---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Tue 12/14/10: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:19 AM - 2010 List of Contributors (Matt Dralle) 2. 02:40 AM - Re: Losing rpm on takeoff (Dave G) 3. 06:14 AM - Re: Losing rpm on takeoff (Roger Lee) 4. 06:49 AM - Re: Re: Rotax E-Learning video on detonation and pre-ignition (Noel Loveys) 5. 06:55 AM - Re: Losing rpm on takeoff (lucien) 6. 09:53 AM - Re: Rough Running 912 (moosepileit) 7. 10:29 AM - Re: Rough Running 912 (Roger Lee) 8. 03:54 PM - Re: Re: Rough Running 912 (Ken Ryan) 9. 04:14 PM - Re: Rough Running 912 (lucien) 10. 06:30 PM - Re: Rough Running 912 (Roger Lee) ________________________________ Message 1 _____________________________________ Time: 12:19:21 AM PST US From: Matt Dralle Subject: RotaxEngines-List: 2010 List of Contributors Dear Listers, The 2010 Matronics Email List and Forum Fund Raiser officially ended a couple of weeks ago and its time that I publish this year's List of Contributors. Its the people on this list that directly make the Email Lists and Forums possible. Their generous contributions keep the servers and Internet connection up and running. You can still show your support this year and pick up a great gift at the same time. The Contribution Web Site is fast, easy, and secure: http://www.matronics.com/contribution Or, by dropping a personal check in the mail to: Matt Dralle / Matronics 581 Jeannie Way Livermore CA 94550 I also want to thank Bob, Jon, and Andy for their generous support through the supply of great gifts this year!! These guys have some great products and I encourage you to visit their respective web sites: Bob Nucklolls - AeroElectric - www.aeroelectric.com Jon Croke - HomebuiltHELP - www.homebuilthelp.com Andy Gold - The Builder's Bookstore - www.buildersbooks.com And finally, I'm proud to present The 2010 Fund Raiser List of Contributors: http://www.matronics.com/loc/2010.html Thanks again to everyone that made a Contribution this year!! Matt Dralle Matronics Email List and Forum Administrator ________________________________ Message 2 _____________________________________ Time: 02:40:19 AM PST US From: "Dave G" Subject: Re: RotaxEngines-List: Losing rpm on takeoff Problem solved, although what is actually happening is a subject of some debate. Those who operate the Warp drive taper tip props or have experience with them were exactly right and ignoring static RPM was clearly the way to go. I ended up with a very nice smoooth prop after reducing pitch significantly. It is now pitched to allow 6200 rpm in full throttle climb at 0 deg temp. I expect we will have to revisit this when it warms up. The engine will overspeed quite easily on the ground until speed builds. I have spoken to a few others with the same type of prop and their expereince is similar. Thanks to those who offered asistance, it would have taken somewhat longer to get it right without it. ________________________________ Message 3 _____________________________________ Time: 06:14:19 AM PST US Subject: RotaxEngines-List: Re: Losing rpm on takeoff From: "Roger Lee" Hi Occom, I have lots of people ask me what static rpm to set. My standard answer is; the static is only a place to start when putting on a new prop and you have no real idea of an exact pitch and final rpm. I always tell them set a general static rpm and go fly. Flying is the only way to be exact and sure of the final results. This is the only way to dial in a prop/engine rpm to match your plane and local flying conditions. -------- Roger Lee Tucson, Az. Light Sport Repairman - Maintenance Rated Rotax Repair Center Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=323340#323340 ________________________________ Message 4 _____________________________________ Time: 06:49:11 AM PST US From: "Noel Loveys" Subject: RE: RotaxEngines-List: Re: Rotax E-Learning video on detonation and pre-ignition Any Ideas about the neighbourhood of the AOA for that? Noel -----Original Message----- From: owner-rotaxengines-list-server@matronics.com [mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of Dave Austin Sent: December 12, 2010 11:52 AM Subject: Re: RotaxEngines-List: Re: Rotax E-Learning video on detonation and pre-ignition I'd be a bit concerned that with prop set to 5300 static that it could easily over-rev on climbout. I use 5000 static. Dave ________________________________ Message 5 _____________________________________ Time: 06:55:33 AM PST US Subject: RotaxEngines-List: Re: Losing rpm on takeoff From: "lucien" [quote="occom"]Problem solved, although what is actually happening is a subject of some debate. Those who operate the Warp drive taper tip props or have experience with them were exactly right and ignoring static RPM was clearly the way to go. I ended up with a very nice smoooth prop after reducing pitch significantly. It is now pitched to allow 6200 rpm in full throttle climb at 0 deg temp. I expect we will have to revisit this when it warms up. The engine will overspeed quite easily on the ground until speed builds. I have spoken to a few others with the same type of prop and their expereince is similar. Thanks to those who offered asistance, it would have taken somewhat longer to get it right without it. > [b] That sounds pretty close to me. On my Kolb/503, I got about 6300 on a normal climbout (tho I don't actually remember that speed offhand), tho that was slightly underpropped for WOT at straight and level IIRC. But like I said, tho