I need the opinion of those who know more than me,,,, i know very little of  e motors ,i admit it.  I have a De Havilland Twin Otter which i built several years ago from plan of MAN. the designer used 2 e motors kyosho 480 with a gear of 2.5\1 using a 10x6 prop. i placed 2 engines 0.10 glow. i never tested this plan. now i would like to change to e motor but i dont have any idia what to put , hobby king has a long list of motors esc ,,,can somebody help me with the right advice?????  thanks

Edited by apaloosa - 07/Sep/2010 at 8:03am

We just came across this French  site.

http://www.bungymania.com/bmdb.php

You will need to click on the "Union Jack" to convert into english language.  The charts are very accurate and the readings are the same as the ones we have measured on prop/engine/LiPo combination's we are using .  Let us know what you think.

T


Edited by BigTradioman - 10/Jan/2011 at 3:50am

ahaa you want somebody else to do the job for you? take the specs of the motor you want and search on the site for equivalents, that's how it works for everyone.

There is only 1 thing wrong with your calculations on watts per pound

Most of the time you cant trust the manufactures ratings on wattage. They will measure the wattage by over propping the motor, causing it to draw max current and increase the wattage measurement to make it look better than it is.

I do it another way. I will measure the current, wattage and thrust of a motor, then match it to my planes.  I figure out what will work the best for the battery, ESC and motor so that I dont over stress any of the above 3. Change props untill I get a maximum thrust with safe readings for everything else.

My rule of thumb is 1.5 lbs of thrust for 1 pound of plane. It gives me a reserve power to get out of trouble if needed.

Just my $.02 worth

Larry

I was shocked to find that out too

If you can't trust someone that is trying to sell you something who can you trust

I guess the old saying "Buyer beware" does have some bite to it.

larry