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Old 05-14-2009, 06:17 PM
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Airflow
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Originally Posted by TeamTekin View Post
Notchy or 'cog torque' is not neccessarily just from a strong magnet or a good thing in a motor design. It is simply the attraction of the magnet to the stack teeth when the motor is not being powered. That same 'drag' is present when the motor is running which is not a good thing overall.

Slotless motors have almost no cog torque, but can have very strong magnets. So you cannot really judge a motor by how hard it is to turn the shaft with your fingers. Some people go to great lengths in the designs to reduce the cog torque.

Our slotted 1/10 and 1/8 motors have very little cog torque and very strong magnets. Smooth low end and plenty of power.

Tekin Prez
I switched to BL systems because of cog-torque from brushed motors. My
EX motors (bonded rotor) is what I was looking for. It runs so smooth,
relieving stress from drivetrain off power (coasting). Problem is it lacks
power so I bought a Vector X11 and was overly dissapointed. It has so
much drag off power that it made the car very unnatural to drive. I think
that motor is for racing. I cant complain about the power, it's fast but it
doesnt seem right. My LRP Sphere broke and had it exchanged for a new
Novak XBR system, I changed the EX Motor's stock rotor to a sintered
rotor from a Velocity Light motor. 40% improvement in power, efficiency
and braking, there is some low cog-torque but bearable.

If you say you have a powerful motor with low cog-torque, I would
most likely buy one to upgrade some of my aging but still smooth
Novak EX motors. Problem is Tekin products are not carried by our
LHS in the Philippines. Tekin's distributor here closed down some 4 or
5 years ago. Based from reviews and recommendations, Tekin products
are at the fore-front of brushless techs, so I would like to see and buy
your products IF it's available locally.
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