Yamma-Fox

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Posts posted by Yamma-Fox

  3. Posted

    Superman talkin here...

    It's never supermans fault.   

    Rigging was off

    Brake musta hung up

    Caught a bit of a wake from the Magnum that preceeded me

    Had an albino deer run in front of me and those things are endangered... had to put it in a loop to save him.

    Superman has a pocket full of these all cued up in his mind ahead of time!

     

    2 people like this

  6. Posted

    RX1 / Apex engine mount for Avid:

    (For anyone who may of missed it in the general hangar)

  7. Posted · Edited by MN Kitfox 2

    Thanks so much for offering this service!  

    The mount, header, and airbox are the three obstacles to the conversion that are a bit beyond my fabricating capability.

    A little help in those areas will be great for those of us who dont posses those "pioneering abilities"  :)

  8. Posted

     

    Depending upon weight, would love to have 120 HP in an Avid/Kitfox

    As for ignition and needed reliability, that's a tough one.  I'm guessing the ignition is synchronized with the turbo operations.

    It sure would be great to see the sidewinder adapted!  So far it appears no one has approached it though.

    It would really open up a huge market in the EAB community (far beyond the rotax niche) since some simple tweaks can put the motor up to 250 HP

    http://mcxpressturbos.com/turbo-kits/snowmobile/yamaha/sidewinder/

    But if  about 120 HP is what you want, then I think the RX1 motor seems like the way to go.  Simple, proven (to at least some degree), cheaper, and with conversions available.

  9. Posted · Edited by MN Kitfox 2

    Yeah flutter SUCKS!   Been there... done that!

    The faperons on my old kitfox 2 had what seemed to be a minor amount of play.  Out flying and encountered pretty bad flutter... not a good deal, was lucky to get back to the field.

    So get the slack and play out as best you can.

    And a lesson learned for my experience:  if you ever get flutter in flight, change something quick.  Like slow it up and stall it if you have to, or add some load (and take away slack) on both flaperons by putting in some flaps.  Whatever, but don’t continue flying around in a flutter like I did!!

     

    2 people like this

  10. Posted

    I agree that the soob must have more torque,the gear ratio was 2.53/1  and the yamaha is roughly 3.5/1 with the built in reduction, the soob swung the prop at 11 degrees 4800 rpm and the yamaha is now at 8 degrees(at the prop tip) and were getting 9000 rpm wot, we are still messing with the main jets to make it happy, its a bit of a pain to get main jets for the mikuni carbs  , I guess everything is going fuel injected these days. My cruise is 6500 rpm and think it was around the 80 mph in the RX1

    Anxiously awaiting your final results once you get the Yamaha tuned and dialed in!

    An avid going from a Suby to a Yammy with the same prop...  the best "apples to apples" data that can be had!

    Taking a wild guess here, but once you get tuned, and set up for a  prop pitch that puts you somewhere in the middle of the power prop / cruise prop compromise, I bet you will be back close to 11 deg.

    And 2 cents worth of ideas on tuning:  my float level was off and my rx1 was running so rich that it was only putting out power equal to another sled I own that is 90 hp.  Slight float adjustment and the rx1 was faster than my 135 hp ski doo 1200.  Point here being that the float level plays a major role in mixture.  Also, I  sure like the O2 sensor (fuel to air ratio) guage that teal uses.  That is the way a lot of turbo snowmo users guage their tuning and I kinda think it gives better data even than egt does.

    1 person likes this

  11. Posted

    Attached an engine today.

    20170412_165116.jpg

    But back to topic:  Congrats!  Can't wait till I can take a pic like that!  Those headers look like a work of art.  Did you make them?

  12. Posted · Edited by MN Kitfox 2

    And experts help my thinking here, but the 6 deg willis was shooting for was on the warp protractor...  near the tip right?  So i think that doesn't quite equate to say a hartzell pitch at what is it like 70% of prop length.

    Point being that maybe 6 deg is not so flat as it sounds?

     

  14. Posted · Edited by MN Kitfox 2

    Yeah,  Greg knows of the trike guys who have adapted the 3cyl nytro motor.  Think he makes an adapter.  But only one FW guy that I have heard of (in Norway) who has done it.

    Like the Apex efi, you'd obviously have some hoops to jump through with regard to the harness and limp mode overrides.

  15. Posted

    As far as jetting, i know steve henry would be a good resource.

    Personally I like teal's use of the O2 sensor to guage air/fuel ratio.

