated aviation grade Turbo. Edge should be testing a prototype here within the next two months and Steve Henry is planning to be the launch customer. HP in testing will be in the 250-300 range. Production units are planned to go out in a detuned range of 180-230 or so. For reference, the Apex is run up to 600 HP in the snowmobile drag racing world. Basically, Edge is planning to do all the internal upgrades (as seen in the pic below and website link) that are used for the 600 HP race sleds, but send it out to only run it in the 180-230 range for aircraft use. http://www.powerbygns.com/Products.html Follow the Edge Performance build in the FB post here (click the "veiw on facebook" link)
I would definetly have it looked at, that way u know and there probably nothing wrong with itnbut the end seals should b changed and check/replace the waterpump seals, i had mine looked at by Darby's Performance Machine here in Fairbanks, mine was all good inside so no parts to replace was just a gasket,seal,and a mag check on crank for cracks, im sure is more to the checkout of motor, was only $380. Make sure its ur "Airboat Motor" lol. They r ski-doo/Rotax guys there with lots of parts instock.
Can't wait for the flight reports mr! I think with the thrust line issue fixed and the lighter weight it should be a completely different bird! I am still shaking my head over the down thrust they had built into the subie mount.
Aeropoxy seems to be the best epoxy for fuel tanks. I have Cozy plans, and hang out on the Cozy forum as well. All reports of Aeropoxy used in the fuel tanks are positive. On user did a coupon test with various epoxies. Most worked fine, but Aeropoxy held up a year in a bottle of E-85. Mark
These are good points, Chris and I don't doubt your experience. Damping and mass of the wheel itself are certainly factors to consider. However, every single time I have encountered tail wheel shimmy on my plane and others, it was directly caused by (and solved by) adjusting the caster angle of the pivot axis. My plane was shimmying badly during my trip out west. The steel spring had sagged and was making for a negative caster angle. On that trip I purchased a used Grove aluminum spring. After installing the spring, all shimmy went away and as you can see, it has a positive caster angle. During the spring installation I disassembled the entire assembly to check for wear and anything else I could find. All was good and the swivel action is very free and loose. The chains also have some slack in them. No shimmy at all.
I cant believe my luck!! I found the exact part I was going to buy pieces to make. Just under $20 a piece but I would have just as much or more into them if I had to buy and fabricate them myself. This company also sells other items for small heater systems. The company (UPI) sells Recreational Vehicle (Side by Side) heater and radiator supplies.
I am replacing my King Ky97 for a dual frequency garmin SL-40. The King comes with it's tray and is in good working condition. I can include a com whip antennae if someone needs it. It's all yours for 590 $ + shipping
I do not know the construction of this particular tailwheel, but in order to increase resistive damping something has to be tightened. If it is possible to replace flat washers with belleville washers, that would be a great way to make the desired amount of resistive damping consistent over time.
This is a post I made on another topic about tailwheel shimmy. I was too lazy to try and remember exactly what I posted so here is a copy and past. I spent a lot of time chasing TW shimmy. I have found tailwheel shimmy to come from two sources 1) larger tail wheels whose mass moves resonant frequency down to where it can be excited and 2) once in that situation, inadequate resistive damping in the back and forth movement of the wheel. Anything else you do whether it be changing catsor angle, tire pressure, asymmetrical springs, stiffer springs, looser springs, more tailwheel weight, less tailwheel weight....anything, only moves the resonant frequency around a bit and the system still can/will shimmy under the right conditions. Adequate resistive damping is the only truly effective means to eliminate tailwheel shimmy from my experience...which along with $4.75 will buy you coffee at Starbucks!
Possible vapor lock??? I had over 2400 hours behind a grey head 582. No issues. I drive a Jabiru 2200 now and like the simplicity. It weighs the same as the 582 I removed from my Avid when changing to the 4 stroke. John M
If it's never been gone through, then that engine is about 30 years old. Even if it doesn't have any corrosion in it, the assembly lube Rotax used will be dry and gummy by now. Went through that recently myself. I would definatly have it gone through and get it inspected and have new seals and gaskets put in. And if there is any corrosion on the bearings, you will have saved yourself an engine out for two reasons. JImChuk
I flew that tail spring in the picture for over 500 hrs, and lots of bad, bouncy landings. I did break it last spring though. If you get some that's only 1/4" thick, I would for sure go double. This one was 5/16 or 3/8" thick. JImChuk
I really need to learn the lesson to not overthink things too much and just go ahead and do something. I spent a week and a half wondering what the best way to temporarily join the 2 halves back together so i could lay up the joiner strip and originally was going to use popsicle sticks with dabs of bondo but that stuff takes too long to set and i finally realized that hot glue and foam had worked well since i started the project and it worked just fine again. I'm going with the 2 piece cowl. Right now the slight inconvenience of very slightly limited access is far outweighed by ease of construction and however many ounces of weight i'll save.