I love my powerfin, I wish I could make my 68" taper tip work on my tornado. Once I had the pitch dialed in I was able to do 100mph indicated (about 110mph true) at only half throttle at 10,000' MSL. Plus, I could get a virtually constant 5400rpm on climbout even varying between 65 and 80mph indicated. The static rpm always seemed to settle at about 5200 rpm no matter what the pitch was set at (I went from 13.5 to about 15 degs in the course of the dialing in and the static was always the same)..... LS -------- LS Titan II SS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=323342#323342 ________________________________ Message 6 _____________________________________ Time: 09:53:28 AM PST US Subject: RotaxEngines-List: Re: Rough Running 912 From: "moosepileit" My Kitfox w/ 912 UL 80 hp came from a 5000' MSL field and is now hangared at sea level. It was rough from around 4000 to 3700 rpm on a digital tach. and has 2 egts running @ 1400 degrees. Carb needles were up at position 2. Makes sense for where the plane used to live. Dropped the clip to normal positions 3, raising the needle and the egts are the same, but now smooth running all rpms. (Thanks, Roger!) I thought it might take dropping to clip position 4 to fully raise the needle or a change of needle and jet from standard as it's now mid 30's when I fly, but the position 3 did it for me. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=323361#323361 ________________________________ Message 7 _____________________________________ Time: 10:29:37 AM PST US Subject: RotaxEngines-List: Re: Rough Running 912 From: "Roger Lee" Position 3 on the carb needle is normal and a good place to be for the majority of us. If you live and fly from high elevations then maybe #2, but be ware if you come down to visit us low landers. #3 is good for most during summer and winter. The more you tinker against what Rotax advises the more chance of making a costly error or a poor running engine. You need to be able to fully understand the Rotax engine and how to accurately interpret engine information on the gauges or test equipment. If you don't then leave it as the factory set it up and you will fly to your TBO without any issues. -------- Roger Lee Tucson, Az. Light Sport Repairman - Maintenance Rated Rotax Repair Center Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=323365#323365 ________________________________ Message 8 _____________________________________ Time: 03:54:21 PM PST US Subject: Re: RotaxEngines-List: Re: Rough Running 912 From: Ken Ryan So all of this talk of changing needle positions based on altitude has me wondering. What if you want to fly from sea-level to high altitude? What then??? Ken Ryan Anchorage, Alaska On Tue, Dec 14, 2010 at 12:26 PM, Roger Lee wrote: > > Position 3 on the carb needle is normal and a good place to be for the > majority of us. If you live and fly from high elevations then maybe #2, but > be ware if you come down to visit us low landers. > #3 is good for most during summer and winter. The more you tinker against > what Rotax advises the more chance of making a costly error or a poor > running engine. You need to be able to fully understand the Rotax engine and > how to accurately interpret engine information on the gauges or test > equipment. If you don't then leave it as the factory set it up and you will > fly to your TBO without any issues. > > -------- > Roger Lee > Tucson, Az. > Light Sport Repairman - Maintenance Rated > Rotax Repair Center > Home 520-574-1080 TRY HOME FIRST > Cell 520-349-7056 > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=323365#323365 > > ________________________________ Message 9 _____________________________________ Time: 04:14:13 PM PST US Subject: RotaxEngines-List: Re: Rough Running 912 From: "lucien" kenryan wrote: > So all of this talk of changing needle positions based on altitude has me wondering. What if you want to fly from sea-level to high altitude? What then??? > > Ken Ryan > Anchorage, Alaska > You shouldn't have to change anything. I live at 7000' MSL (northern NM) and fly usually up to 9999' MSL, even on local messing-around flights. My carbs still have the factory jetting and they compensate fairly well. Mine run a bit rich at low power settings (i.e. between 2000 and 3000 or so on the ground or during approaches) and it's going to idle rich also (if you use the factory 1.5 turns on the idle needle). But at full power it still leans out fairly well, giving EGT's in the 1250 to 1350F range. So shouldn't be a problem... LS -------- LS Titan II SS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=323383#323383 ________________________________ Message 10 ____________________________________ Time: 06:30:06 PM PST US Subject: RotaxEngines-List: Re: Rough Running 912 From: "Roger Lee" I'm with Lucien. leave it alone. You will be a little rich for that flight, but so what it will fly just fine. Making a permanent needle adjustment should mean you are more or less permanently at altitude. -------- Roger Lee Tucson, Az. Light Sport Repairman - Maintenance Rated Rotax Repair Center Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=323400#323400 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rotaxengines-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RotaxEngines-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rotaxengines-list Browse Digests http://www.matronics.com/digest/rotaxengines-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.