    But for a quick check to see how it is performing, I think I would start with a simple thrust pull check once you get it pitched for rpm.  People with experience chime in, but as I understand, a well tuned and healthy  rx1 should pull a bit over 500 lbs.

    1 person likes this

  16. Posted · Edited by MN Kitfox 2

    Thanks much Vance!

    Posting all that you have on the Facebook site is a big job in itself!  I'll try and put a link to the Facebook group (created and administered by Greg Mills of Mohawk Aero) so anyone here who is interested can join up over there.

    That may help so you don't have to double post everything!

    https://m.facebook.com/groups/1251356951570824?ref=bookmarks

    Brett (aka "Anatoli" as my Facebook alias)

     

  17. Posted · Edited by MN Kitfox 2

    I like the clean install of the  polaris razor radiator that teal has done!  Pic below is all I have.  It mounts to bottom of engine mount and does not penetrate out the cowl or into the airstream, rather it is flush with the cowl and presumably  gets flow (downflow) pushing through the cowl openings near the prop.  Maybe he can post how well it is working down in the AZ climate.

    And i personally plan to use the rx1 oil tank because it incorporates the low oil warning and it is designed specifically for the rx1 (albiet a bit ugly)

    20170121_165300.jpg

  18. Posted · Edited by MN Kitfox 2

    Reference for my last post.  I think this chart was posted earlier?  (I stole it from someone...)  ;)

    RX-1_CPR_Dyno.thumb.jpg.2dccc61b1ebbd13378c0da21f622f623.jpg

  19. Posted · Edited by MN Kitfox 2

    Teal or anyone ,on the RX1 with wide open throttle and with the plane tied down im getting 8000 rpm with a 72 inch 3 blade warp drive,is this in the ball park of having the right pitch? Just looking for a starting reference for the first flight

    Getting close to flying!   Congrats!!

    Sounds like the same prop I was planning.  I forget, are you using a clutch?

    And I'm sure you figured for it, but I did run into a limp mode (6000 rpm max) on my RX1 on the snow when the overheat light came on.  I think Greg Mills uses a certain resistor in place of the temp sender to trick the ecu into believing a normal temp value.  But my sled seemed to run fine by simply unplugging the temp wire at the sender.  With it unplugged I can't see how you would encounter a limp... right?

    Keep us posted Willis!

    And FYI for anyone... the RX1 snowmobile hits 10,200 rpm (142 HP) every full throttle application.  And Teals reccomendation for 8500 would result in a PTO output shaft rpm of about 7200 (with the 1.19 engine internal reduction) @ approx 127 HP.  Point being that 8500 sounds like a lot... but it really is a pretty big derate.

     

  21. Posted

    I heard that California power systems may have a service bulletin explaining the tolerances and shim requirements.

    I have a new cbox and wanted to spec out this as well, but have it lower on the to do list right now :wacko:

    If ya find some info, please post!

  22. Posted

    Thought I would post a picture of the throttle setup we came up with to use the RX1 throttle cable with the existing throttle cable I had in the plane ,it works well.Got a few more weeks before its flying but its running awesome

    IMG_1434.JPG

    Cool!

     I was wondering how that was done.  So I assume that this is a mod on a 2 stroke throttle mechanism?  

    Can you send measurements (from pivot to the yam cable and to the cockpit pushrod).

    Also, how much travel do you have on the cockpit throttle control.

    Thanks!

  23. Posted

    Finally got around to tearing down the gearbox/clutch.  A large chunk of lining had come off and was causing the drag and squealing.  Given the problems started suddenly in the cold, without having run or touched the engine, I think that some moisture was trapped under the lining and broke it off during the cold.

    Clutch overhaul kits seem to be on backorder everywhere... Grrr.

    Jim

     

     

    Curious, how many hours were on that clutch before it failed?

    And BTW, I saw a guy had one listed for sale here recently:

    http://www.avidfoxflyers.com/index.php?/topic/4832-excellent-shape-rk-400-clutch-for-c-box/

  24. Posted

    A big thanks to Teal for taking a few hours of his time to show me around his shop and hangars!

    Great to see (and hear!) the Yamaha in various stages of conversion.

    I still need to get my rx1 tuned up a bit and running to full power in the sled, then hope to get to the job of pulling it and getting it in the airplane.

    Thanks again Teal!

    1 person likes this

  25. Posted · Edited by MN Kitfox 2

    In MN I always keep a hairdryer or propane heater handy for all my dang machines!

    But a temporoary drop below 30 degrees  doesn't sound cold enough to freeze it up... 

    Hope it turns out ok.

    Please post back with what you find  (I am also planning to use the clutch here in cold weather)