Turn to Kv conversion 540 2 pole motors / several brands
 

Novak
http://www.teamnovak.com/products/br...spec_chart.htm

Speed Passion
http://www.speedpassion.net/uploadfi...eb25th2010.pdf

Reedy Sonic
http://www.teamassociated.com/pdf/ca...ec%20Chart.pdf

Viper VST Motors
http://www.viper-rc.com/vst_combo.html

DualSky Z5 Competition Brushless Motor
http://www.dualsky.com/downloads/Z5_...ions_EN_CN.pdf

HOBBYWING XERUN V10 Competition Brushless Motor
http://www.hobbywing.com/product_show.asp?id=295

LRP VECTOR X20 BL Modified Series
http://www.lrp.cc/fileadmin/lrp_anle...ied-manual.pdf

LRP X20 sTock sP XTec
http://www.lrp.cc/fileadmin/lrp_anle...-manual-fv.pdf

The following information is based on what seems to be the most popular "turn" ratings used in 2wd & 4wd 10th scale buggy & Stadium truck. I could not find an on line conversion "chart" produced by the manufacturers for the following list of motors, so I either looked up the motors individually on the manufacturer's web site, or called, and emailed them directly requesting their information. Each of the following manufacturers have more motors available than I have listed. The kv ratings on this post (#1) has been acquired directly from the manufacturers.

Team Orion Vortex VST2 Pro 540 Modified 2P
http://www.teamorion.com/electric-mo...tion-en-2.html
5.5T = 7770kV
6.5T = 6750kv
7.5T = 6200kV
8.5T = 5400kV
9.5T = 4940kV
10.5T = 4570kV
17.5T = 2600kV

Team Trinity D 3.5 motors
Modified
http://www.trinityrc.net/shop/index....ry&path=72_126
Spec
http://www.trinityrc.net/shop/index....ry&path=72_122
5.5t = 9000Kv
6.5t = 6910Kv
7.5t = 6850Kv
8.5t = 6300Kv
9.5t = 6000Kv
17.5t = 2600kV (ROAR spec version) Product Code: TEP1082

Tekin Redline Gen2 (called Tekin to get this info)
http://www.teamtekin.com/redline_gen2.html
5.5t = 7700kv
6.5t = 6700kv
7.5t = 6100kv
8.5t = 5300kv
9.5t = 4900kv
10.5t = 4500kv
13.5t = 3500kv
17.5t = 2500kv

SKYRC ARES PRO MOTOR
http://www.skyrc.com/index.php?route...product_id=190
5.0 = 7050kv
5.5 = 6450kv
6.5 = 5350kv
7.5 = 4700kv
8.5 = 4100kv
9.5 = 3700kv
10.5 = 3450 (modified)
10.5 = 3600 (spec)
11.5 = 3200kv
13.5 = 3050kv
17.5 = 2200kv

Turnigy TrackStar (now ROAR approved)
http://www.hobbyking.com/hobbyking/s...rackstar+motor
4.5t = 7330kv
5.5t = 6075kv
6.5t = 5485kv
7.5t = 5135kv
8.5t = 4620kv
9.5t = 4120kv
10.5t = 3730kv
13.5t = 3040kv
17.5t = 2270kv

Hacker
http://www.hacker-motor-shop.com/e-v...&c=5502&p=5502
4.5t = 7980kv
5.5t = 6500kv
6.5t = 5500kv
7.5t = 5200kv
8.5t = 4700kv
9.5t = 4150kv
10.5t = 3630kv
13.5t = 3150kv
17.5t = 2150kv

Just a few variables to consider with any motor's kv rating

This thread was not created to debate what a true final kv number on any motor, in any given situation might be. Nor was it created to compare brands against each other. I simply created this thread to have a collection of manufacturer's information in one easy place for people who are curious about their claimed kv ratings.

Anyone seeking kv information should keep in mind that there is an infinite list of variables that directly effects kv number claims. To the best of my knowledge (which you should NOT be impressed by), most companies produce their kv ratings by bench testing the motor with no load. "No load" meaning nothing creating any kind of resistance on the motor's output shaft. I only assume 8.4 volts (4.2v per cell max charge on a 2s LiPo battery) of DC power is being supplied to these 540 sized 2 pole sensored motors during testing. You could always contact the manufacturer's customer service to inquire about their specific methods for producing a claimed kv rating.

It is important to know that there is no standard in the RC industry for testing brushless rotors and stators. There are numerous testers on the market, including the Trinity, MMS and others, that all provide different information. The information can vary greatly. For example, one company's meter may read 1500 for a rotor, where another meter may read it as 1400. The same goes for stator readings. For example, a 19.5ohm reading on one brand of meter, may be the same as a 20.2ohm reading on a different tester.

