Posted 15 Jul 2016 (edited) I ran into Steve and Yee Haw 5 at the Arlington Airshow in Washington State last week. I spent some time talking with Steve and watched him fly twice. What an airplane! What a performer! That Yamaha is powerful and runs real smooth. It takes a little finesse to start without a clutch but it was a real strong sounding engine. Steve said once he got the bugs worked out he likes it. Two areas he fought were carb venting and exhaust. He said once he vented everything to a common point it worked. He said he changed the exhaust configuration 4 times before he got it to work right. He said it's running very strong now. He said its a stronger runner than his hopped up Rotax. Edited 15 Jul 2016 by rvsimons Share this post Link to post Share on other sites
Posted 15 Jul 2016 Here is a short video I took of Steve's plane starting. I have one of him flying that I'll post once my kid gets home with his phone. My phone went dead. 20160708_113210.mp4 Share this post Link to post Share on other sites
Posted 15 Jul 2016 Got a link to that face book page? I'm not on FB, but my wife is. JImChukIm not a member either, Just type in wild west aircraft Face Book his page will show up and you can view it. Share this post Link to post Share on other sites
Posted 15 Jul 2016 I played it on two devices. Make sure your devices will play mp4 files. My devices were android phones. Share this post Link to post Share on other sites
Posted 15 Jul 2016 Won't play in the Chrome browser, you have to download it, and then if your machine has an mp4 codec it will play directly.Mark Share this post Link to post Share on other sites
Posted 9 Aug 2016 Thanks for the chart, what rpms do you cruise at and what was your max rpm with the c drive.We have the c drive on the engine but haven't started the engine mount yet Share this post Link to post Share on other sites
Posted 9 Aug 2016 Great, a hp conversion table! But for what exactly, a snow machine? Still waiting for some actual RX-1 aircraft application Dyno charts... Share this post Link to post Share on other sites
Posted 9 Aug 2016 dholly,I don't understand your question. This is a dyno run of the engine for any application. It is raw torque and RPM numbers with the engine bolted to a dynometer. what is a "Aircraft application dyno chart" could you possibly be asking for real world numbers as far as airspeeds and rpms for a given airframe with this engine? If so what numbers would you like to see? I have a little bit of data of this engine flying in Steve Henrys Highlander and a number of different trikes and gyocopters. Just in general Steve is able to climb at a steady 1900 fpm from 1000msl. his WOT level flight is 124 MPH with the 3:1 ratio gearbox and slightly faster with the 3.47 ratio. He takes off in less than 100ft. In comparison to the his past big bore 912s with nitrous the stock RX1 pulls harder on a pull scale and pulls harder on takeoff. Static thrust pulls were 580-600 lbs depending on the day. Those pulls were with a 80" X 46" Prince p-tip prop. Both highlanders weighed right at 700 lbs. I hope this info helps but If there are any other aircraft data points that you are looking at, let me know and I may have them. Share this post Link to post Share on other sites
Posted 9 Aug 2016 Those are about the same numbers I'm getting out of my 105 Zipper with a 78x48" Prince in the 700 pound Mangy Fox. Sustained 1700-2000 climb, off the ground in less than 200', wide open speed about 120 mph. The numbers out of the Yamaha are exciting to see. With some more tweaking that will become a very viable engine. I hope the availability of engine cores can be sustained. Share this post Link to post Share on other sites
Posted 2 Sep 2016 I use the ceramic top pistons . They expand at a far slower rate than Non ceramic top pistons . The steel cylinder liner takes several minutes to expand. The colder the tempeture the longer it takes. I recommend 2 minutes at 2200 rpm while taxi to the run up area. Then at 4,000 rpm for 2 minutes. Then increase to 4500 rpm's for 2 more minutes. Then to 5000 rpm for the last 1 minute of your run up. Now do your mag check & your fuel pump test. Do not return to a idle if the take off is delayed by a landing Aircraft. Once on the runway use full throttle until airborne. If your clear of obstacles back the rpm down 250 rpm or more. ( 90% of engines that fail the damage that caused the failure happened while running at full powerYou have only .003 piston to cylinder clearance. If you scuff a piston ( and maybe not even knew that you did ) and your cruising along 10 hours latter at 5,200 rpm and the engine shuts down without know warning at all !!!! EVERY GAUGE WAS READING PERFECT !!! Once you scuff a piston please change it. If not it will do it again 100% for sure. 3 out of every 5 582's that fail is the lower rod bearing. The second largest 582 failure is cold seizures. It's not the engine's fault !! WARM THEM UP PLEASE !!!I have never had a single 670 seize & that's out of 250 + 670's that I have built. .005 to.006 piston to cylinder clearance is the reason.Every 582 or 670 I rebuild get ceramic top pistons. 1 person likes this Share this post Link to post Share on other sites
