I changed out the 3/4 inch spring bar and installed a 1 inch spring bar on my kr2 after hearing about the hard landings putting the wheels up through the top of the wings on some other KRs with retracts.
My kr2 is actually a 1.5 bird since I made it a single seat version due to the gross weight being 1070# that includes me and 18.8 gallons of fuel. Keep in mind my bird has a VW 1835 with an A-Jay turbo charger, electrical system, transponder and geared starter motor. I also modified the gear lock system to use a 1/2 inch locking pin through a semi circle arch of steel that mounts to the center section hinge and the floor. This pin is spring loaded to lock in place in the up and down position and is retracted via a jet ski steering cable and has an emergency hand hold to operate if the cable breaks. I have not flown my bird for almost 19 years due to health problems (diabetes) which I am getting over having to use insulin and so should be able to pass my physical here shortly. I have been modifying several things on the plane getting it ready to fly again. I am currently building an aluminum seat and I changed the position of the vertical stabilizer spar to eliminate the need for rudder trim, I was having to hold some left rudder to center the ball prior to this. I also relocated the battery to the firewall, it was behind the seat before, and I moved the oil cooler from the top of the engine to the bottom and gave it its own NACA scoop for cooling air. When I get everything back together and ready to fly I am hoping that I was able to lower the empty weight some and have a more forward CG for better control of pitch sensitivity. I have approximately 250 hours on my bird so far and it is a lot of fun to fly. I have flown it to Edwards AFB for their airshow a number of years ago and also to Wendover Nevada and several local airshows here in the west. Oh, one other modification I am thinking about doing is to have the one inch spring bar machined down so that it tappers on the outer ends to reduce some of the weight without compromising the stiffness to much. I also designed my own fuel flow gauge which uses no moving parts, it is a capacitive type fuel gauge and is very accurate, it uses a capacitive baffle plate inside the fiberglass tank and is accurate within 1/2 gallon in all attitudes. Hope this information helps. Parley Byington N54PB KR-2 (1.5) Henderson Nevada byington1...@embarqmail.com > On Jan 14, 2019, at 16:28, Flesner via KRnet <krnet@list.krnet.org> wrote: > > On 1/14/2019 1:11 PM, Kevin Stolhammer via KRnet wrote: >> That may >> make it worth the expense.Certainly you work have to get some super >> performance increase to make it cost effective. > > +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > > If you're factoring in cost, don't forget to account for the cost of a $400 > propeller and engine tear down the first time the gear collapses. The > retracts on the KR were quite a novel idea when Ken build his 480 pound KR2 > but no one builds 480 pound KR's now days and haven't done so for the last 30 > years. 650 pounds is more representative of a "light" KR today with many > coming in at 700+ and several most recent I'm aware of are 800+. If a hard > landing in a 500 pound KR will put the gear bar through the top wing surface > imagine what a 2 G landing in an 800 pounder would do. (can you say "instant > wing spoilers") If you're building a "light" KR and want to go retract there > is no reason not to. Just be aware of the short comings of the original > retracts and try to eliminate any of their problems, as several builders have > attempted to do. Some have tried modified lock downs, some have shortened > the bar to stiffen it, etc.,etc., ........... > > Like I've said many times, go with what you're comfortable with and accept > the consequences. > > Larry Flesner (29 years of KR exposure - 15 years flying one) > > > _______________________________________________ > Search the KRnet Archives at > https://www.mail-archive.com/krnet@list.krnet.org/. > Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options. > To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org _______________________________________________ Search the KRnet Archives at https://www.mail-archive.com/krnet@list.krnet.org/. Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options. To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org
