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sleebus.jones
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Join Date: Dec 2005
Location: Houston, TX
02.20.2009, 10:50 AM

Quote:
Originally Posted by SpEEdyBL View Post
My previous posts I know are 100% correct, because I have the formulas AND actual data to back it up.
Ok, then how do you explain Castle's stance on torque here:

Quote:
Originally Posted by Castle Creations
A high power capable brushless motor in electrical engineering and physics terms, has unlimited torque. We live in “the real world” so technically for us that’s not totally true, but – a brushed motor has a torque level that due to its design has an upper limit, regardless of how much power is being applied to it. That limit is low enough that you can see it clearly on an average track On the other hand, a high power brushless motor’s limit to torque in an RC vehicle is not within the bounds of the motor itself so much, but rather falls on the ability of the battery to deliver current to it. We generally don’t describe these motors in terms of “one has more torque than the other”, but rather “the 7700Kv motor is faster and draws more current than a 5700Kv motor in the same vehicle”. It draws more current, because it’s making the car go faster and doing more work than the 5700 motor is. As long as the batteries used are very good at supplying current without an excess of voltage depression (low internal resistance is good) both motors will appear to have the same torque, even though one is much faster than the other. Battery technology is constantly improving, and the first thing you’ll notice when you use a very good battery pack (or perhaps trying a Lipo pack for the first time) with these systems is a more “punchy” feel when you accelerate. The faster you set up the car to go at full throttle, the more reliant you are on good batteries to flow that current into the motor and maintain acceleration performance. So think of torque as a function of battery capability only.
   
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