You do seem to have too much prop. 56" seems a bit long to me on a KR with a VW, but I have no idea what your gear setup is and how much prop clearance you have. 52-54 is in the more normal range for a VW powered KR.
I would get with the maker of your prop for a recommendation as to what should change if you can get in touch with them and best if they rework the prop if possible. I suppose you could repitch one yourself, but I don't know that most people can do that successfully without experience and the correct templates and pitch measuring tools. I certainly would not attempt it myself. I have cut down my Sterba prop first a half inch per side, then another quarter inch. It is easy to do with a hacksaw and some sandpaper. I spoke to Ed Sterba about sending it back and he said that he could do it, but it is very easy to do and he recommended that I just cut it. He says that as long as the sides are cut relatively evenly that it does not need to be rebalanced, and seems to be fine in my case. Anyway, if your prop clearance is less than what you would like I would go ahead and just cut down a half inch or one inch per side. You should pick up about 50-100 RPM per inch of diameter reduction based on what I have seen from other shortened props, but this depends on your particular prop. Since you will likely not get all the RPM you need with an inch or two of diameter reduction you will more likely need the prop maker to reduce pitch, but I think you will benefit by at least an inch of diameter reduction also. -------- Original Message -------- Subject: KR> kr props From: robert gill <robertgill at live.com.au> List-Post: [email protected] Date: Tue, February 25, 2014 3:32 am To: "krnet at list.krnet.org" <krnet at list.krnet.org> Hi all, does any one have any advise on props, my kr2 has now had its second test flight on it, The prop is a Tonini gt, its a 56*44 and i am only getting 2800 rpm on climb and 2900 at 140 Kts. (160 mph) Revmaster claims full power is 85 hp. @ 3200 rpm. the climb also appears to be lacking. engine is a revmaster R2300. I am missing 3-400 rpm. would trimming down the diameter a little at a time give me back my missing revs.My other thought is, the engine now only has 1.2 hrs on it from new, can the engine develop more power as it runs in, so am i jumping the gun thinking about the prop yet.Test pilot claims the 'little KR' (smurf jet) is a beautiful little plane to fly, well balanced in all controls and, the mod to the tail (same as Troy Petteway's ) has really paid off. not overly sensitive throughout the whole speed envelope and still powerful enough for full control at low speed. (big relief !!).Other thing is i may have ballsed up on my tail incidence as the nose keeps wanting to lower even with full up trim, I added a second adjustable trim to the control bell crank at the elevator with bungee cord to between the seats and that still required a lot of pull to trim the plane out. ortest pilot is also a light weight (he is), I haven't checked the weight and balance figure but I am guessing he has put the CG fwd of the fwd limit. (as a 85 kg (187 lb to you yanks) pilot and full head tank I am 1/4" aft of the fwd limit). I have been told this was to be expected on the first flight (nose down trim that is)One more thing, I have lagging on my header pipes can this cause me to have higher than expected EGT temps approx 50c and higher. (122f for the yanks), lagging was put on to protect wiring and coils, on the R2300 with individual ignition coils, the front exhausts run parallel under the head and approx 1/2" away from the coils. _______________________________________________ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options
