Raptor 50 titan with 620 blades and hyper 50

[sfhawk]

I have a raptor 50 titan with an OS hyper 50 on kit gearing but with the 620 cf blade option. After mostly practicing on my 450 se v2 i found it quiet easy to bog down the engine despite my limited flying ability and also running a governor! I suspect my setup is good and that the option lower ratio is the answer to my problems without going silly with the head spead. Anyone else had the same experience? I went for the big blades for the stability but i find the wind catches that big rotor disc worse than my 450 se v2! I wouldnt have believed it unless i'd done it. Can this be right or does my raptor need more setting up? Bearing in mind that i also set up my 450 and its great!....? I think those big blades are overwhelming the heli's momentum and somehow it just looks way out of trim in a hover compared to my little 450....

[LAMAR COOLEY]

sfhawk,
What are your pitch settings ?
What is your head speed ?
Regards

[sfhawk]

Hey Lamar. I fly 0 deg at mid stick and a plus 5.5 deg at 66 percent and plus 11 deg at full pitch. I set the headspead up with a governor so that i get a hover out of ground effect at 66 percent stick. It just doesn't sound like the engines pulling many revs and it certainly doesn,t take too much to lose some headspead despite running a governor. If i up the headspead much on what i'm running i start to get a vibration so that just leaves me thinking that its out of its rev range due to both the extra load and lift from the 620s. ie mechanicaly the engine will be running slower and with more load to make the same lift!
Your thoughts?

[sfhawk]

Hey people help me out! I think i have it worked out and just need to fit the option gearing ie lower ratio to swing the 620 blades but it would be nice to get a second opinion! Preferably from some one whos had a similar problem...

[bigdwalker]

I use 620 mm blades on the 8.72 ratio, it means that the engine is producing peak power at around 1950 rpm on the head so if you run 1975 you are just above it and thus when you bog the heli it falls into its peak power band. I run the sabs but I did find for real power hungry 3d stuff on 20% it did struggle a bit on 30 its great but if your just sport flying there is no need and you will notice a difference on the 8.72

[sfhawk]

Thanks Bigdwalker. Thought i had worked it through sensibly but its always better to hear someone else has been through it! Now from my 1/8 rallyx days i also suspect that the kit thunder tiger pipe is strangling my OS50 Hyper-sounds flat rich or lean! I know OS engines are good and i have it setup good so do you have any recomendations on an upgrade pipe? Is it worth doing? I had considered the align one as a fellow flyer is 3d ing with one succesfully..

[sfhawk]

OOps just noticed you fly with an MP2 on your OS.. Thanks, i'll maybe give one a try.

[bigdwalker]

I bought a MP2 just before the MP5 was released and I did notice a good increase in power, it is a bit noisier than a MP5 that others are using at my club however its not nearly as loud as an align pipe which really is loud and only slightly cheaper than a MP5, however at the weekend I did get to see bobby watts flying the new ma 50 with an hatori which was very quiet with great power.