TP Motors CM series vs non-CM

[jingalls007]

Is there any danger in using the TP competition motors in non competition applications as long as we?re not maxing out the voltage?

[Peter A]

From my understanding, CM motors are suitable for SAW and not really for oval raacing.

[jingalls007]

From my understanding, CM motors are suitable for SAW and not really for oval raacing.

I wonder why.

If we used them at lower voltage than their recommended max wouldnt they essentially be a non-CM motor capable of CM specs? Is there some inefficiency at lower rpms on the CM motors?

[BlakeT]

I have ran a few with the cm motors for sport running and they are just fine. I think that’s more of a disclaimer for them to be used only for saw at the rated voltages. I am building another boat with a cm motor now.

[tbonemcniel]

I've been wondering the same. I even asked TP directly about it, but their answer was kind of vauge. What could the CM motors have that the regular motors don't? Better or more denser windings? That can only improve efficiency. Higher quality/stronger magnets? That can only improve efficiency. Tighter tolerance bearings? Again, should be more efficient. I would think that at the same load/amp draw and kv, that the CM motors would be more efficient and run slightly cooler.

[jingalls007]

I've been wondering the same. I even asked TP directly about it, but their answer was kind of vauge. What could the CM motors have that the regular motors don't? Better or more denser windings? That can only improve efficiency. Higher quality/stronger magnets? That can only improve efficiency. Tighter tolerance bearings? Again, should be more efficient. I would think that at the same load/amp draw and kv, that the CM motors would be more efficient and run slightly cooler.

Thats where Im at too. A better motor w/no warranty is fine by me.

If the CM motors are meant to operate at higher rpms, is there a consequence to operating at lower rpms.

[RaceMechaniX]

The CM motors have a thicker sleeved rotor which reduces the flux linkage in the motor. So basically sacrificing a bit of the magnetic performance for high speed durability. If you are operating the within the normal bounds of the speed range you would be better off using the standard motor. If you plan on doing speed runs where overspeeds and hard crashes are expected you would be better off with the CM rotors.

[Steven Vaccaro]

The CM motors have a thicker sleeved rotor which reduces the flux linkage in the motor. So basically sacrificing a bit of the magnetic performance for high speed durability. If you are operating the within the normal bounds of the speed range you would be better off using the standard motor. If you plan on doing speed runs where overspeeds and hard crashes are expected you would be better off with the CM rotors.

Thanks for a better explanation than TP could give!!!!

[Peter A]

The CM motors have a thicker sleeved rotor which reduces the flux linkage in the motor. So basically sacrificing a bit of the magnetic performance for high speed durability. If you are operating the within the normal bounds of the speed range you would be better off using the standard motor. If you plan on doing speed runs where overspeeds and hard crashes are expected you would be better off with the CM rotors.

So is it that the CM motor windings are the same as standard and it is just the rotor design that makes them different?

[RaceMechaniX]

As far as I know yes. TP offers the CM with more aggressive KV ratings or conversely allowing more voltage for the same kv.

[Peter A]

So just out of interest, could you put a standard rotor into a CM case, and would there be any advantage to it?
The 4070 weight differences between the standard 550g, CM 640g and SCM 750g, is this the winding, i.e. the amount of wire? I note that the SCM is 2 pole.

[RaceMechaniX]

No advantage. The winding is the same for the standard and CM. The additional mass in the CM is due to the metallic sleeve over the composite wound sleeve. The SCM is a 2-pole so the winding is different. The SCM rotor and stator are not interchangeable with the other two.

[jingalls007]

The CM motors have a thicker sleeved rotor which reduces the flux linkage in the motor. So basically sacrificing a bit of the magnetic performance for high speed durability. If you are operating the within the normal bounds of the speed range you would be better off using the standard motor. If you plan on doing speed runs where overspeeds and hard crashes are expected you would be better off with the CM rotors.

What would we do without you, Tyler…