Verified information about Puma winding number <-->RPM relation needed

Hey guys,

I recently finished my ebike. It's a Giant Revive with 20" wheels, a 16S LiFePo battery (51V) and a Puma (with 225RPM/36V).

This setup is a bit too fast for me, I want the freewheeling RPMs of the motor to max out <25km/h. Right now, the freewheeling speed goes up to 34km/h. A Motor with 175RPM/36V would be ideal for me. This version is listed at my vendor:
http://www.ebike-solutions.com/de/shop/motoren/motoren-bis-250w/puma-vorderradmotor-250w.html

Having wound RC motors myself in the past, I thought it would be a nice challenge to do this, and just change a newly wound stator against the old one, instead of changing the motor. Here is a tutorial in a german forum:
https://www.pedelecforum.de/forum/index.php?threads/puma-mac-motor-neuwickeln-tutorial.28738/

What I am looking for now is verified information, which tells me which freewheeling RPM I can expect with a specific winding number at a specific voltage. Wherever I look, and there are not many places, I find conflicting information.
The guy from the forum link above had 11 windings, and from the information he gave me personally achieved around ~260RPM/36V.

This conflicts with the information I find here:
https://web.archive.org/web/20160406145800/http://em3ev.com/store/index.php?route=product/product&path=40&product_id=52

Turns; RPM/36V loaded
12; 200
10; 255
8; 320
6; 410

According to this table, 11 turns should get me around 230 RPM.

I found an image of my motor, and I count something between 15 and 17 windings (maybe double windings?).

This again does not correspond with the two pieces of information mentioned before.

So, what is it now? How can I know without trying different winding numbers how many windings I need to get 175RPM/36V?
I want to use the attached winding scheme with Y termination.

Thanks a lot.

Regards,

Julian

You want to tear into a new(and expensive, no doubt) motor and start unwinding copper? I think you will find it to be more of a chore than a fun project. Especially when could just reduce the Voltage to 36 V and be at the speed you want w/ little loss of efficiency.

Hi, I do not plan to tear my working stator apart as of yet. I asked the local Puma distributor if they could order me a "naked" stator a few days ago, but the answer is still pending. Changing the battery is out of the question, as it is a custom built of 64 single A123 cells.