A few other things to consider. Once the motor is installed in your R/C vehicle, and the gear mesh is set, the motor now has a load of resistance to work against. The total weight of your vehicle, final drive gear ratio, slipper clutch adjustment, diff oil consistency, total rotating mass, bearings and seals breaking in, esc settings, end bell timing, and voltage descending as your battery discharges will all have an effect on what the actual total kv that your motor is producing. I'm sure someone that is much more educated on this topic could bring up many more variables than the few listed here.

In some situations, having a kv rating is very useful. For example, in some esc's, you have the option to manually select the rpm in which you want timing advance to begin, and end. In order to get some kind of idea of what your motor's rpm's might be, you multiply volts by the kv number. With a perfect max charge on a LiPo battery, you should have 4.2 volts per cell. Here's a hypothetical figure for example. Remember, this is a max charge voltage number. The rpm will be lower as the battery discharges.

on a 2s max charge
8.4v x 5700kv = 47,880 rpm

Or if you prefer the claimed voltage on a 2s label, you would use this figure.
7.4v x 5700kv = 42,180rpm

If you have your voltage cut off set at 3.2v per cell, you might have an rpm figure like this at the point of cut off with the same battery and motor.
6.4v x 5700 = 36,480rpm

Like I mentioned before, variables could be discussed to no end. At minimum, knowing the claimed kv rating of your particular motor will at least give you a base line / starting point of information for your set up. Then you can tune your particular set up from there. Hope you find the information on this thread helpful. HAPPY RACING :):tire::)

I have not been able to acquire kv ratings for the following brands yet.

SMC Motors
SMC suggests to purchase your own "motor testing equipment", or put a note in the comment section requesting kv information when ordering a motor from them and they will test your individual motor and send the kv rating for that specific motor.
http://www.smc-racing.net/index.php?...y&path=112_102

fantom
http://www.fantomracing.com/products...ODIFIED+Motors

ORCA
http://www.orcarc.com/en/products.asp

Thunder Power
http://www.thunderpowerrc.com/Produc...ushless-Motors

Reedy

Sonic Series

Thanks ! Just added it to the 1st post. I'm planning on adding more manufacturer's to the list as I find time.

KV rating is like the C rating of a battery. Way to many variables to compare ratings from different manufacturers.

Very true about too many variables, but it seems that going by a "turn" rating alone leaves even more variables to consider than using "kv" ratings. At least a kv rating will give you an idea of what rpm's the motor is turning.

For example. 3800kv x 7.4v = 28,000 rpm

Another way this can be very useful information is for someone who is tuning a Tekin ESC with their Tekin HotWire. The program asks for rpm information to be entered. This greatly optimizes performance, and efficiency. I'm sure other brands of esc's may use data like this also.

+1 for this thread. Nice info here.

Thanks, I noticed a lot of other drivers was just as curious about turn to kv conversions as I am. Figured it might help to put it all in one place. I'll be adding more manufacturers for 540 size motors in the near future.

Try to find out what smc's turn to kv conversion is

Do you know how theres are tested? if not, its not really a valid number like a C rating on a lipo. Changing the voltage on a motor affects the KV, its not a linear relationship. Static timing also plays a huge roll in the KV, take a revtech with max timing and you'll thing its faster then a mod motor.

SMC motors will most likely have the same kv rating as the dualsky z5 motors. If you open up your smc motor and look at the stator on the endbell end it is clearly says dualsky.

When I get a chance I will list the skyrc ares pro motors kv and turn rating

http://www.skyrc.com/index.php?route...product_id=190

http://img.photobucket.com/albums/v3...069D398BC7.png

Hobbywing V10 line of motors:

http://www.falconsekido.com/products/xerun-v10-motor

http://img.photobucket.com/albums/v3...72A4730A_1.png

That's true if and only if the tests to measure the KV rating were done at the same voltage, static timing, and timing ramp conditions that you are using. Not only do you have no way (in general) of knowing what those settings are, it is highly unlikely that every manufacturer uses the same settings to measure their motors.

Your statement is true. This thread was not produced to debate that fact. I only created this thread with the intention to provide a collection of manufacturer's information for people who like to know what the kv rating of a certain motor is.

Personally, I find "turn" ratings entirely too vague. I prefer the information of kv ratings.

As I mentioned before, the esc's I use ask for rpm information to be entered into the program. This requires voltage multiplied by kv. Which is what is provided on this thread. It's impossible to figure rpm according to a "turn" rating, and the esc I use has no place to enter a "turn" rating.

If you want to debate with someone about the methods of producing correct information, contact the manufacturers. The information you disagree with belongs to them...