Posted 10 Sep 2016 Teal or Marshawk, any progress on the conversions ? Share this post Link to post Share on other sites
Posted 11 Sep 2016 I have the adapter plate and c drive on the engine but haven't started the motor mounts yet ,time is never on my side but hopefully in the next couple weeks will have some time to built it, then comes all the wiring and plumbing etc Share this post Link to post Share on other sites
Posted 18 Sep 2016 Anyone doing this swap should definitely create a build thread.Electronics, plumbing etc will be very valuable info.Saw a youtube video about a gyro running this engine. His digital speedo in the Yamaha cluster worked .Is that common ? 1 person likes this Share this post Link to post Share on other sites
Posted 19 Sep 2016 This is Steve Henrys engine install. He has a littlw over 60 hours on it. He reports it has as much power as a big bore 912 with a turbo. He recently installed the rk400 clutch and seems to be working good for him. Share this post Link to post Share on other sites
Posted 20 Sep 2016 Any progress on Terry's plane? I will be following that closely. Share this post Link to post Share on other sites
Posted 20 Sep 2016 Yes, The RX-1 is temporally mounted and the new engine mount is almost done for Terry's Avid but Terry is having a bunch of things done to his so it might be down a little while. Share this post Link to post Share on other sites
Posted 22 Sep 2016 Any chance you are going Prescott for the AOPA fly in next weekend? Wife and I flying down to meet an old Airforce buddy of mine and Terry for the weekend. Share this post Link to post Share on other sites
Posted 30 Sep 2016 That thing is going to be like a helicopter. Cant wait to see that fly. Be sure to post performance videos. Share this post Link to post Share on other sites
Posted 7 Oct 2016 I can't say I am on the edge of my seat following this engine choice, but I do follow it with interest as it finds it's way into tube and fabric aircraft. I hope it works out and appreciate MohawkAero (how about a 'proper' name?) joining the forum and contributing to the thread. IMHO, all information now and in the future is welcome in my eyes. Share this post Link to post Share on other sites
Posted 7 Oct 2016 Greg mills, some of your information here is not true. I do appreciate you sharing some personal experience with the engine as it may be helpful to others. You kind of make me out like a copy cat and i dont appreciate it. Early on when i first started hearing about the yamaha snowmobile engine i did in fact inquire to you about your adapter kit and after i found out you were using the stock cover with a chain drive bolted on top of it I wasnt interested and came up with my own that completely replaces the stock cover and bolts a gearbox directly to the engine and my intentions were not to mass produce these or even make another but my friends wanted some so i got the cnc program and now i can make them as needed but i in no way have a business doing this as you. After i came up with a good adapter with some reputation you in fact inquired to me about buying my adapters if i would modify them to accept your chain drives and i told you i wouldnt do that. Over last couple years i have been watching to see if you have completed kit ready to sell and not just acepting deposits. Are you now actually shiping out kits? Because some people on here might be interested in the chain since it brings the prop closer to the top of the engine where it could be easier cowled. I know I sold a adapter kit to Steve Henry of wild west aircraft and he told me he gave you deposit of $1500 for one and that you were still in development but that was about a year ago. Did you get steve out one yet? It would be interesting to see how it works in the highlander. He is currently flying with Skytrax adapter. Share this post Link to post Share on other sites
Posted 7 Oct 2016 Greg, thanks for posting im sure everyone loves the pics and the info. I cant wait to see steve's apex engine adapter he gets from you. Heck i might buy one from you if steves works out. i dont currently have plans to build one for the apex engine if your works good. Share this post Link to post Share on other sites