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WrknItUp
09-14-2010, 05:25 PM
Okay ive seen alot of people using outrunner motors compared to an inrunner. First thing i noticed is the whole motor spins correct? Also do you watercool an outrunner like an inrunner or do they even have water cooling capabilities? New to outrunner motors wondering what all there has to be done to convert.

scoota
09-14-2010, 08:04 PM
Yes the outer can spins , you can use a water cooled mount to help cool them , the outrunners have a lot more torque/ power than a inrunner , the down side is the bigger outrunners dont have a high KV range..

WrknItUp
09-14-2010, 09:07 PM
Yes the outer can spins , you can use a water cooled mount to help cool them , the outrunners have a lot more torque/ power than a inrunner , the down side is the bigger outrunners dont have a high KV range..

what do you mean they dont have a higher kv range? your saying the bigger the can is not always more power or they cant take the high rpms? so they do have watercooling options? do they have to be watercooled?

Fluid
09-14-2010, 09:21 PM
The outrunners simply do not have the power of a top-end inrunner. They cannot spin fast enough nor can they handle the amp draw. If winning races is your goal, then in most cases the outrunner is not the best choice. The exceptions are classes with motor restrictions.

Because of their construction, outrunners cannot spin as high as the faster inrunners. Their hollow rotors will distort at high rpm, unlike the solid, smaller diameter rotors on inrunners. Few larger outrunners have a Kv above 2000 - while a Kv over 2000 rpm is needed for most racers on 4S for example. A larger prop spinning slower can help bridge the gap...but large props can lead to lots of prop walk and poor turning.

OTOH I really like outrunners for sport motors. They spin a large prop and because they do not handle high amps you will get more run time out of them. Speeds are not as high, but still high enough to be exciting. I am glad we have outrunners!




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WrknItUp
09-14-2010, 09:29 PM
okay that helps. Im not looking to race yet, but i am looking to go fast. So for hard turned rpms and shocking speed stick to inrunners for massive torque and some speed outrunners. Okay still how do you cool and out runner compared to an inrunner? Im going to stick with the inrunner for now i guess.

scoota
09-14-2010, 09:31 PM
Have a look at my thread ( 62mph -BJ) that has a 4020-1390kv outrunner motor on 6s in it with a water cooled mount & im gpsing speeds of 55-62 mph with that set up