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215 chief
11-06-2005, 02:15 PM
After spending $600 for new batteries (not the problem)I sent my Hacker B16xl and 44 amp controler back only to find out that this motor was sized marginally. The rotor had started to demagnitize causing the controller to get hot and shut down. So now with a new 77 amp controller and a Hacker C 5012xl I think I have a problem. 8 T piniom and 95 t main gear. According to FXA's rotor speed calc. the new rotor speed is 2950 no load about 1100 rpms to high and about 660 faster than the builders setup. (not me this is my first and boy has it been expensive) My question is can I adjust the th curve to only be at 66% at full to keep the speed down or will this cause damage to the motor because it is not spinning fast enough.

Thanks
Brian

zappedalaskan
11-06-2005, 10:38 PM
Hi Brian,
You might try a smaller (if possible) pinion gear to bring your headspeed down, or go to a 120 tooth main gear. Not sure what Heli your working on..
Regards,
Jay

215 chief
11-07-2005, 10:09 PM
Jay I have a raptor 50 V2

zappedalaskan
11-07-2005, 10:50 PM
Chief,
I know a guy with the same set up. I will email him and get his gearing. I will post asap.
Jay

zappedalaskan
11-08-2005, 01:50 AM
Chief,
I was way off.. The proper gearing is 85 tooth main (stock) and 10 tooth pinion. your at 95t main and 8t pinion. I am still checking this out.. I am curious.. to the calc sheets!
Jay

zappedalaskan
11-08-2005, 10:44 AM
After spending $600 for new batteries (not the problem)I sent my Hacker B16xl and 44 amp controler back only to find out that this motor was sized marginally. The rotor had started to demagnitize causing the controller to get hot and shut down. So now with a new 77 amp controller and a Hacker C 5012xl I think I have a problem. 8 T piniom and 95 t main gear. According to FXA's rotor speed calc. the new rotor speed is 2950 no load about 1100 rpms to high and about 660 faster than the builders setup. (not me this is my first and boy has it been expensive) My question is can I adjust the th curve to only be at 66% at full to keep the speed down or will this cause damage to the motor because it is not spinning fast enough.

Thanks
Brian

I am sorry Brian, I misread your first post and skipped right past your question.. You sure can set your throttle curve to run 66% at WOT.
shouldn't hurt a thing. You will get longer run times and lower temps as well. If anything it will make your motor last longer. As long as you are happy with the performance at this setting. Make sure that at the lower throttle settings, that the motor RPM does not bog down under heavy loads/rapid pitch transitions. You might not be getting the full benefit of your power system.
Hope this helps..
Jay

215 chief
11-08-2005, 06:41 PM
Jay
Thanks after all my worrying and checking FX aeromodels calc page I called Hacker. She told me she thought I had a box (some type of gear reduction for a Raptor).She has now sent the correct motor. I guess I am to new to not know enough. One lessoned learned. The new motor should match my gearing.
Brian

zappedalaskan
11-09-2005, 12:25 AM
That is great Brian, I know it is upsetting to spend so much money on new equipment and it still don't work right. Most of us have been there. I am glad you got to the bottom of this. Your E-Raptor should be ballistic now.
It sounds like a nice machine. Have a blast with it and please let us know how it works out.
Take care,
Jay

ozace
11-11-2005, 03:49 AM
I am glad to you got the motor sorted. Its not a good idea to run the esc at patial throttle setting. Amps rise and heat builds up. The most effecient way to run an E motor is 100%, any thing less results in heat and amps.
Kontronik esc's are know to be the best at part throttle use (they auto adjust setting) But even then 85%minimum to keep heat in check.